HKSAR v. Khaw Kim Sun
Read the full judgment text of CACC 309/2018 on BabelCite. This Court of Appeal judgment was delivered on 7 June 2022 before Poon CJHC, Macrae VP and Zervos JA.
Criminal law – murder – two counts – carbon monoxide poisoning – circumstantial evidence – burden and standard of proof – summing-up – expert evidence – directing jury – leave to appeal. The applicant, an Associate Professor in Anaesthesia and Intensive Care at the Chinese University of Hong Kong, was convicted of two counts of murder after his wife and 16-year-old daughter were found dead from carbon monoxide poisoning in a yellow Mini Cooper on 22 May 2015. The prosecution alleged the applicant filled a yoga ball with carbon monoxide under the guise of sham medical research, brought it home, and placed it in the car to kill his wife. The applicant denied placing the yoga ball in the car and relied on his out-of-court statements and expert evidence, contending that his research was genuine, that he intended to use the CO to kill rats at home, and that the deaths were possibly an unexplained accident or caused by someone else (possibly his daughter Lily). The court considered 20 grounds of appeal under four headings. Held, dismissing the application for leave to appeal: (1) the trial judge's directions on burden and standard of proof were correct and followed the Specimen Directions in Jury Trials; (2) the summing-up was comprehensive and balanced, fairly presenting the defence case including the timeline defence, the genuineness of the research, the missing stopper issue, and the possibility of an unexplained accident; (3) the trial judge did not improperly remove the issue of unexplained accident from the jury, but properly directed the jury on the main issue of who placed the yoga ball in the car and why; (4) the trial judge's directions on expert evidence were thorough and balanced, fairly summarising the conflicting evidence on both the research protocol and the diffusion rate of carbon monoxide. The court found the applicant had a thoroughly fair trial, that there was cogent and compelling evidence to justify his convictions, and that none of the 20 grounds disclosed any arguable error. Application for leave to appeal refused; appeal dismissed.
Legal issues: Application for leave to appeal against conviction for two counts of murder
Outcome: Application for leave to appeal against conviction refused; appeal dismissed
Cited by 5 cases · Cites 6 cases
|
CACC 309 /2018 [2022] HKCA 802 IN THE HIGH COURT OF THE HONG KONG SPECIAL ADMINISTRATIVE REGION COURT OF APPEAL CRIMINAL APPEAL NO 309 OF 2018 (ON APPEAL FROM HCCC NO 374 OF 2017) ________________________
________________________
____________________ J U D G M E N T ____________________ The Court: Contents The relationship between the applicant and his wife The character of the applicant The applicant’s research on rabbits The diffusion rate of carbon monoxide An overview of the grounds of appeal
The form and content of the grounds of appeal The burden and standard of proof The applicant’s right of silence The directions on the expert evidence 1.On 19 September 2018, the applicant was unanimously convicted after trial before Barnes J (“the Judge”) and a jury of nine of two counts of murder, contrary to common law. He was sentenced to life imprisonment on each count and now seeks leave to appeal against his convictions. Having reserved our decision at the hearing of the appeal, this is the unanimous judgment of the Court. 2.On 22 May 2015, Ms Tong Yuk Ling (PW1) (“Ms Tong”), a nurse, was on her way home when she noticed that a yellow Mini Cooper (“the Mini”) had stopped at a bus stop outside Sai O Village in the New Territories. There appeared to be two people asleep inside the car. 3.On arriving home, Ms Tong decided to go out for a run. Whilst on her run, she again saw the Mini and its occupants, but on this occasion she did not stop. On her way home, however, she passed the vehicle again and this time she noticed that the windscreen wipers were operating, even though it was not raining. Ms Tong knocked on the window of the vehicle. There was no response and, accordingly, she made a report to the police. 4.A police sergeant, who happened to be in the area, soon arrived at the scene and smashed one of the windows of the Mini; thereafter, an ambulance arrived. The two occupants, each apparently unconscious, were removed from the vehicle and taken to hospital, where they were both certified dead. The cause of death of both persons was later established to be carbon monoxide poisoning. 5.The two occupants of the car were the applicant’s wife, Madam Wong Siew Fing (“Madam Wong”), and her 16-year-old daughter, Khaw Li Ling (who was known, and referred to at trial, simply as “Lily”). The police initially suspected that the carbon monoxide must have emanated from the Mini, yet after investigation they could find no mechanical defect with the vehicle to account for the tragedy. In the boot of the Mini was a partially deflated yoga ball. It was not apparent at that stage that the yoga ball had been the source of the carbon monoxide. 6.The applicant, who was an Associate Professor in the Department of Anaesthesia and Intensive Care at the Chinese University of Hong Kong, had filled the yoga ball with carbon monoxide and brought it to his family home on the night before the incident. 7.About a year later, on 12 May 2016, the applicant was arrested inside his office at Prince of Wales Hospital by Lam Kam Cheung, Detective Sergeant 16404 (PW15) (“DSgt 16404”) in respect of two offences of murder. Under caution, the applicant replied in Cantonese:
8.On the following day, 13 May 2016, the applicant gave the first of three video recorded interviews under caution, all of which were conducted by two officers, one of whom was DSgt 16404. The applicant was throughout represented by both counsel and an instructing solicitor. No issue as to the voluntariness or admissibility of his out-of-court statements was taken by the applicant at trial. 9.The case for the prosecution was that the applicant had murdered both Madam Wong and Lily by deliberately placing a yoga ball filled with carbon monoxide gas inside the Mini and removing the stopper or plug, thereby causing the gas to escape and fatally poisoning them both. The prosecution suggested the applicant had intended to kill his wife but, tragically, he had also killed his daughter in the process. 10.A subsequent examination of Madam Wong and Lily revealed that the carboxyhaemoglobin detected in their blood was at a level of 50% and 41% respectively with the time of their deaths estimated at between 12:45 and 2:45 pm on 22 May 2015. Carboxyhaemoglobin is a consequence of the ingestion of carbon monoxide into the body and the levels of carboxyhaemoglobin suggested that both Madam Wong and Lily had ingested a substantial quantity. 11.The prosecution alleged that the applicant had ostensibly embarked on some purported medical “research”, which was in fact a sham, in order to obtain a supply of carbon monoxide for the purpose of killing his wife[1]. Their alternative position was that if the jury were to find that this research may initially have been genuinely undertaken and the carbon monoxide thereby obtained for a legitimate purpose, he had subsequently decided to use the gas to kill his wife. It was argued by the prosecution that the applicant’s suggestion that carbon monoxide could be used as an effective means for killing mice or rats was a “silly idea”, which defied critical examination[2]. 12.On 20 May 2015, the applicant was observed by his research fellow, Dr Dick Chow Ho Kiu (PW9) (“Dr Dick Chow”), filling two empty yoga balls, one blue and one grey, with carbon monoxide from the cylinder in the laboratory. The applicant explained to Dr Dick Chow that he had done this so that a friend could check the purity of the carbon monoxide. The applicant subsequently admitted in a video recorded interview that this explanation was untrue. He said that he intended to use the carbon monoxide to kill mice or rats at his home. 13.The applicant accepted that he put the two yoga balls in his Toyota Alphard, which was parked at the Prince of Wales Hospital. He left the car there overnight and went to his girlfriend’s home nearby, where he stayed for the night. He had also installed two carbon monoxide detectors in the vehicle. He did not get back to his vehicle until after work on the following day, which was a Thursday. He noted the detectors were emitting an alarm and found that the blue yoga ball was leaking carbon monoxide. He released the carbon monoxide from the blue yoga ball and then went back to his family home. Having arrived home, he left to play in a tennis match and took the Mini instead. On subsequently returning home, and after the children had gone to bed, he retrieved the grey yoga ball from his Toyota Alphard. He placed it in the exercise room, intending in due course to connect it to a drainpipe in order to kill rodents. Lily came into the exercise room and saw the yoga ball. He told her it was filled with carbon monoxide and she then asked him whether it was to kill rats “or something like that”. 14.It was usual for Madam Wong to pick up the two younger children from school in the afternoon, which was part of her normal routine. On the Friday, Lily did not have to go to school and, accordingly, stayed at home. The applicant accepted that he had told Lily to finish her outstanding homework and not to go out. He said he also asked his wife to ensure that Lily stay at home to finish her homework. However, Lily joined Madam Wong and they went out together in the Mini. 15.The family’s domestic helper, Ms Siti Maesaroh (PW6) (“Siti”), testified that she saw both Madam Wong and Lily leaving the house and getting into the car at “around 2:00 pm”[3]. She had watched them from the upper floor of the house as they got into the car[4]. She said it was raining at the time[5], but not very hard[6]. She did not see either of them carry anything to the car. The car also had two transponder keys: the last updated record for the car key of Madam Wong was at 2:18 pm on 22 May 2015[7]. These facts, when taken together, said the prosecution, indicated that it must have been very shortly after leaving home that Madam Wong stopped the Mini at the bus stop. As will later become apparent, this time frame was variously addressed at trial and this appeal, and has been termed by the applicant in argument before us as the ‘timeline defence’. 16.Ms Tong, who first happened upon the Mini stopped at the bus stop, said that it was 3:35 pm when she first noticed the car on her way home, and that the windscreen wipers were on but that there was no rain. Having arrived home, she changed and went for a run. At about 3:55 pm, she saw that the Mini was still in the same position. On her way home, she again passed the Mini at about 4:15 pm. It was then that she had knocked on the window and, after getting no response, called for help[8]. 17.It was an admitted fact that the location where Madam Wong and Lily were found was about 1.6 kilometres from the house[9] where they both lived with the applicant and two other children of the marriage. The eldest child, Khaw May Ling (PW11) (referred to as “May May” at trial), was away in Malaysia, where she was studying medicine. It was common ground at trial that it would have taken about 15 minutes to drive from the family home to the place where the Mini was found. 18.The prosecution did not have any direct evidence that it was the applicant who had placed the yoga ball inside the boot of the Mini. There was no eye-witness evidence of anyone placing the yoga ball inside the vehicle. Instead, the prosecution case proceeded on the basis that, by a process of elimination, the applicant was the only one who could have placed the yoga ball inside the Mini and removed its stopper or plug. 19.The prosecution further commented that it was highly convenient that the only other person, whom the applicant claimed knew about the yoga ball being filled with carbon monoxide, was Lily, who could not, of course, confirm this assertion. 20.The defence case was the applicant did not put the yoga ball into the Mini. There was no motive for him to kill his wife; moreover, the research he was conducting was not a sham. While the applicant did not give evidence himself, he relied mainly upon what he had said in his three video recorded interviews, and on the evidence of various expert witnesses. 21.The late Mr Gerard McCoy SC, with him Mr Kim McCoy, on behalf of the applicant at trial, argued that there was no clear motive for him to murder his wife or daughter. Money did not provide a sufficient justification, since the bank accounts of his wife and himself were joint accounts, from which he could have removed any money he wanted at any time[10]. Nor was his relationship with another woman a sufficient motive, since his wife had come to terms with his affair and reconciled herself to his infidelity[11]. He added that the applicant would not have put in jeopardy his successful professional career, or the care of his children and home, which were attended to by his wife[12]. 22.Mr McCoy listed a number of factors to show the applicant was not a person likely to have murdered his wife and daughter. He submitted that the number of people (some twelve in all) who would have known about the applicant purchasing carbon monoxide, and the clear paper trail linking the applicant to the gas, both militated against him having planned the murder of his wife[13]. He argued that the applicant was a person of good character, with a high professional and academic standing as a doctor, whose work involved saving lives, not taking them. It was also pointed out that if the applicant had really intended to kill his wife in this way, he ran the obvious risk that he might kill the two children she was due to collect from school as well[14]. 23.Mr McCoy commented that it was some six months after the incident on 22 May 2015, that the police turned their attention to the yoga ball as the source of the carbon monoxide. During that period, the Mini had been stored by the police and was variously examined in order to determine the source of the carbon monoxide that killed Madam Wong and Lily. 24.When the police eventually turned their attention to the yoga ball, it was located in a collapsed state in the boot of the Mini. The stopper or plug of the yoga ball was not apparently found by the exhibits officer Chan Ching Lun, DPC 7021, (PW17) (“the exhibits officer”). Since he had mistakenly numbered some exhibits, Mr McCoy queried whether the exhibits officer had also made a mistake about not finding the stopper. He invited the jury to consider how the items, particularly the yoga ball, were only found in the boot of the Mini after a lapse of some six months, suggesting that things may have been moved around during this period. He asked them to consider whether the yoga ball had been found in a “neatly folded state”[15]. 25.Leading counsel invited the jury to consider other possibilities for the deaths on the evidence[16]:
Whilst accepting that Lily had not committed suicide, Mr McCoy did advance one possible explanation, namely, such was Lily’s phobia of insects that she might have brought the yoga ball out of the house, unaware of the extreme danger of its contents, in order to exterminate insects she may have seen in the Mini, before setting off with her mother to collect her siblings from school[17]. 26.There were two major areas of dispute at trial, both of which heavily depended on the evidence of experts. The first area was the applicant’s research on the effectiveness of using oxygen to rescue live rabbits suffering from carbon monoxide poisoning. The prosecution contended that the research was a sham, in order to provide an excuse for the applicant to obtain a supply of carbon monoxide. The prosecution therefore sought to show that the experiments conducted by the applicant were of no scientific utility or benefit: the defence argued otherwise. 27.The second, which we have briefly alluded to, involved the timeline defence. The argument advanced was that, in order for the carbon monoxide concentration to have been lethal enough to kill, the yoga ball would have had to have been placed in the Mini not long before they left home. If that was the case, then it would rule out the applicant as the person who put the yoga ball inside the car, since he was teaching at the Chinese University at the relevant time. The relationship between the applicant and his wife 28.Before turning to the issues raised by this appeal, it is helpful to say something of the dynamics within the family relationship, since this also was a significant aspect of the trial. Madam Wong was a housewife and it was clear from the evidence that her relationship with her husband had become an unhappy one. A friend of the family testified that the two did not talk to each other, but communicated by messaging. May May said that sometimes she would have to relay messages back and forth between her parents[18]. 29.That Madam Wong knew of her husband’s affair with another woman was confirmed in evidence by Madam Foong Wai Yee (PW7) (“Madam Foong”), a friend of Madam Wong. In late 2013, Madam Wong had been diagnosed with moderate depression and anxiety[19]. However, Madam Foong said she had got over this and had been happier during the first few months of 2015 before her death[20]. There was evidence that Madam Wong had joined an organisation to improve herself (May May described it as a “cult”), and the defence further produced Madam Wong’s diary, in which she had listed all her shortcomings[21]. 30.Dr Victor Cheong Mun Khan (DW2) (“Dr Cheong”) was a family friend and doctor from Malaysia. He considered that Madam Wong had changed in recent years, and that she had begun to spend more money[22]. 31.The applicant accepted that his relationship with his wife was not good. This was particularly so after May May had been diagnosed with a blood disorder. He maintained that he and his wife had discussed divorce, but each felt they could not cope with the four children individually, so they had decided to stay together as parents in order to look after them. He acknowledged that his wife knew about his affair but did not seem to want a divorce[23]. 32.A number of witnesses[24] testified that Lily was clever, energetic and full of life. May May said Lily had been diagnosed with Attention Deficit Hyperactive Disorder (“ADHD”) and dyslexia when she was about 6 or 7 seven years of age. There was one apparent reference in the evidence to the subject of suicide. In an e-mail exchange between May May and the applicant, May May had told him, “I don’t want to drag Lily into this but there are things that even she wouldn’t bother bringing up with you, which is relieving, because I don’t want the same thing to happen to her”[25]. Nevertheless, the Judge remarked that there was no actual evidence that Lily was suicidal[26]. 33.There was, however, evidence that Lily was terrified of rats and insects. Ms Eunice Li Lok Ting (DW3) (“Eunice”), Lily’s school friend, described how Lily would jump up on a chair, or run out of class, if she saw an insect. She also testified that she had seen something of Lily during Easter 2015, and she appeared happy. Dr Cheong said he had seen Lily only five days before her death, and he also described her as happy and full of life. There were Facebook chats produced between Lily and Ms Sarah Niu (PW18) (“Sarah”), another of Lily’s school friends, on the Friday she died, in which Lily had suggested going out with Sarah on the following Monday[27]. 34.The applicant had told the police that he thought Lily wanted to commit suicide, and he did not know whether this was because she felt that he had put too much pressure on her to study, or whether she had possibly had a disagreement with her mother[28]. Against this, the prosecution submitted that if, indeed, it were true that Lily intended to commit suicide, then she must have intended to kill her mother as well[29]. The character of the applicant 35.The applicant was a highly competent professional and the sole financial support for his family of six. He was a professor at the Chinese University and a senior medical officer at the Prince of Wales Hospital. According to May May, he had pushed his children to better themselves. It was her view that he did not understand ADHD, something from which both she and Lily suffered. 36.Professor Leung Tak Yeung (DW5) (“Professor Leung”) explained that whenever high risk cases were referred to the Prince of Wales Hospital, he would ask the applicant to assist him; for example, if there was a particularly complicated pregnancy to deal with. He said the applicant was somewhat avant-garde in his approach to new methods and was well ahead of others in this respect[30]. Dr Cheong said the applicant was a clever man and devoted to his family. He said he was a man well able to control his temper[31]. 37.As we have already noted, the expert evidence in this case principally focused on two issues. The first, in relation to which three expert witnesses were called, namely Professor Kwong Yok Lam (PW21) (“Professor Kwong”), a professor in haematology at the Department of Medicine, University of Hong Kong, Professor Gavin Matthew Joynt (PW22) (“Professor Joynt”), the Chairman of the Department of Anaesthesia and Intensive Care at the Chinese University, and Professor Michael Garnet Irwin (PW23) (“Professor Irwin”), a professor in Anaesthesiology at the Faculty of Medicine, University of Hong Kong, for the prosecution[32]; and Professor Nicholas Allan Buckley (DW1) (“Professor Buckley”), a professor in Clinical Pharmacology at the Medical School, University of Sydney, Australia, and Professor Wang Chi Chiu (DW6) (“Professor Wang”), the Divisional Head of the Department of Obstetrics and Gynaecology at the Chinese University, for the defence, concerned whether or not the experiments done by the applicant on rabbits amounted to genuine research. The second issue, in respect of which the prosecution called Dr Wong Koon Hung (PW20) (“Dr Wong”), a Forensic Government Chemist, and the defence, Professor Li Chi Kwong (DW4) (“Professor Li”), an engineer at the Hong Kong Polytechnic University, concerned the diffusion rate of carbon monoxide inside the Mini; which issue was relevant to the timeline defence. 38.The prosecution experts essentially maintained that they did not see any clinical benefits from studying the elimination half-life[33] of carbon monoxide in a rabbit during oxygen therapy. They were also critical of the methodology used by the applicant in his experimentation, pointing out that people who suffered from carbon monoxide poisoning would have inhaled the gas and not had it injected into their bloodstream. Accordingly, they queried if there was any point in a study in which blood was extracted, infused with carbon monoxide and then directly reinjected back into the subject[34]. 39.The prosecution experts stated that when treating a patient who had inhaled carbon monoxide, the standard procedure was to use 100% oxygen, with or without pressure, in order to save the patient’s life. There would be no question of using 60% or 80% oxygen, as the applicant had apparently used in his experiments on rabbits[35]. 40.On the other hand, the defence experts stated that there was some utility in supplying a lesser percentage of oxygen because of the harm caused in giving a patient 100% pure oxygen. The defence case was that the carbon monoxide was being used to produce a state of hypoxia, in order to test the concentration of oxygen in the blood[36]. The applicant’s curriculum vitae indicated that he was doing research into ‘supplementary oxygen’: his experiments on rabbits could be considered consistent with such research. Professor Buckley explained that there was some clinical relevance in drawing blood, infusing it with carbon monoxide and then reinjecting it into an animal; it might provide some interesting insight as to how carboxyhaemoglobin was dealt with by the body[37]. When asked, in cross-examination, whether the injection of carbon monoxide into the blood of an animal was of any utility, Professor Buckley responded that “the use is not immediate, but there might be an insight as a result”[38]. He believed that the study could be of some academic utility[39]. 41.Professor Wang was a colleague of the applicant and co-author of various academic papers with him. He stated he had no track record in carbon monoxide research, and that he was providing expert opinion specifically on the study of protocols and related documents[40]. He testified that the applicant’s study protocol was an animal study, not a clinical study. He said it was relatively short and simple but was still a developing one, and from a clinical point of view the protocol was very good[41]. In cross-examination, Professor Wang maintained that the method used had direct clinical use. He was of the view that the applicant was nonetheless trying to establish an “acute carbon monoxide poisoning model”[42]. However, his evidence appeared to be rather undermined when he suggested that blood infused with carbon monoxide had been reinjected into the rabbits. He accepted that the method of reinjecting saturated carbon monoxide blood had no direct physical relevance. He also accepted that the normal method of acute carbon monoxide poisoning was by breathing[43]. It is to be noted that Professor Wang’s expertise was not in carbon monoxide research. He said he thought he could determine reinjection by the oximeter readings which demonstrated that the applicant had injected saturated carbon monoxide blood back into the rabbit.[44] He later stated in cross-examination that he believed reinjection took place because of two facts, namely he had repeatedly asked the applicant and the changes shown on the oximeter readings. This was contrary to the testimony of those present at the experiments, as well as the documentary evidence. The applicant’s research on rabbits 42.The applicant had proposed a research project which involved the infusion of carbon monoxide into rabbits. As noted earlier, it was part of the prosecution case that this research was a sham in order to prevent questions being asked about the applicant’s procurement of carbon monoxide. Further, the prosecution submitted that this research was outside the speciality of the applicant and his known field of research. 43.In about December 2014, Professor Qin Ling (PW8) (“Professor Qin”), a professor at the Chinese University, said he remembered playing tennis with the applicant, during which the applicant mentioning his desire to use animals for research. Therefore, Professor Qin asked his assistant, Dr Dick Chow, to liaise with the applicant about the experiments[45]. Thereafter, Dr Dick Chow was the one who forwarded the relevant forms to the applicant for him to submit to the Ethics Committee, and who helped the applicant order carbon monoxide. 44.Professor Joynt was the head of the applicant’s department. He was the applicant’s supervisor and it was he to whom the applicant, in the normal course, would have had to forward his research. He said that the first time he had seen these documents was when the police had shown them to him. This was not challenged by the defence. The applicant admitted in his video recorded interview that the relevant proposal forms were never actually submitted to the department[46]. 45.Professor Joynt explained how he had looked at the applicant’s curriculum vitae and saw no direct link between carbon monoxide poisoning and any of the applicant’s particular interests[47]. He said it was normally his job, if a proposal came to him, to vet it. Had he seen this proposal, he would have sent it back and there was no way he would have passed this on to the Ethics Committee, since it was too crude and rudimentary[48]. He thought the applicant’s animal research protocol was not well thought through. 46.Professor Buckley was of a similar view, saying in cross-examination, that if he had been on the Ethics Committee, he would have sent it back too, as it was still in draft form and there were question marks in respect of it[49]. 47.Professor Buckley, when asked about the protocol in examination-in-chief, testified[50]:
48.In cross-examination, however, Professor Buckley elaborated as to why he would have sent the protocol back. He pointedly expressed his view in the following exchange[51]:
49.Ms Tam Tsui Ping (PW23) (“Ms Tam”), the applicant’s laboratory assistant, described two experiments, one on 13 May and the other on 20 May 2015, where the applicant, it would appear rather unsuccessfully, sought to infuse rabbit blood with carbon monoxide.[52] This was also the evidence of Dr Dick Chow. In neither experiment was it apparent that carbon monoxide blood was in fact infused back into the rabbit[53]. The prosecution said, of the experiment on 13 May, it “wasn’t much of an experiment at all”[54]. 50.Whilst there was evidence of the applicant using carbon monoxide for his research in these two experiments, there was no evidence of him studying any patients who had been poisoned by carbon monoxide; it was apparent he had done research on oxygen therapy, or what is called ‘supplemental oxygen therapy’, but this was all in relation to saving pregnant women who were giving birth[55]. 51.After the second experiment, the applicant was observed filling up two apparently empty yoga balls, one blue, and one grey, with carbon monoxide from the cylinder in the laboratory. The applicant explained to Dr Dick Chow that he was filling up the yoga balls with carbon monoxide in order to take them to a friend to analyse their “purity”, but the applicant subsequently admitted in his video recorded interview that he had “made up a story” so that he would not challenge him for removing laboratory materials[56]. 52.The applicant admitted that he was the one who filled the two yoga balls with carbon monoxide; and that this followed the failed experiment of 20 May 2015. 53.The applicant said he had tried getting rid of the rats at home using sticky pads, but this was unsuccessful. He had also tried using cages but, again, to no avail. He considered using poison but, since he had pets at home, he did not think it was a good idea. However, after having done the experiment using carbon monoxide, the idea came to him that he could use gas to kill rats[57]. 54.He maintained that it was safe to use a yoga ball to contain the carbon monoxide since the material was tough. His plan was to fill the yoga ball with carbon monoxide and then connect a tube to the ball and pump carbon monoxide from the yoga ball into the drainpipe from which the rats were emerging. 55.He said that after he had filled the two yoga balls with carbon monoxide, he left them in his car, a Toyota Alphard, which was parked at the Prince of Wales Hospital, and then stayed the night at his girlfriend’s home, which was near the hospital. He had also installed two carbon monoxide detectors in his car. 56.The applicant did not get back to his car until after work on the Thursday (19 May). He then noted the carbon monoxide monitor was sending out an alarm and he discovered that one of the yoga balls was leaking. Consequently, he emptied the carbon monoxide from this particular yoga ball, leaving the other one still with its carbon monoxide contents in the car. The prosecution made the point that his ability to do this safely indicated the applicant knew what he was doing in handling a poisonous gas[58]. 57.To put these assertions in their proper context, the prosecution described the carrying of yoga balls filled with carbon monoxide as “crazy”[59] and said that a yoga ball full of carbon monoxide let loose in a court room would likely have killed everyone inside in 5 to 10 minutes[60]; whereas the defence countered that “in some ways only a person that brilliant can be that stupid to bring it home, because none of us would have done that”. Further, someone who was that clever would not have left so many “obvious signposts that it was him”[61]. 58.Having picked up his Toyota Alphard, the applicant then drove home, where he left his car and went off to play a tennis tournament driving the Mini[62]. When he returned home from the tennis tournament, he said he joined his children in the exercise area. Having sent the two younger children to bed, he saw that Lily was still up exercising on the treadmill. When he thought the treadmill had stopped and that Lily had gone to bed, he went out to the Toyota Alphard and brought the yoga ball filled with carbon monoxide inside the house. 59.It so happened that Lily then returned and saw him place the yoga ball in the corner of the exercise area[63]. He told Lily that the yoga ball contained poisonous gas, with which he intended to kill rats over the weekend. She had replied, “Oh, is it very bad, very poisonous? Would it kill the rats or something like that?”. His thinking was even if there was leakage it would only constitute a small volume of the entire house, so it would not be dangerous[64]. 60.The applicant said that, on 22 May, he got up between 9:30 and 10:00 am. His wife was still asleep. He made himself some coffee and wandered around the garden, before doing some work in the study. When he later came down, he saw his wife and Lily both eating. He then left for work at about 12:30 to 1:00 pm[65]. He said he did not notice if the yoga ball was still inside the house on 22 May after he got up, and he had no idea how the yoga ball had found its way into the Mini. Since Siti did not see the applicant leave the house, the prosecution submitted it was a fair inference that the yoga ball had been placed in the Mini at about 12:00 pm without its plug. 61.The applicant admitted he did not tell the police investigator, who came to the house as part of the investigation on 24 May, that his wife and daughter were killed by the carbon monoxide from the yoga ball, which he himself had filled with the gas; he admitted being a coward in letting people think the carbon monoxide came from the engine of the car[66]. He also said he did not tell the police because he did not want to get people such as Dr Dick Chow into trouble. Nor did not want his children to be without a parent should he be taken away. 62.The prosecution submitted the applicant knew full well the danger posed by the carbon monoxide in the yoga ball, and yet he introduced it into his family home without telling anyone, as part of the plan to kill his wife. Mr Andrew Bruce SC, with him Ms Christal Chan, for the prosecution, commented rather graphically, “he said that he knew that the kids sat on the yoga balls. Well, that’d be good wouldn’t it? Sitting on a yoga ball full of carbon monoxide. Boom”[67]. This conduct was said to be in contrast to the applicant’s caution in ensuring that there were two gas monitors in his own car to warn if carbon monoxide was leaking from the yoga ball[68]. 63.The defence answer to this point was that the applicant was the sort of person who was “nerd-like” and viewed things with “tunnel vision”; or, as the Judge characterised the argument, “he does not think the way how we think. He just did not even consider that it could be dangerous to do such a thing. It is a matter for you”[69]. 64.Siti testified that she had never seen any rats or evidence of rat droppings[70]. On the other hand, May May testified that many rats emerged at night, but they quickly disappeared. However, as the Judge pointed out, May May had been pursuing her studies in Malaysia since the beginning of the year, so would not have been familiar with the position prior to the incident in May 2015[71]. Photographs of the drain[72] at the family home were produced and shown to the jury. The applicant also produced a sketch of the house, with the drains shown, and used it to describe how he was planning to use the yoga ball, connected to a tube, to pump carbon monoxide into the drains. 65.It is also relevant to note here that, according to the evidence of the exhibits officer, the plug or stopper of the yoga ball was not found when he searched the car. His reliability, however, was challenged on this issue and it became clear that he had evidently mixed up the exhibit numbers of the two car keys[73]. On this issue the Judge directed the jury, “… if you are sure that the exhibits officer was telling you the truth that there was no plug, then whoever had put the yoga ball in there had removed the plug totally”[74]. 66.Dr Wong, for the prosecution, tested the Mini to see, amongst other things, whether there was any leakage of gas, what the dissipation rate of gas from the yoga ball was and how much concentration there was at different time intervals[75]. His methodology was relatively simple. He filled up a yoga ball with carbon monoxide but, when he tried to place it in the boot of the Mini, he found he was unable to close it. Accordingly, he let out some of the contents in order to fit it into the boot, removed the stopper and recorded the diffusion rate. 67.Dr Wong found there were variables which affected the amount of carbon monoxide inside the vehicle; for example, opening a door. A later test was to reveal a huge leakage of gas once the doors were opened[76]. It should be remembered that the window of the Mini had been smashed when the police arrived and, at the time of the tests, it had simply been covered. The Judge reminded the jury that the carbon monoxide concentration would have been higher on the day the deceased died before the window had been broken[77]. 68.Professor Li, for the defence, used a different Mini Cooper of the same year and model for his experiments. He also found that a yoga ball with a volume of more than 65 litres would not fit into the car[78]. Instead of carbon monoxide, Professor Li used nitrogen, which has the same density, for his tests. 69.Mr McCoy, in his closing address to the jury, made the point that if someone was aware of how dangerous carbon monoxide was, he could not have safely squeezed it into the boot; whereas, “someone who doesn’t understand how dangerous it is may well have done it. It’s a ridiculous notion … somebody standing there with their hand, the lid halfway down, trying to squeeze it out”[79]. 70.Professor Li was critical of Dr Wong’s methodology, describing it as misleading. His main complaint was that the yoga ball would not have deflated at a constant rate. He also observed that when one of the doors of the Mini was opened, there had been a huge drop in carbon monoxide concentration. The diffusion rate of carbon monoxide: the timeline defence 71.There was no dispute that both Madam Wong and Lily had died from carbon monoxide poisoning. As we have already mentioned, the carbon monoxide concentration in the blood of Madam Wong was 50%; and in Lily, 41%. The way the car came to rest, with its rear protruding out into the road, suggested that the carbon monoxide concentration must have affected Madam Wong’s ability to drive properly[80]. 72.The defence sought to show, from the evidence of the diffusion rate, that the yoga ball must have been put in the car shortly before they left the house, suggesting that it could not have been the applicant who placed it there, since he was teaching at the time. Professor Li testified that there had been a 40% reduction of volume in the first half hour of his test[81]. 73.Siti testified that Madam Wong had taken the children to school at 7:30 am and returned home at 8:30 am. At about 10:00 am she had gone upstairs. According to his video recorded interview, the applicant did not have to go into work too early, but he did have to attend a student’s presentation at the Chinese University at about 1:30 pm[82]. The admitted fact dealing with this matter did not specify the exact time but merely averred that the applicant was at a presentation on 22 May 2015[83]. Furthermore, he was on duty at about 4:00 pm later that day in an operating theatre[84]; and it was while he was working, of course, that he received news about his wife and daughter. 74.The Judge noted in her summing-up that the window of opportunity for the applicant to have put the yoga ball in the Mini was between the time when Madam Wong returned from dropping the children at school, and before he left to do the presentation at the Chinese University[85]. She pointed out that the jury might have thought it unlikely he could have put the yoga ball in the car before 10 am, since Madam Wong was in the garden admiring flowers or playing on her mobile telephone in the sitting room[86]. 75.Siti stated that she saw Madam Wong and Lily walking to the Mini carrying nothing, certainly not a yoga ball. Siti said it was raining at that time and the car was not parked under cover, indicating that one would get wet when getting into the car; although the Hong Kong Observatory records suggested it did not start raining until 3:00 pm. This was all relevant in weighing up how long it would have taken someone to get into the car in such conditions and how long the yoga ball might have been there. Madam Wong had only managed to drive the car for 1.6 kilometres. 76.Accordingly, the jury were required to consider the expert evidence against the factual matrix, in deciding when the yoga ball might have been placed in the Mini, and by whom. An overview of the grounds of appeal 77.In order to have an overall appreciation of how this appeal has been presented and argued, it is necessary briefly to examine the litany of complaints and points which have been made by and within the numerous grounds of appeal. In the course of this overview, we will make some obvious responses and general remarks which will be followed, where appropriate, by a more detailed discussion in respect of the specific complaint or point that is being addressed. 78.The grounds of appeal have been grouped under four general headings[87]. The first general heading is “Burden and standard of proof/approach to defence evidence/right to silence”. There are in total 11 grounds of complaint under this heading. (i) Proof, defence evidence and the right of silence 79.Ground 1 complained that the Judge misdirected the jury as to the burden and standard of proof in that: (a) her directions suggested there was a burden on the defence requiring, variously, “reliable evidence” or evidence “of sufficient reliability and strength” or “good evidence” in order to cast doubt or destroy the prosecution case; and (b) her directions on speculation erroneously suggested that identical burdens and standards of proof applied to both the prosecution and the defence. 80.We are of the view that there was nothing improper in what the Judge said when they are read in context. She gave the correct directions to the jury on the burden and standard of proof in accordance with the Specimen Directions in Jury Trials, promulgated by the Hong Kong Judicial Institute, and went into considerable detail in explaining their task and function as judges of fact[88].The references to “reliable evidence” or “good evidence” in the context in which they were given did not shift the burden of proof as alleged. 81.Ground 2 suggested that the Judge misdirected the jury as to the burden and standard of proof by: (a) effectively inviting the jury to choose between the evidence of the experts whose evidence was conflicting; (b) reducing the issue of whether there was a rodent problem at the applicant’s home to a choice between the evidence of Siti and the applicant; (c) reducing the question of whether blood had been reinjected into rabbits during the preliminary experiments conducted to a choice between the evidence of Dr Dick Chow and Professor Wang; and (d) directing the jury about the conflicting prosecution and defence evidence as to whether it was raining, without reminding them that the defence evidence which might be true would suffice to create a reasonable doubt. 82.In our view, the Judge fairly presented these issues by setting out very clearly the factual and contextual bases in which they arose. The jury were consistently reminded that it was a matter for them how they assessed and evaluated the evidence in resolving the issues they were to consider. The differences in the expert evidence and the issues to which they related were delineated by the Judge, and this included whether reinjection took place in the two experiments. The Judge also canvassed the issue in respect of the rodent problem at the applicant’s home and the method of exterminating them by releasing carbon monoxide from the yoga ball; and the question of whether it was raining when Madam Wong and Lily got into the car. 83.Ground 3 contended that the Judge failed to direct the jury to acquit the applicant if his exculpatory statements in his video recorded interviews might be true. 84.However, in our view, the Judge gave a clear and precise direction that if the account put forward by the defence “is or may be true”, they should find the applicant not guilty[89]. The Judge also stressed the applicant’s good character both in terms of credibility and propensity in respect of his answers in the video recorded interviews[90]. 85.Ground 4 averred that the Judge wrongly directed the jury in respect of the drawing of inferences to the effect that: (a) Madam Wong’s ignorance of the fact that the yoga ball contained carbon monoxide was a reason for excluding her as the person who put the yoga ball in the car; (b) if there was no stopper for the yoga ball in the car, Lily could in effect be ruled out as the person who placed the yoga ball there because there was no reason for her to throw away the stopper; and (c) the jury might infer that it was raining from the fact that the windscreen wipers were on when the car was found, when it was equally likely that the wipers had been switched on clumsily and accidentally. 86.In our view, these were all valid propositions arising from the evidence for the jury to consider, particularly as to whether Madam Wong or Lily had put the yoga ball in the car. It was the defence suggestion that Lily may have put the yoga ball there because of her phobia of insects. In order to assist the jury, the Judge gave the appropriate directions on circumstantial evidence and inferential reasoning. She clearly explained how inferential reasoning worked and how it could be employed in order to assist the jury to make findings of fact. The Judge emphasised that it was for the jury to consider and ultimately resolve the issues mentioned. She also told them that they were free to reject any view she might express on the evidence unless it accorded with their own view of the evidence[91]. 87.Ground 5 complained that the Judge failed to direct the jury not to draw an adverse inference from the applicant’s failing to tell the police that the yoga ball contained carbon monoxide, and to remind them of the applicant’s right to silence. 88.We are of the view that the issue of the applicant exercising his right of silence, did not arise, as he voluntarily answered initial inquiries by the police and he subsequently acknowledged that he failed to disclose relevant information to them. Furthermore, no point was taken at trial that the applicant had a right of silence or was purporting to exercise it at the time he was answering initial inquiries from the police. We shall deal with this ground in greater detail later. (ii) Failure to summarise the defence case 89.The second general heading is “Failure to summarise the defence case/unbalanced summing-up/inaccurate summing-up”. There are in total 9 grounds of complaint under this general heading. 90.Ground 6 alleged that the Judge failed to remind the jury of the defence case that the timeline and possible levels of carbon monoxide concentration meant that if the applicant had placed the yoga ball in the car, the carbon monoxide level would have been such that Madam Wong could not have been overcome so quickly. 91.In our view, this complaint cannot be justified. The Judge comprehensively set out the evidence and the respective cases of the prosecution and the defence, referring in detail to the criticisms of the prosecution case and the range of possibilities as to what might have happened as submitted by the defence. More particularly, she referred to the factual matters and empirical data relating to the possible levels of carbon monoxide concentration as well as the times of relevant events and other factors for the jury to consider[92]. It was accepted by Mr McCoy in his closing address that there were a number of variables and unknowns in the case which the jury had to bear in mind when assessing the evidence and the propositions he was putting forward for their consideration. 92.Ground 7 contended that the Judge failed to remind the jury that the applicant’s research was genuine, and in particular failed: (a) to summarise the defence case as to the extra haemoglobin effect hypothesis, by directing the jury that Professor Wang had not addressed the matter and that it was not important; and (b) to remind the jury of the defence case that the focus of the research was not on carbon monoxide or carbon monoxide poisoning but on supplemental oxygen and tissue hypoxia. 93.The Judge presented an extensive overview of the scientific evidence in respect of the applicant’s research, and hence the subject of this complaint only focuses on a small aspect of it. The overview was in fact very detailed and appropriately addressed the evidence and the salient issues at trial[93]. This included the evidence as to the extra haemoglobin effect hypothesis and the nature and terms of the research protocol. Relevantly, one issue before the jury was whether the applicant’s research was a sham, and even if it was not, whether it was a means by which he sought to obtain carbon monoxide. The Judge, on several occasions, reminded the jury of the defence case that the applicant’s research was genuine and that he openly engaged in experimenting with carbon monoxide[94]. 94.Ground 8 argued that the Judge incorrectly summarised the evidence as to whether blood was reinjected into the rabbits when choosing between the evidence of Dr Dick Chow and Professor Wang. 95.It was highly relevant that Dr Dick Chow was involved in the two experiments and therefore able to give a first-hand account of what took place, whilst Professor Wang was not involved. We cannot see how the Judge can be criticised for noting this fact for the jury to consider when addressing this issue. In any event, the jury were well aware of the difference in the evidence between the prosecution witnesses (Dr Dick Chow and Ms Tam) and the defence expert, Professor Wang, as to whether reinjection took place when the two experiments were conducted. Professor Wang’s evidence was an opinion based on his interpretation of the carbon monoxide oximeter readings. 96.Ground 9 complained that the Judge’s summing-up was unbalanced in repeatedly stating or implying that “a crime” had been committed. 97.The applicant stood accused before the jury of having committed the crime of murder. There would have been no conceivable misapprehension or misunderstanding on the part of the jury that they were to determine whether the applicant was guilty or not guilty of the murder of Madam Wong and Lily. The reference to “a crime” would not have impacted adversely on the applicant. We would add that no complaint was made by leading counsel for the applicant at trial about this matter. We shall deal further with this ground later. 98.Ground 10 suggested that the Judge misdirected the jury as to the financial benefit to the applicant in the event of Madam Wong’s death. There is no substance in this complaint. This issue was appropriately dealt with by the Judge in her summing-up. The jury heard evidence as to the financial status of the applicant and Madam Wong and they were reminded of the defence case on this issue in the closing address of leading counsel. The Judge, in any event, explained that the financial information was included in the admitted facts and that there was no evidence that the applicant wanted to get rid of his wife in order to get the money. She told the jury: “So that is another aspect that you have to consider; no apparent motive for the defendant to kill his wife”[95]. 99.Ground 11 concerned the Judge’s directions in respect of the stopper to the yoga ball. 100.It is complained that the Judge misdirected the jury as to the yoga ball stopper and whether it was missing on 22 May 2015[96] by: (a) omitting to mention possible errors and the unreliability of the exhibits officer in not finding the stopper; (b) omitting to direct on the possibility that the stopper had been mishandled or misplaced in the six months which had elapsed before the exhibits officer had searched the Mini, and inviting the jury to speculate as to whether the stopper was missing when Madam Wong and Lily were found; and (c) directing the jury that if they were sure there was no stopper, there was no reason for Lily to throw it away but omitting to mention that if it had been the applicant, he too would have had no reason not to leave the stopper in the Mini. 101.We will address this ground in greater detail later. The points raised by the applicant about the exhibits officer’s handling of the exhibits and possibly misplacing the stopper were canvassed by Judge in her summing-up. We are satisfied that the Judge properly summed up the evidence on this issue. (iii) Removal of issues from jury 102.The third general heading is “Removal of issues from jury”. There are in total 5 grounds of complaint under this general heading. 103.Ground 12 alleged that the Judge erred by effectively removing the issue of unexplained accident from the jury and in doing so: (a) usurped the function of the jury; (b) placed a burden on the defence to prove the applicant’s innocence; and (c) failed to leave the defence case of unexplained accident to the jury. 104.There is simply no substance in this complaint. In short, the prosecution case was that the applicant had placed the yoga ball in the Mini and released the carbon monoxide from it, knowing his wife would be using the car. As part of the defence case, alternative possibilities were presented to the jury, principally that Lily put the yoga ball in the car because of her phobia of insects. The Judge made it abundantly clear to the jury, without demur from the defence, that the main issue for them to decide was who put the yoga ball filled with carbon monoxide inside the Mini and why[97]? The Judge also reminded them that in addressing the two counts of murder against the applicant, they had to consider the ingredients of the offence, and whether they were sure that he put the yoga ball in the Mini and removed the stopper, so that the carbon monoxide leaked into the cabin of the car. If they were not sure, then the prosecution case had failed[98]. There was a strong case against the applicant that it was he who placed the yoga ball in the Mini. In his closing address to the jury, Mr McCoy stated: “Now, let me tell you straight away the defendant in this case is morally responsible for the deaths of his daughter and wife. If that guy had not brought that home, it couldn’t have been there for it to end up in the car.”[99] Although the case against the applicant was strong, leading counsel raised other possibilities as to who might have placed the yoga ball in the car and why[100]. 105.The applicant relied on R v Henderson and Others [101]for the proposition that there was a realistic possibility of an unknown cause of death in the present case and the jury should have been reminded of that possibility. Henderson and Others involved three appeals which concerned what is termed ‘shaken baby syndrome’, where the cases turned solely on the evidence of experts. Whilst expert evidence featured predominantly in the present case, it was not the sole evidence on which the case fell to be determined. The cause of death was known and the issues between the respective experts were clearly defined. The focal point at trial was who put the yoga ball in the Mini and released its deadly contents. 106.We are bound to say that there was little if any evidential basis to support a realistic possibility that the deaths of Madam Wong and Lily were an accident. The applicant had filled two yoga balls with carbon monoxide and stored them overnight in the Toyota Alphard, placing carbon monoxide detectors inside the vehicle. The next day he found one of the yoga balls had released its contents of carbon monoxide but took the other yoga ball to his home residence. According to the applicant, he was intending to release the deadly gas to kill rodents at the home. He said he left the yoga ball in his home for that purpose and went off to work. He did not install any carbon monoxide detectors at home, nor did he warn anyone about the deadly contents of the yoga ball, except to tell Lily that it contained a poisonous gas, with which he intended to kill rats over the weekend[102]. The yoga ball ended up in the Mini and its poisonous gas was released, killing Madam Wong and Lily. Clearly someone put the yoga ball in the Mini and removed its stopper. 107.Despite the applicant’s complaint in this ground, we note the Judge left the defence argument that the death of Madam Wong and Lily was an accident for the jury to consider. When taking the jury through the evidence, she told them that they “may think” they could eliminate Madam Wong and Lily as being responsible for putting the yoga ball in the Mini. However, she also reminded them of the defence suggestion that Lily was experiencing difficulties and may have accidentally killed herself and her mother because she wanted to kill insects inside the Mini[103]. 108.Ground 13 complained that the Judge erred in directing the jury that the yoga ball was in the car before Madam Wong got into it, thereby usurping the function of the jury and removing from them the defence case that it might have been done by Madam Wong or Lily. 109.The evidence of Siti was that she observed Madam Wong and Lily were not carrying anything with them when they got into the car. The Judge carefully guided the jury through the evidence as to whether Siti, Madam Wong or Lily may have placed the yoga ball in the car as well as addressing the case for and against the applicant[104]. As already noted, the Judge reminded the jury of the defence argument that the death of Madam Wong and Lily was an accident as well as reminding the jury of Lily’s character and fear of insects, which were relevant to the defence theory of Lily having attempted to kill insects inside the Mini[105]. There is simply no merit in this complaint. 110.Ground 14 contended that the matters set out in Grounds 6 to 13 resulted in the summing-up being unbalanced in that it so undermined the defence case as to be tantamount to a second prosecution closing address. 111.Mr Grounds took issue with the Judge’s directions in respect of (i) Dr Wong’s evidence concerning the gas concentration and dissipation in the Mini and the criticisms of his tests by Professor Li; (ii) the level of carbon monoxide in the Mini under certain conditions, such as if it was raining and if the car window was broken; (iii) the exhibits officer’s evidence about not finding the stopper to the yoga ball and Lily having no reason to throw the stopper away if she put the yoga ball in the Mini; and (iv) the rat problem at the family home and May May’s evidence on this issue. 112.These matters were mentioned by the Judge in her summing-up. She addressed the evidence of Dr Wong and Professor Li and the tests they had performed. She discussed the levels of gas concentration and dissipation in the Mini as variously explained by the experts. She referred to the challenge to the exhibits officer’s evidence and the issue as to his reliability of what he found in the Mini. She summarised the evidence of May May and took the jury to the defence photographs of the home in relation to the rat problem[106]. 113.In our view, this ground is unarguable: the summing-up was plainly not unbalanced, nor did it conceivably amount to a second prosecution closing address. 114.The fourth general heading concerns “Expert evidence”. There are no less than 19 grounds of complaint under this general heading. 115.Ground 15 alleged that the Judge failed to summarise the expert evidence correctly, nor was her summary properly balanced. 116.This complaint is expressed in extreme language and is without substance or justification. There is no basis to suggest that the Judge’s summary of the expert evidence was unbalanced. In our judgment, the Judge gave a very comprehensive summary of the expert evidence, which properly reflected the salient matters and issues raised by or between the respective experts. 117.Ground 16 complained that the Judge in respect of the expert evidence of the applicant’s research: (a) wrongly suggested that only Professor Buckley disputed the validity of the hypothesis in relation to the extra haemoglobin effect when Professor Wang had also done so; (b) erroneously directed the jury that as the applicant had not given evidence there was no evidence that blood had been reinjected into the rabbits and did not remind the jury of the applicant’s statements on the matter in his first video recorded interview; (c) failed to direct the jury that Professor Kwong’s conclusions were vitiated to the extent they were based on hearsay as to whether reinjection had occurred; (d) failed to summarise Professor Wang’s evidence by omitting to mention the significance of the research; (e) failed to instruct the jury as to the clinical relevance of the research; and (f) stressed procedural and formal criticisms concerning the research by: (i) unfairly contrasting the bulk of exhibits P62 and P63 with the “slim protocols” for the research (exhibits P113A, B and C); (ii) directing the jury to consider whether the applicant and his research protocols should have justified the methodology of extracting blood from rabbits, rather than focusing on the stated purpose and the opinions as to the value of the research. 118.This ground essentially focuses on the issue of the genuineness of the applicant’s research involving carbon monoxide. The complaints under this ground are not justified and we have concluded that the Judge very fairly summarised the evidence and identified the relative arguments of the parties in respect of this issue. The specifics of this ground will be addressed later in the judgment. We shall also refer to the relevant parts of the Judge’s summing-up in respect of the applicant’s research, because it reveals that the matters now complained about by the applicant were fully and properly addressed by the Judge. 119.Ground 17 contended that the Judge failed to sum up the expert evidence as to the rate of deflation of the yoga ball, the levels of carbon monoxide in the Mini and the rate of diffusion or dissipation of the carbon monoxide, and consequently as to the relevant timeline, in that she: (a) erred in directing the jury as to the actual carbon monoxide concentration in the Mini on 22 May 2015, which would have been higher when allowance was made for leakage from an imperfectly sealed broken window of the car; (b) summarised the evidence of Professor Li in a confusing and inaccurate manner; (c) erred in directing the jury to consider photographs 4 and 5 of exhibit P121, which showed the yoga ball in different positions in the boot of the Mini, when deciding how the yoga ball had deflated, because: (i) the photographs had been taken several hours after the discovery of the deceased in the car, but there was no evidence as to which photograph had been taken first; (ii) there was no evidence as to the position or state of the yoga ball when the deceased were first discovered; and (iii) it was apparent that the yoga ball must have been handled at least between the taking of photographs 4 and 5; (d) erred in directing the jury that they could choose between the evidence of Dr Wong and Professor Li as to the test performed about deflation, leakage and dissipation; and (e) failed to provide proper guidance as to the tables relied on by Dr Foo Ka Chung (PW31) (“Dr Foo”) and Dr Wong as to the effects of exposure to carbon monoxide in different concentrations and for different periods, and did not properly remind the jury of the defence case as to the timeline. 120.This ground is concerned with the timeline defence, which to the extent it was argued at trial, was properly addressed by the Judge in her summing-up to the jury. Most of the points raised by this ground were part of the factual matrix set out by the Judge in her summing-up. This is another ground where we will have to recite in full the relevant passages of the Judge’s summing-up in order to dispel the criticism that the Judge did not fairly or properly present the defence case on this point. 121.Ground 18 complained that the Judge failed to direct the jury that since the evidence was circumstantial, if there was a reasonable explanation of the facts consistent with innocence, they should find the applicant not guilty. 122.The Judge not only gave the standard directions to the jury on inferential reasoning, but also repeated, when it was contextually relevant, that an adverse inference could only be drawn against the applicant when it was the only reasonable inference from the facts proved[107]. She explained to the jury that in addressing a circumstantial case they should “consider whether the evidence upon which the prosecution relies in proof of its case is reliable and whether it does prove guilt, or whether on the other hand it reveals any other circumstances which are or may be of sufficient reliability and strength to cast doubt upon or destroy the prosecution case.”[108] 123.Ground 19 averred that the Judge failed adequately to: (a) direct the jury as to how to approach the expert evidence and how to identify areas of dispute; (b) summarise clearly and in a balanced manner the evidence for and against the propositions advanced; and (c) provide guidance to the jury as to how to evaluate conflicting expert evidence, explaining the basis for distinguishing reliable from unreliable evidence. 124.This is a general complaint without any substance. The Judge gave a comprehensive summing-up in respect of the expert evidence and the jury would have been well aware of the issues and matters they had to consider and resolve. 125.The last ground of appeal, Ground 20, was in general terms and asserted that in all the circumstances of the case the applicant’s convictions were unsafe and unsatisfactory. It was contended that the applicant was deprived of a fair trial and there remained a lurking doubt as to the correctness of his convictions. The form and content of the grounds of appeal 126.As we have already noted, no less than 20 numbered grounds of appeal have been advanced in this matter. However, several of the grounds have sub-grounds and sub-sub-grounds, which are in many cases separate and discrete complaints, and which in reality take the overall number of grounds to more than 40 grounds of appeal spanning some 22 pages. The grounds are contained in a document entitled Amended Perfected Grounds of Appeal Against Conviction, signed by counsel, Mr Christopher Grounds and Mr Andrew Bullett, who, together with Mr Franco Kuan, represented the applicant at the appeal. All three counsel were new to the appeal, as were their instructing solicitors. We wish to say something about the form and content of the grounds of appeal in this case, since they demonstrate a growing and unacceptable trend in appeals before this Court. It is necessary to remind practitioners that an appeal should identify only those errors of ultimate fact or law which affected the result. It should not condescend into complaints about minutiae or espouse new and unsupported theories about the case. 127.We must begin by reciting and emphasising section 7(1) – (8) of Practice Direction 4.2 concerning Criminal Appeals to the Court of Appeal (“PD 4.2”), which was signed by the Chief Justice on 19 February 2019, and came into effect on 11 March 2019. Under the heading ‘Perfected Grounds’, section 7(1) – (8) of PD 4.2 stipulates:
128.With respect to counsel’s endeavours, and acknowledging that the case was lengthy, albeit, we think, not unduly complex, the Amended Perfected Grounds of Appeal infringe almost all of the above sections of the Practice Direction. Firstly, what we assume was an attempt to provide “a brief statement of the key issues at trial relevant to the application or appeal” (in accordance with section 7(4) of PD 4.2) in fact runs to 8 pages and goes far beyond what was necessary to state the key issues at trial; one of which, for example, was that there was a conflict of expert evidence as to when the yoga ball may have been placed in the Mini so as to overcome the occupants by carbon monoxide poisoning. Instead, there is an extensive analysis of the respective expert evidence to the following effect:
129.On another issue of whether the applicant’s research was a sham or genuine, an issue which could likewise have been expressed in a single sentence, the Amended Perfected Grounds of Appeal again contain a detailed analysis of the respective experts as follows:
130.All, with respect, that was needed was a short, concise statement of the essential issue to which the grounds related. Such issue could have been stated, as we have done, in one sentence. 131.Secondly, some of the grounds themselves are peppered with comment and submission. Plainly, they do not in any way comply with the requirement that the complaint constituting the ground of appeal should be stated “as concisely as possible” (as stipulated by section 7(6) of PD 4.2). While section 7(6) states that “[i]t should not normally be necessary to state the point in more than one or two sentences”, we accept that occasionally, it may be necessary to go further. This is not such an occasion. Ground 16, for example, reads as follows:
While Ground 17 is pleaded as follows:
132.The prolix form of these (and, indeed, other grounds) raise a third concern, which is that some of the grounds put forward are in fact a number of different grounds masquerading as a single ground of appeal. Ground 16, for example, complains of the Judge’s misstatements of fact, her many failures to remind the jury of evidence, her favourable treatment of prosecution evidence, her prejudicial comparison of the parties’ expert evidence and her failure to exclude hearsay evidence. Ground 17 makes the same complaints, but in addition avers that the summing-up was confusing as well as inaccurate, failed to give proper guidance to the jury and erred in law by allowing the jury to “choose between the evidence of” a prosecution and a defence expert witness, an issue which goes to the burden and standard of proof. 133.Fourthly, there is considerable repetition and obvious overlap between the various grounds of appeal. For example, Ground 16(d), which complains of an incorrect direction as to the burden and standard of proof where expert evidence was in conflict, is already part of Ground 2(a). Ground 4, which takes issue with the inferences in respect of who might have put the yoga ball in the Mini, overlaps with Grounds 12 and 13, which complains that the Judge suggested that Madam Wong and Lily could be eliminated as suspects. Ground 6, which takes extensive issue with how the jury were directed on the evidence about the diffusion rate of carbon monoxide, is much the same as Ground 17(a) – (e), in particular Ground 17(e), and Ground 19(a) – (c). 134.Ground 1, which complains about the directions on the burden of proof, inferences, and how the Judge wrongly placed a burden of proof on the applicant is virtually the same as Ground 18 and substantially overlaps with Ground 3. Ground 7 focuses on the applicant’s experiments on rabbits and the Judge’s directions thereto, which in substance are the same allegations in Ground 16(a) – (f). Ground 14, which is a complaint of an unbalanced summing-up, has significant overlap with Ground 6 and the complaints concerning the timeline defence; as well as with Ground 4 concerning inferences, one of which concerned whether or not it was raining. And Ground 8 overlaps considerably with Ground 16(b) and (c), which concerns whether or not blood was reinjected into the rabbits. 135.We must make clear that if, in future, perfected grounds of appeal are filed which do not, as these grounds manifestly do not, comply with PD 4.2, they will be “returned for correction with a direction that the case be not listed until a compliant set of perfected grounds is filed” (as stipulated by section 7(8) of PD 4.2). 136.There are a number of important reasons why this Court must insist on perfected grounds of appeal being filed properly and in accordance with PD 4.2. The first important reason is that the Court of Appeal is an appellate court, not a trial court. Much of counsel’s arguments in this appeal were involved with solely factual matters, or arguments as to why the evidence of one witness undermined that of another witness, or why one piece of evidence should have been accepted and another rejected. And, on several occasions during the appeal, defence counsel seemed to be making a jury speech to us. The discipline of PD 4.2 requires appellate counsel to focus on “properly arguable” grounds of appeal which have a reasonable prospect of unsettling the conviction (or reducing the sentence). Appellants are not on trial: they have already been convicted. It therefore behoves appellate counsel appealing against conviction to identify, not why the appellant should not be convicted, but why the conviction should be set aside as unsafe and unsatisfactory, or because of a wrong decision on a question of law, or because of a material irregularity in the course of the trial. 137.The following grounds of appeal demonstrate complaints that were entirely without substance and simply not properly arguable. 138.It was argued before us, in a 19-page Reply signed by Mr Grounds and Mr Kuan, that it was “an admitted fact of great significance” that the applicant did not use his key to the Mini on the date of the offence[109]. Therefore, “it had to be either Madam Wong and/or Lily who had put the yoga ball in the Mini for a yoga related purpose, pesticide, suicide or any other reason. It was an unfortunate and unexplained accident. The applicant is innocent”[110]. In argument before us, it was submitted that since it was an admitted fact that “the last updated record for the car key of Deceased 1 (Madam Wong), Exhibit 2 was at 14:18 on 22 May 2015”, it could not have been the applicant who placed the yoga ball in the boot of the Mini[111]. 139.This argument is not adverted to anywhere in the 20 Amended Perfected Grounds of Appeal: it came in by way of the applicant’s Reply and fell to Mr Kuan to present it. Yet, the point made before us on appeal was never one engaged by either leading counsel at trial: for the defence, the one reference to the time on Madam Wong’s key in Mr McCoy’s speech to the jury was in the context of trying to establish a rough time at which Madam Wong and Lily must have got into the car and arrived at the bus stop[112]. Nor was the issue, which is now said to be so significant and demonstrative of the applicant’s innocence, regarded as such at trial, no doubt for the very simple reason that there was no evidence as to whether the Mini was locked or, if it was, when it was unlocked, prior to Madam Wong and Lily setting off to pick the two children up from school, or what, in technical terms, “the last updated record for the car key of Deceased 1” actually meant; for example, whether it recorded the time of the unlocking of the car, the turning on of the engine or, even, the turning off of the engine. With respect to counsel, this is not a submission (let alone a ground, which it was not) that should have been put forward on appeal before this Court. 140.Mr Grounds then took specific issue with the Judge’s expressed or implied references to the fact that a “crime” had been committed (Ground 9), notwithstanding that some of the references are verbatim recitals by the Judge of standard Specimen Directions making reference to the commission of “the crime” (for example, in relation to circumstantial evidence). The jury would have been well aware that it was the prosecution case that the applicant had murdered his wife and daughter; and that it was the applicant’s case that he had had nothing to do with their deaths, which may simply have been a tragic accident. No one reading the summing-up as a whole could conceivably have thought that the Judge was putting the case against the applicant any higher than an allegation by the prosecution and it is frankly absurd to suggest otherwise. 141.This ground should never have found its way into the Amended Perfected Grounds of Appeal to be argued before this Court. 142.It was further argued that the Judge’s reference to the applicant’s and Madam Wong’s financial arrangements misdirected the jury that there may have been a financial motive on the applicant’s part for killing his wife (Ground 10). However, there were Admitted Facts as to the parties’ financial arrangements[113] and the Judge was making a point, in a section dealing with the absence of motive on the part of the applicant[114], that was in fact in favour of the applicant. She said[115]:
No complaint was made at trial about the Judge’s direction by leading counsel for the applicant and one can readily understand why. Read properly and in context, it forms part of a section in the summing-up that was actually favourable to the applicant, inasmuch as it instructed the jury that there was no evidence that either mistress or money were motives for the applicant to kill his wife. 143.Yet, Mr Grounds submitted that the mere mention of this matter, notwithstanding that the evidence was contained in the Admitted Facts, had the contrary effect on the jury, for it “excited” by way of “innuendo” the possibility that the applicant did have a financial motive for killing his wife. This argument is wholly untenable and unrealistic, and flies in the face of what the Judge was at pains to make clear in the applicant’s favour. It, also, is not a properly arguable ground of appeal. The burden and standard of proof 144.Equally unarguable is the submission made under Ground 2(a) and (c) that the Judge misdirected the jury as to the burden and standard of proof, by inviting the jury to choose between the evidence of the experts, when it may not have been possible to reach a firm conclusion as to who was right and who was wrong. The Judge in fact gave the standard direction on expert evidence, in accordance with Specimen Direction 32. She said[116]:
145.At the commencement of her summing-up, the Judge had given a general direction on how the jury were to approach the evidence of witnesses[117]:
146.The argument that the jury may somehow, despite these directions, have decided that they must accept one or other of the experts where their evidence on a particular issue was in conflict is an untenable proposition, as well as wholly unrealistic in the context of a trial where the jury would have well understood the areas of agreement and disagreement between experts. Again, with respect, this argument should never have found its way into this set of grounds of appeal. 147.A second important reason why practitioners must comply with the discipline of PD 4.2 when filing grounds of appeal is that where, as here, appellate counsel are new to the case, their duty to settle grounds which are properly arguable may require them to consult previous trial counsel. In HKSAR v Apelete (No 1)[118], this Court made it clear that:
Fresh counsel at an appeal, particularly where the solicitors are also new to the case, will seldom have a full appreciation and proper understanding of the dynamics of the trial and the real issues between the parties, and the tactical and forensic decisions employed by trial counsel in conducting the defence, which are usually derived from trial counsel’s anticipation of what witnesses are likely to say in accordance with their depositions, from their assessment of the actual evidence as it emerges, from their perception of how the jury is receiving that evidence, from their instructions and, sometimes, from their discussions with the prosecution either inside or outside court, unless they ask trial counsel. 148.The difficulties which arise when fresh counsel on appeal advance new arguments impugning the conduct of the defence case at trial has recently been discussed in HKSAR v Abedin Minhajaul[119]. In that appeal, defence counsel was required to appear before the appellate court to explain his conduct of the defence case at trial, notwithstanding that no complaint of flagrant incompetence had been levelled against him by the appellant’s new legal team. Macrae VP identified two particular problems that commonly arise in such circumstances:
149.Consulting trial counsel would have been an important step before advancing Ground 5, in which Mr Grounds questioned before us Mr McCoy’s decision to leave the passages in the first video recorded interview of the questions and answers between DSgt 16404 and the applicant as to why he did not tell the officer about the missing yoga ball, or the fact that it was full of carbon monoxide, at their meeting at the applicant’s home a year earlier. Mr Grounds has maintained that he would have asked for the passages of the interview in question to be redacted, although he initially accepted before us that they are not inadmissible. 150.Mr Grounds quite properly did speak to Mr McCoy about the matter. Accordingly, he was able to inform us that Mr McCoy had made a specific decision that he did not want the impugned passages excised from the record of interview. We will return to the significance of this matter when we deal with Ground 5 in due course. 151.The third reason that PD 4.2 must be properly complied with is that it will concentrate the minds of counsel for the applicant and the respondent, as well as the Court itself, on the real and significant issues which fall for consideration at the appeal. The Court is not assisted by jury points masquerading as legal argument, or by a multitude of repetitious, unfocussed or plainly inconsequential grounds of appeal which fail to recognise how and why the trial was conducted in the way it was, or cannot sensibly affect the outcome. We venture to suggest that many of the grounds of appeal in this case could not have been put forward by leading counsel at trial, who, despite his experience and stature as a criminal practitioner, made no complaint whatsoever about the summing‑up. Moreover, it seems to us, with respect, that several of the grounds put forward by fresh counsel at the appeal do not reflect a proper appreciation and understanding of the real issues engaged at trial. 152.For these reasons, which this Court forecast in HKSAR v Chung Chun Fung and Another[120], we wish to state the position for all future appeals in murder cases. Hitherto, there has been a practice by which applications for leave to appeal against conviction for murder have been dealt with at the same time as the hearing of the appeal proper, rather than going through the Single Judge leave application process. This routine practice will now cease and all appeals against conviction for murder, where issues of fact or mixed law and fact are concerned, must be dealt with in the same way as any other appeal requiring a separate leave application before a Single Judge, in accordance with the Practice Direction, unless the Single Judge orders otherwise. Had that happened in the present case, most of the 20 grounds of appeal (in reality, some 40 grounds of appeal) would have been refused leave to appeal as not being reasonably or properly arguable, which ought to have resulted in the streamlining of the appeal as well as the focussing of counsel’s oral submissions. 153.We have been concerned for some time, and this case further illustrates our concern, with allegations made at appeals by fresh counsel on appeal, which too readily question the conduct of trial counsel: some go so far as to allege flagrant incompetence, others stop short and are merely critical of decisions taken by trial counsel, which appellate counsel maintain they would not have taken. Again, these allegations are often made without a proper understanding of the real issues at trial and the tactics employed by trial counsel to deal with them. We would respectfully endorse the recent comments of the Court of Appeal of New South Wales, presided over by Bathurst CJ, in Roach v The Queen[121]:
154.Although we are critical of the form and volume of the grounds of appeal filed in this case, many of which are plainly “armchair” grounds of appeal, we wish to make clear that such criticisms are by no means confined to this particular case; which is why we have considered it necessary to give clear guidance to the profession in conducting future appeal cases. Moreover, such criticisms as we have made do not in any way affect the obligation of the Court to address the issues raised by this appeal, which were fully, comprehensively and, if we may say, articulately addressed by the applicant’s counsel in the course of a two-day appeal. Although there were many grounds of appeal which were plainly not reasonably or properly arguable, there were some grounds which were. The danger of fresh appellate counsel putting everything they can think of into a set of grounds of appeal, without the distillation which should come with appellate counsel’s expertise, is that the arguments sometimes “lose sight of the wood for the trees”, and that grounds which may have individual merit become lost in a morass of unmeritorious and inconsequential grounds of appeal and argument. One of the more arguable grounds to emerge in this appeal was that concerning the alleged infringement on the applicant’s right of silence (Ground 5). However, looking at the way the Amended Perfected Grounds of Appeal were drafted by counsel, and the short single paragraph it merited in the accompanying written submissions[122], one does not immediately appreciate its significance. Indeed, at the end of argument concerning Ground 5, even Mr Grounds was moved to say of this particular ground, “it may be that the point is much, much bigger than even I had thought of … as one of the grounds”. Given that it became such a prominent point of argument, we shall begin by addressing this matter in greater detail. The applicant’s right of silence 155.The complaint in Ground 5 is that the Judge was wrong to remind the jury of the applicant’s failure to tell the police in his early dealings with them about the missing yoga ball containing carbon monoxide and his connection with it, without at the same time directing the jury not to draw adverse inferences from such failure, and without directing them that the applicant had a right of silence. Thus put, it was not averred that the evidence was inadmissible per se: indeed, Mr Grounds, in answer to a specific question from the Court, originally accepted that the particular impugned answers in the first video recorded interview concerning the applicant’s failure to tell the police about the carbon monoxide inside the yoga ball were not inadmissible. His complaint was that because the applicant had a right of silence, and had not therefore been obliged to tell DSgt 16404 anything about the missing yoga ball or its toxic contents when spoken to in May 2015, roughly one year before the interview, it was unfair and prejudicial to the applicant for the Judge to refer to this matter in her summing-up. 156.Before addressing this ground of appeal, we consider it necessary to set out the text of the questions and answers in the video recorded interview in question, which came towards the end of the interview. In the transcript of interview, ‘D’ represents DSgt 16404, who was one of the two interviewers, while ‘B’ was the applicant. DSgt 16404 asked first about the yoga ball[123]:
DSgt 16404 then moved to the question of why, at another meeting a few days later, the applicant had not mentioned that the yoga ball was filled with carbon monoxide[124]:
157.In their closing speeches to the jury, neither Mr Bruce for the prosecution, nor Mr McCoy for the defence, said anything at all about these exchanges; although Mr McCoy did make the comment that “the police hadn’t worked it (the source of the carbon monoxide) out for six months until when they seized the yoga ball. When did they seize the yoga ball? 22 May? No, November 2015, six months later. There’s no one accounting for the ball in the police control for six months. Who was looking in it during that six months?”[125]. The point he was making was that since the police did not realise that the yoga ball was the source of the carbon monoxide, its original position in the Mini had not been properly noted, nor had the ball been isolated or examined for some six months. One obvious rejoinder to this point is that the reason the police took six months to work out where the carbon monoxide had come from was that the one person who knew the answer chose not to tell the police. 158.The context of the passage in the summing-up about which complaint is now made was a section of the Judge’s directions dealing with what the applicant had said to the police during his arrest and questioning. Thus, the Judge began this part of her summing-up by explaining[126]:
She first dealt with the applicant’s response as recorded in DSgt 16404’s notebook, which we have recited above[127], before going through the salient features of what the applicant had said in the three video recorded interviews that followed. In that process, she reminded the jury[128]:
159.Accordingly, leaving aside for the moment the legal issue of whether the applicant had in law a right of silence at his two meetings with DSgt 16404 at his home on the night of 22 May 2015 and a few days later, the Judge was in fact doing no more than summarising the applicant’s answers in his first video recorded interview, which commenced on 13 May 2016; answers which leading counsel for the defence at trial in fact wanted to be included, and must, therefore, have accepted were admissible. Moreover, they formed part of an interview, during which the applicant not once declined to answer a single question. 160.Mr Grounds evidently disagrees with the course adopted by Mr McCoy. However, with respect, he was not counsel at trial. Mr McCoy had deftly painted the applicant as a brilliant[129], highly skilled[130] individual of positive good character[131], with an international reputation for medical excellence[132]; but also as someone who was weird in a strange way[133], nerd-like[134] and one‑dimensional[135], whose focus or concentration was abnormal[136] and tunnel-visioned[137], who was dogmatic[138] and only able to see one side of things[139], who took a narrow approach and saw things in his own way, and who lacked basic human empathy[140]. The failure to tell the police about the yoga ball or the carbon monoxide may well have corresponded with Mr McCoy’s depiction of the applicant, whose decision to bring the yoga ball home in the first place he characterised to the jury as “crazy”[141]. Moreover, we can well understand why Mr McCoy might have wanted the applicant’s answers before the jury. The explanations for not telling DSgt 16404 about the yoga ball or the carbon monoxide were not necessarily implausible or incomprehensible on a human level, given the position the applicant found himself in and the exigencies of the moment. Had the applicant felt guilty about introducing the yoga ball with its deadly contents into his home, or “morally responsible” as Mr McCoy candidly put it to the jury[142], he may well have realised the seriousness of his position and chosen to hide behind an investigation of the Mini as the source of the carbon monoxide, rather than imperilling himself and his colleagues and, more particularly, his young family, who would have been without a parent if he had been arrested. His answers to DSgt 16404 did not mean that he was the one who placed the yoga ball in the Mini. 161.Ultimately, even assuming that a right of silence attached to the applicant in May 2015, we think it very unlikely that Mr McCoy, as an experienced tactician, would have preferred the jury to be told that they should not hold the applicant’s failure to assist the investigation into the deaths of his wife and daughter by withholding relevant information against him in any way, rather than be deprived of the applicant’s perhaps ill-judged but nevertheless understandable explanation as to why he did not assist the police in the circumstances; an explanation which may have tied in with the type of person he was. 162.However, as Mr Grounds developed his argument in reply, it appeared to metamorphose into one of intrinsic inadmissibility; either on the basis that the questions and answers were more prejudicial than probative, or because the applicant had a right of silence in May 2015 and, therefore, his lack of assistance to the police about the disappearance of the yoga ball and its toxic contents meant that the evidence should never have been in front of the jury in the first place. While, for the reasons we have already adverted to, we do not think the evidence was more prejudicial than probative, and Mr McCoy made no such submission to that effect, nor did he seek to have the evidence redacted from the first video recorded interview, it is nonetheless necessary to address the argument as to whether the applicant did in fact have a right of silence when spoken to by DSgt 16404 in May 2015. 163.It is common ground that in May 2015, the applicant had not been arrested; he had not been cautioned; he was not even a suspect. If anything, he was a witness who might have been able to assist the police in piecing together what had happened to his wife and daughter. When DSgt 16404 visited the applicant’s home on the night of 22 May 2015 and a few days later, he would have believed he was dealing with a grieving husband and father in respect of a tragedy which, at least on the face of it, neither the applicant nor the police could explain. The applicant’s status at the time he was asked questions in May 2015 is vital to understanding whether he was someone to whom a right of silence attached and, if so, what the right entailed. 164.Mr Grounds submitted that no citizen is obliged to cooperate with, or assist, the police by saying anything when questioned at any stage of an enquiry or investigation. He has a right to remain silent, and that right obtains whether he is a suspect or not. Leaving aside the limited inroads which the legislature has made concerning the obligation on persons in certain circumstances to provide answers to questions posed by an investigating authority, we think Mr Grounds is correct as a matter of law. The point has long been established by the venerable decision of Rice v Connolly[143], where Lord Parker LCJ explained[144]:
165.However, as Lord Parker CJ went on to make clear, the right of silence is exactly that: it is not a right to lie or mislead[145]:
166.In the Scottish case of Boyes v MacLeod[146], presided over by Lord Rodger, the Lord Justice General (later Lord Rodger of Earlsferry SCJ), two accused[147] were passengers in a motor car together with a woman when she was injured by a missile thrown into the car in which they were travelling. Accordingly, the accused drove to a police station to make a complaint and were both interviewed about the incident, without being cautioned. Subsequently, a complaint was made against the accused that before the missile was thrown into their car, they had thrown a missile (or missiles) from their car at a group of pedestrians in the street. The accused objected to the proceedings arising out of that subsequent complaint on the ground that they were oppressive because the accused should have been cautioned in connection with the throwing of missiles from their car at the group of pedestrians. However, they had not been cautioned and had thereby disclosed their defence to the police. On appeal, the Court held[148]:
167.Boyes v MacLeod is an illustration of the point that there is nothing improper in a police officer asking questions of someone who is not a suspect, and who has decided of his own free will to speak. Accordingly, what an un-cautioned non-suspect says to the police in answer to an enquiry is not inadmissible per se. Of course, where it is alleged that the police have tricked someone into believing he was not a suspect so as to obtain information or evidence or an admission from him, when he was in reality a suspect, the information or evidence thus obtained might be objectionable but would depend on the issue, properly engaged in evidence, as to whether that person was a suspect and should have been cautioned. The key is whether or not the person was, at the time of the answer, a suspect, thus warranting his being cautioned. 168.The position of the appellant in the leading authority in this jurisdiction of Lee Fuk Hing v HKSAR [149]was very different. There, the appellant was intercepted while driving a light goods vehicle along a road in the New Territories. As soon as the police revealed who they were, the appellant leapt out of the vehicle and tried to escape. However, he was caught and held by the police. When his vehicle was searched, two bags of heroin were found. He was duly arrested for trafficking in a dangerous drug. At his trial, the appellant gave evidence that the heroin must have been left behind in his vehicle by one Tsang Kei, to whom he had lent his vehicle, and from which he claimed Tsang Kei had alighted shortly before the appellant was intercepted by police. The Judge asked the appellant whether he had ever mentioned the existence of Tsang Kei to the police before and if not, why not. 169.Of these questions, the Court of Final Appeal held[150]:
The Court went on to explain that[151]:
170.It is clear that the Court of Final Appeal was dealing with someone who had been arrested but failed to give an innocent explanation at the time, but which explanation was later relied upon at trial. Indeed, from the moment the appellant jumped out of his vehicle in order to escape, he would no doubt have been suspected of committing a criminal offence. In the case before us, it was not until November 2015 (six months after the conversation between DSgt 16404 and the applicant) that the police made any connection at all between the yoga ball and the deaths of the deceased six months earlier. 171.In his final reply, Mr Grounds produced the further judgment of the Court of Final Appeal in HKSAR v Ata Asaf[152] in support of his contention that everyone, whether suspected of a criminal offence or not, has a right of silence and cannot be criticised for refusing to assist the police in their enquiries. Thus, he contended that even a potential witness has the right to remain silent when asked a question by the police, which cannot later be the subject of any adverse comment. Again, it is important to bear in mind the facts of the case in Ata Asaf and the stage at which comment was made about that appellant’s failure to give an explanation. 172.The appellant had been arrested on a street in Kowloon for the offence of theft and subsequently, upon a search of his person, for the offence of possession of a dangerous drug, after which he was cautioned. Having been cautioned, the appellant declined to say anything. Given the quantity of narcotic concerned, he was later charged with trafficking in the drugs seized from him in the street. The appellant offered to plead guilty to simple possession of the drugs in question, but this offer was refused by the prosecution. At his trial, during cross-examination, prosecuting counsel asked the appellant why, at a subsequent search of his premises following his arrest and caution, he had not mentioned to the police that his alleged drug consuming apparatus for smoking “Ice” had not been pointed out to the officers conducting the search[153]. He responded that he had not been asked by the officer concerned. The Court found that such question and answer were inadmissible. It also held that a further point made in prosecuting counsel’s speech that the appellant had “for the first time” in evidence claimed he had gone to work that morning with $7,000 on his person was improper[154]. 173.In its judgment, the Court held that there were two ways in which a person’s right of silence could be infringed[155]:
The Court went on to note that it was common ground that the offending evidence in the appellant’s premises about his drug-taking equipment was inadmissible[156]:
174.We pause to note the words we have italicised in the above two passages from Ata Asaf and Lee Fuk Hing. They were adopted for good reason. If the right of silence is a privilege against self‑incrimination and is not to become a source of entrapment, then it must attach to those suspected of or charged with a criminal offence in the first place. This mirrors Specimen Direction 45 used in Hong Kong in respect of a defendant’s right of silence:
175.If the right of silence were intended to be applied to anyone who may be connected with an investigation but who is not himself suspected of complicity in the offence, or indeed of any wrong-doing, then we wonder how the ‘caution’ should be framed. It would involve the police officer saying to someone who is not a suspect but who is being asked to help the police with their enquiries as to what has happened, “I would like to ask you some questions. You are not suspected of involvement in this or any other offence, but nevertheless you have the right not to help me with my enquiries”. We suggest this would be an unwarranted, unnecessary and somewhat absurd, development of the common law. Of course, under normal circumstances, a witness can still decline to assist police enquiries without penalty or compulsion. However, if he volunteers information as a witness, before becoming a suspect, we do not see why comment cannot be made about what he has volunteered. Prosecution witnesses are often cross-examined by the defence on the basis of what they said or did not say to the police; and so are defence witnesses, by the prosecution. 176.The fact is, however, that no comment was made by the Judge in this case. All she did was to recite what the appellant had said in his video recorded interview, which leading counsel for the defence actually wanted to go before the jury. Nor was it being suggested by counsel on either side, or by the Judge herself, that the applicant had failed to put forward an innocent explanation when given an opportunity to do so. All he had refrained from doing was helping the police discover that the yoga ball had contained the carbon monoxide which killed his wife and his daughter, a yoga ball which he throughout denied ever placing in the Mini. 177.With respect, we do not see that the statements of principle in Lee Fuk Hing and Ata Asaf have any relevance to the circumstances of the present case. The questions of DSgt 16404, and the answers which they elicited, were not inadmissible; the Judge merely referred to them in the context of her review of the video records of interview without comment; and, in any event, the defence wanted the impugned questions and answers before the jury. As Mr Bruce has correctly pointed out, the applicant was represented by both counsel and solicitor during each of his video recorded interviews and “in the run-up to trial and during the trial by lawyers of the highest calibre”; moreover, “there was never any issue on the voluntariness of taking of the video recorded interviews or their admission as evidence at trial”[157]. 178.In the course of our consideration of this ground of appeal, it seemed to us to be relevant whether or not the applicant had in fact ever declined to assist the police with their enquiries on the night of 22 May 2015 and, again, a few days later. For, if he had chosen to say nothing, or signified his wish not to answer or assist with police enquiries, then at least the factual premise of the applicant’s contended-for right of silence might be established. Without knowing the position, we were in effect being asked to assume an exercise by the applicant of a right of silence in May 2015 when questioned DSgt 16404, which had thus been infringed by the same officer’s questions a year later, when in reality the applicant had never purported to exercise any such right in the first place. We had been informed that Mr McCoy had, for tactical reasons, wished the impugned questions and answers to be included in the video recorded interview which was placed before the jury. It seemed to us relevant to know why counsel might have taken that view, which would depend upon many factors, including his instructions and also, perhaps, the statements or depositions of the officer making the enquiries, which would have shaped the way Mr McCoy dealt with this issue. If, for example, DSgt 16404 had asked questions of the applicant and received answers, at a time when the applicant was not a suspect but was being treated as a witness, the applicant could hardly be said to be availing himself of a right of silence, assuming one even attached to him at that stage. On the other hand, if the applicant said nothing or declined to answer any questions or assist the police, Mr Grounds’ argument that the applicant was entitled to say nothing at that stage, even as a witness, might at least have some foundation. As it was, we were being asked to assume such a foundation, for which the Judge’s subsequent directions amounted to a material irregularity. 179.Accordingly, we wrote to the parties on 28 January 2021 to invite written submissions as to whether the Court could or should look at the statement(s)/deposition(s) of DSgt 16404, which were filed with the trial court at committal in order to better understand the factual and contextual basis for Mr McCoy’s tactical decision. Both parties responded in writing. The respondent had no objection to that course and repeated that there was never any issue as to voluntariness or admissibility of the video recorded interviews: the defence submitted it was not appropriate for the Court to examine the material now, and whether or not the impugned questions and answers were admitted, it was still incumbent on the Judge to inform the jury that the applicant had a right of silence in May 2015. Having considered the respective submissions, we concluded that it was relevant to establish whether or not the applicant had declined to answer questions, from which later questions in interview may have been a derogation of any right of silence; or whether he had answered questions and appeared to cooperate with police enquiries, from which later questions would not be a derogation of any such right. Such information would also have been very relevant to Mr McCoy’s decision as to how to deal with the impugned passages in the video record of interview. 180.DSgt 16404 made two witness statements, one on 1 June 2016, the other on 2 October 2017, both of which were served on the defence in the committal bundle and, therefore, also on the court of trial. There were three sections of the statement of 1 June 2016, which were relevant to the present consideration, namely:
181.The excerpts from the above witness statement, in conjunction with DSgt 16404’s evidence and, in particular, his cross-examination, demonstrate that at no stage of the trial was there any issue whatsoever as to the voluntariness or admissibility of what the applicant told the police qua suspect in his video recorded interviews; nor was there any hint of the applicant purporting to exercise a right of silence qua suspect during the video recorded interviews or, indeed, qua witness during earlier police enquiries. We do not agree with Mr Grounds’ proposition that in order “to ensure a fair trial for the applicant, on the evidence available to the jury, given the emphasis placed on the failure of the applicant to inform the police of his earlier actions, the jury needed to be directed that he was under no obligation to volunteer information to the police and that no adverse inferences should be drawn”[158]. As we have said, no emphasis was in fact placed on this matter by the Judge; but, in any event, there was no duty on her to direct the jury that the applicant had a right of silence qua witness in May 2015 when this was never an issue at trial, and when leading counsel actually wanted all of his answers in the video recorded interviews in May 2016 to go before the jury. When fully analysed, there is no merit in Ground 5. 182.We wish to make clear that we would have arrived at this conclusion even without recourse to the deposition of DSgt 16404. As we have said, we were not prepared to make an assumption, in the absence of any evidence or even suggestion, that the applicant had exercised a right of silence in May 2015 when he was a mere witness as to the unexplained deaths of his wife and daughter. Our examination of DSgt 16404’s statement (which the Judge herself would have seen, since it was among the depositions sent to the High Court) merely reinforces the fact that there never was a right of silence exercised, in respect of a matter about which there was never any issue taken by the applicant’s leading counsel at trial. 183.We now turn to Ground 1 of the Amended Perfected Grounds of Appeal, which concerns pure matters of law, although sub-paragraphs (a) and (b) in fact engage different points of law. Ground 1(a) effectively takes issue with the correctness, as a matter of law, of Specimen Direction 21 in respect of circumstantial evidence, since it is said to impose a similar burden and standard of proof on the defence to provide “good evidence”[159], or evidence “of sufficient reliability and strength to cast doubt upon or destroy the prosecution case”[160]. A further complaint concerns the direction given at the outset of her summing-up, which is taken from Specimen Direction 1 dealing with the respective functions of the Judge and the jury, that the jury were to form their “own judgment about the witnesses on which evidence is reliable and which is not”[161]. It is said that this was also a misdirection; for it gave rise to the risk of the jury rejecting defence evidence which might be true. 184.In making this argument, Mr Grounds faced an obvious hurdle, inasmuch as the directions about which he complained are in fact standard Specimen Directions, which have been approved by the Hong Kong Judicial Institute and applied in countless cases where the directions on circumstantial evidence are required for very many years. Nonetheless, Mr Grounds is entitled to take the point and we have examined it carefully to see whether the criticisms of the relevant Specimen Directions are valid. 185.We may deal first with the complaint about that part of Specimen Direction 1 which directs the jury to make their own judgment about the reliability of the evidence of witnesses. With respect, the context of Specimen Direction 1 is the opening direction of a summing-up concerning the respective functions of the Judge and the jury. It tells the jury that they must look at all the evidence in order to determine what evidence they are going to rely upon in deciding whether the charge laid against the defendant has been proved. The argument that the jury might from this general direction reject unreliable evidence that may in fact be true is specious semantics, which ignores the other later directions that are routinely given to juries, and were given to the jury in this case: that the jury had to be sure of guilt beyond a reasonable doubt[162]; that if there was a reasonable doubt arising from the defence case put forward, which included his own account in interview and the evidence of witnesses, he must be found not guilty[163]; and that even if the defence case were to be rejected, the jury still had to be sure that the prosecution had established the guilt of the defendant[164]. 186.The direction on circumstantial evidence, about which complaint is then made, has been approved by the Hong Kong Judicial Institute and is derived from same direction endorsed by the Judicial Studies Board used in England and Wales. In R v P[165], Thomas LJ (later Lord Thomas CJ), giving the judgment of the Court of Appeal of England and Wales, held:
187.The direction approved by Thomas LJ is virtually indistinguishable from the direction given by the Judge in this case, which is itself taken verbatim from Specimen Direction 21 approved for use by the Hong Kong Judicial Institute. With respect to Mr Grounds’ argument, it does not make sense to talk of circumstantial evidence being “truthful” as distinct from “reliable”, since circumstances are, by their very nature, indirect or objective conditions or external events, which are not usually dependant on their internal veracity or the truthfulness of a witness’s testimony. The question will normally be whether such circumstantial evidence can be relied upon in proof of guilt and whether it does in fact prove guilt; or whether, on the other hand, it undermines the prosecution case. And when the Specimen Direction speaks of such evidence revealing any other circumstances, which are or may be of sufficient reliability and strength to cast doubt upon the prosecution case, it is applying the concept of reasonable doubt to circumstantial evidence. We do not agree that the Judge’s directions wrongly assimilated the prosecution and defence standards of proof. On the contrary, they emphasise the importance and necessity for the jury to consider whether such evidence does in fact prove guilt. 188.There is no merit in this ground of appeal. The directions on the expert evidence 189.We will deal with the complaints about the Judge’s failure to summarise the defence case and the expert evidence together as they overlap considerably and seek mainly to reargue or argue afresh scientific and technical issues in answer to the allegations against the applicant. 190.The essence of the applicant’s submission is that the Judge failed to properly summarise the expert evidence and hence did not fully present the defence case to the jury[166]. It is generally complained by the applicant that the Judge failed adequately to summarise the expert evidence, “doing so variously in insufficient or excessive detail, without proper balance and with various errors.” The specifics of this ground are contained in the grounds in respect of the applicant’s research and the timeline defence. It is argued that the Judge wrongly directed the jury that they had to choose between the conflicting evidence of the experts[167] and did not properly address the defence expert evidence in respect of the timeline defence (the dissipation rate of carbon monoxide)[168] and the genuineness of the applicant’s research[169]. 191.Of the failure to summarise the defence case, the applicant further complained about the Judge’s summary of evidence in relation to the reinjection of blood into the rabbits[170]; and the issue of when the stopper of the yoga ball went missing[171]. 192.The Judge, having reminded the jury in some detail that it was their responsibility to Judge the evidence, went on to tell them to consider the closing speeches of counsel and whatever they thought was important in the evidence, even though she may not herself have mentioned it[172]:
193.It is complained that the Judge told the jury they had to choose between the conflicting evidence of the experts, and therefore excluded the possibility of them not reaching a firm conclusion on the relevant issue(s)[173]. In our view, the Judge did not give any such direction. She very carefully, and correctly, explained how the jury should approach the expert evidence without limiting how they were to consider it but noting that there were conflicting views between the experts which they had to consider. She said[174]:
194.We observe that the Judge by her remarks above followed Specimen Direction 32 in respect of expert evidence. It is important to bear in mind that in the context of a criminal trial, experts do not decide cases, juries do. Expert evidence is admitted only in respect of matters that lie beyond the common experience and knowledge of the jury, and in order to assist them to understand scientific and complex facts at issue during the trial: R v Turner[175]. Often experts will differ in their opinions and it is for the jury to decide between the experts, by reference to all the available evidence and what is in issue: R v Kai-Whitewind[176]; R v Brennan[177]. 195.The Judge presented to the jury a very comprehensive summary of the expert evidence, noting the issues which the experts sought to address as well as the issues that arose between them. When appropriate and relevant, she dealt with the expert evidence in the context of the evidence of the witnesses and related exhibits. 196.It might be stating the obvious, but a summing-up is not meant to be a full recitation of all the evidence, nor a complete delineation of all the issues. It is to provide a clear and precise overview of the salient facts and circumstances of the case, as well as addressing the main issues and matters that warrant consideration by the jury, with appropriate directions or guidance as the law requires in determining the count or counts on which they are to return a verdict. 197.The expert evidence at trial focused primarily on two issues. The first was the applicant’s research in respect of carbon monoxide poisoning and whether it was a genuine research project. The second was the leakage rate of carbon monoxide from the Mini and the deflation rate of carbon monoxide from the yoga ball, which was relevant to the timeline defence. These two issues were crystallised for the jury by the Judge’s early remarks to them[178]:
198.The Judge then explained how she would address the expert evidence in respect of the two issues between the parties. She said[179]:
199.She went on to explain to the jury that the expert evidence was before them[180]:
200.Mr Grounds complained that the Judge failed to remind the jury of the defence case that the applicant’s research was genuine for a myriad of reasons that mainly consist of comment or submission on the case for and against the genuineness of the applicant’s research[181]. Some of these points were made by leading counsel for the applicant in his closing speech to the jury[182], while others are new and selective. The Judge in her summing-up emphasised the respective cases advanced by the prosecution and defence at trial[183]. The jury had the benefit of seeing and hearing the witnesses and receiving detailed closing speeches from the parties. They would have been well aware of the arguments on the issue of the genuineness of the applicant’s research. As a result of the numerous criticisms that have been made on this subject by the applicant, we need to address them by extensive reference to the evidence, the arguments at trial and the summing-up. 201.We will begin our consideration of the applicant’s research by quoting the Judge’s summary of the evidence of the applicant’s initial discussions with Professor Qin concerning his proposed study and the arrangements that followed[184]:
202.The Judge went on to deal with the study protocols for the research[185]:
203.The Judge next addressed the evidence in respect of the two experiments on 13 and 20 May 2015[186]:
204.The Judge addressed at length the separate issue of whether the applicant’s research was a sham. This was the main focus of the applicant’s complaint about the Judge’s treatment of the expert evidence. It is therefore necessary that we set it out in full. One of the criticisms of the Judge’s summing-up was that she did not address the defence case in respect of the “extra haemoglobin effect”. As revealed from the following passages, she did in fact deal with this issue and appropriately reminded the jury about it[187]:
205.The Judge continued to summarise the evidence and the issues in relation to the applicant’s research[188]:
206.At this point of her summing-up on the subject of the applicant’s research, the Judge turned to address the issue of reinjection of the blood into the rabbits[189]:
207.The Judge, at the conclusion of her summing-up, reminded the jury of the defence case that the applicant’s research was not a sham. She said[190]:
208.Mr Grounds complained that the Judge was selective in her overview of Professor Joynt’s evidence[191]. He noted that the Judge only mentioned that the protocols outlining the applicant’s research had not been submitted to the University’s Ethics Committee; that the protocols were too rudimentary and had they been submitted to him, he would have sent them back; and that he saw no direct link between carbon monoxide poisoning and the applicant’s particular speciality. 209.Mr Grounds submitted that the Judge failed to mention Professor Joynt’s evidence that reperfusion injury, the inflammatory response which occurs when oxygen is restored to tissue after hypoxia, could in theory be reduced by treatment with less than 100% oxygen and that at some time in the future it might be shown that administering 100% oxygen may not be the safest way of treating a patient with carbon monoxide poisoning. 210.Professor Joynt’s references to reperfusion injury and treating a patient for carbon monoxide poisoning with 100% oxygen arose in the context of his general criticisms of the applicant’s proposed research, including the procedure of injecting an experimental animal with carbon monoxide, rather than breathing it in. He was particularly critical, and this was the focus of his evidence, of the rudimentary nature of the applicant’s proposed research and his failure to follow the strict procedures for approval of a research project of this kind. Leading counsel for the applicant did not mention these matters in his closing address, nor did he complain about the Judge’s overview of the expert evidence relating to the applicant’s research in her summing-up. As already noted in the quoted passages of the Judge’s summing-up, she did provide a summary of the expert evidence in respect of the use of 100% oxygen for patients suffering from carbon monoxide poisoning[192]. 211.As pointed out by the respondent, the Judge gave a very comprehensive account of the competing evidence concerning the applicant’s proposed research. 212.A key aspect of the prosecution case as to the genuineness of the applicant’s research was that the applicant had not submitted his research proposal to Professor Joynt. He testified that the applicant had not followed the procedures required; moreover, he was critical of the nature of the research proposal the applicant had produced[193]. It was also the case that the applicant’s expert, Professor Buckley, a clinical pharmacologist and toxicologist, expressed his disapproval of the form of the proposal submitted by the applicant[194]. 213.As explained by the respondent, the Judge directed the jury that there was a disagreement between the prosecution and the defence on the issue of “extra haemoglobin effect”. She quoted Professor Buckley who testified that he did not subscribe to it because it had not been proven. 214.Mr Grounds complained about the Judge’s comments as to whether or not blood was reinjected into the rabbits. It is contended that if reinjection took place it gave greater legitimacy to the applicant’s experiments. 215.Mr Grounds submitted that leading counsel for the applicant argued that the carbon monoxide oximeter readings for the two experiments revealed a percentage increase that was followed by a decrease of the carboxyhaemoglobin, which in the opinion of Professor Wang showed that the blood had been reinjected into the rabbits. 216.We will also need to address this ground in some detail to show the point made by Mr Grounds about reinjection was unsupported at trial and unsustainable upon appeal. 217.Mr Bruce addressed the jury on the genuineness of the applicant’s research and the issue of reinjection as follows[195]:
218.In his closing speech, Mr McCoy addressed the issue of the genuineness of the applicant’s research and focused on Professor Wang’s evidence that the carbon monoxide oximeter readings showed the blood had been reinjected[196]:
219.Dr Dick Chow testified about the procedures adopted in the two experiments on 13 and 20 May 2015. He said that the applicant had obtained a quotation for the purchase of carbon monoxide on 10 June 2014. This was well before the applicant had suggested the proposed research to anyone. He later purchased the carbon monoxide initially arranged by the applicant for the experiments in May 2015[197]. He referred to the procedure for the experiments as set out in a document entitled ‘Short-Term Experimentation’ under section D of the form[198]. 220.He said the experiment on 13 May involved one rabbit, but there was some difficulty getting the blood out of the animal and saturating the blood with carbon monoxide. Eventually they were only able to extract 10 millilitres of blood (instead of 20 ml) and settled on a method of saturating the blood with carbon monoxide by putting the gas directly into the syringe containing the blood. They then tested the blood concentration of the carbon monoxide using the oximeter. The experiment ended at that point[199]. 221.The experiment on 20 May also involved one rabbit. They followed the same procedure as before and only extracted 10 millilitres of blood “because again this is a rehearsal or trial, so we didn’t -- it’s not actually performing the actual experiment, so we are still testing out the protocol.”[200] He further explained[201]:
222.In cross-examination, Dr Dick Chow was not challenged at all in respect of the procedures adopted for the two experiments; or that no reinjection took place on those two occasions[202]. 223.Ms Tam was the laboratory assistant involved in the experiments who was responsible for the carbon monoxide oximeter analysis. Her evidence was read out pursuant to section 65B of the Criminal Procedure Ordinance, Cap 221. Insofar as is material, she stated that at the beginning of the experiment on 13 May, the applicant and Dr Dick Chow let the rabbit inhale carbon monoxide and drew the blood from the rabbit. The blood sample was passed to her and her colleague for analysis by the carbon monoxide oximeter. This procedure was conducted repeatedly and the result was printed by the carbon monoxide oximeter for each analysis. 224.On 20 May, the procedure of the experiment was similar to the previous one. The applicant and Dr Dick Chow let the rabbit inhale carbon monoxide and drew blood from the rabbit. She received the blood sample for analysis by the CO oximeter and handed the results to the applicant. She did not mention that there had been reinjection of the blood back in the rabbit[203]. 225.Ms Tam’s evidence was slightly at variance with that of Dr Dick Chow as to how the carbon monoxide was infused into the blood, but they were both consistent in making no mention of reinjection having taken place. 226.Professor Wang’s opinion that reinjection took place in both experiments was solely based on his interpretation of the CO oximeter readings, although he seemed also to have been influenced by what he had been told by the applicant. His evidence on this issue was as follows[204]:
227.The term ‘timeline defence’ was a description used on appeal but was not one used at trial[205]. One of the many suggestions made by the defence was the timeframe in which the applicant had an opportunity to place the yoga ball in the boot of the Mini and remove its stopper, and the timeframe for the level of carbon monoxide in the Mini to result in the death of Madam Wong and Lily by the time and at the location where the vehicle was found. This submission, to the extent it was made at trial, was in very general terms and with various qualifications because of the inexact nature of the evidence. 228.It is argued by Mr Grounds that the defence case in relation to the carbon monoxide concentration was that for Madam Wong to have been overcome so soon after departing from her home, the yoga ball must have been placed in the car shortly before she set off, which would rule out the applicant as the person responsible for putting the yoga ball in the car. 229.Mr Grounds pointed to Mr McCoy’s closing speech to the jury when this defence was explained to them. In order to evaluate the argument being advanced by Mr Grounds, it is necessary to refer to the actual comments of leading counsel, on which he relies. It will be recalled that Madam Wong and Lily got into the car at about 2:00 pm and Madam Wong then drove the car for a distance of about 1.6 kilometres when she and Lily were overcome by the carbon monoxide released from the yoga ball. Mr McCoy stated[206]:
230.Later in his closing speech[207], Mr McCoy returned to this issue:
231.It can be seen from leading counsel’s speech on this point that it was heavily qualified, and not in the concrete terms in which it is now presented before us. As will become apparent, counsel on appeal are, to a significant extent, arguing a completely new and different case. 232.It is complained that the Judge did not remind the jury of the defence case in respect of the timeline argument, and without giving guidance to the jury as to the conclusions open to them from Dr Wong’s tables as to concentration levels, nor from the tables of Dr Foo and Professor Kwong as to the consequences of different levels of exposure; and without properly reminding the jury of Professor Li’s experiments and his criticisms of Dr Wong’s evidence. 233.The argument presented in respect of the timeline defence vacillated between accepting Dr Wong’s evidence at its highest and rejecting his evidence because it was unreliable or inaccurate. It is complained that the jury should have been directed to ignore the results of Dr Wong’s experiment as to fresh air being drawn into the car by assuming that the car engine was on and that the ventilation was set on recirculation. As leading counsel for the applicant pointed out in his closing address, there were a number of variables and unknowns in relation to what were the exact circumstances at the relevant time or times[208]. The Judge gave a lengthy and comprehensive overview of the expert evidence, particularly the evidence of Dr Wong and Professor Li. In our view, the criticisms levelled at the Judge in this regard are unfounded, and amount to a selective view and novel analysis of the expert evidence. 234.It was accepted by Mr Grounds that the Judge dealt at great length with Dr Wong’s and Professor Li’s evidence but complaint was still made that the jury was left without proper guidance as to the implications of Dr Wong’s tables and the carbon monoxide exposure tables. These tables were all before the jury and the Judge did direct them to use the tables as appropriate to see the effect that could be expected from the concentration levels of carbon monoxide[209]. 235.Mr Grounds has carried out a detailed analysis of the carbon monoxide level in the car over a time period, which ignores, as was appreciated at trial, that such analysis was subject to a number of variables and unknowns. 236.The relevant passage of the Judge’s summing-up on the timeline defence was extremely comprehensive and addressed the relevant issues raised by the parties[210].
237.Having dealt with the expert evidence and related issues, the Judge went on to deal with the question of who put the yoga ball in the boot of the Mini, and when it could have been done. She noted that there was no evidence as to when the yoga ball was actually placed inside the boot, and then took the jury through relevant factual matters for them to consider[211].
238.There is no justification in the criticisms of the Judge’s lengthy outline of the evidence of Dr Wong and Professor Li. She specifically mentioned the two tests that had been carried out by Dr Wong and the differences between them, as well as the various factors and circumstances that had to be taken into account when considering this evidence. She suggested to the jury that they use Dr Wong’s tables to consider when the yoga ball would have been placed in the car, noting that the opening and closing of the car doors would have caused a “huge drop” in the concentration of carbon monoxide present and that the period of time the doors of the car remained open was important because of the possible dissipation of gas[212]. 239.In contrast, Mr Grounds submitted that the Judge should have directed the jury to ignore Dr Wong’s test results of gas concentration in the car, although at times he relied on them in his arguments. 240.The fact is the evidence in respect of the gas concentration and dissipation was before the jury and the Judge comprehensively summarised that evidence and appropriately identified the issues that had been raised by the parties. The Judge also reminded the jury of the timeframe and opportunity for the applicant to have placed the yoga ball in the car. It has to be remembered that the evidence concerning the gas concentration and dissipation of carbon monoxide in the car was subject to a number of variables and qualifications and was part of a matrix of evidence that the jury were asked to consider. As noted by Mr Bruce, the undisputed evidence was that Madam Wong with Lily got into the car and managed to drive for a distance of 1.6 kilometres before she lost consciousness, both exhibiting high levels of carbon monoxide in their blood. The missing stopper 241.It is complained that the Judge misdirected the jury as to whether the stopper was missing on 22 May 2015. The applicant made three points. First, the Judge did not appropriately address the possible errors and unreliability of the exhibits officer as well as the possibility that he may have been mistaken when he stated that he had not found the stopper. Secondly, the Judge omitted to direct the jury as to the possibility that the stopper had been mishandled or misplaced in the six months which had elapsed before the exhibits officer searched the Mini. Thirdly, the Judge erred in directing that if the jury were sure the exhibits officer had been truthful then Lily could be ruled out as the person who had put the yoga ball in the Mini as she had no reason to throw the stopper away. It is contended the same direction should have been given in respect of the applicant. 242.The last point complained that the Judge failed to direct the jury that if there was no stopper there was no reason for the applicant to throw it away. This presupposed the applicant put the yoga ball in the boot of the Mini and removed the stopper. This argument was contrary to the defence case at trial. If the applicant had done so, then it would have supported the prosecution case against him that he put the yoga ball in the car and intentionally released the carbon monoxide. In such circumstances, it would be argued that he threw away the stopper so as to draw attention away from the yoga ball as the source of the carbon monoxide. Sensibly, leading counsel did not make a point of this before the jury, although it does highlight the problem when a new team of lawyers take on a case on appeal and with creative fervour come up with a point which was not run at trial. As to the body of the complaint under this ground, there is no substance in it. The Judge reminded the jury of the very things that the applicant has complained she did not do. She reminded them of the defence case and told them that they should consider the evidence of the exhibits officer and whether his account of not finding the stopper to the yoga ball was reliable. She also mentioned the matter of the exhibits officer mixing up the exhibit numbers and other items[213]. 243.At the conclusion of her summing-up, the Judge gave a comprehensive overview of the defence case, including the defence argument about the missing stopper. She said[214]:
244.It is plainly apparent that the judge did address the issue of the missing stopper detailing the evidence and emphasising the defence submissions on the matter. 245.In the course of this lengthy judgment, we have seen fit to recite extensive passages from the summing-up. We have done this not only to show how many of the grounds are fully answered in the Judge’s summing-up itself, but also to demonstrate, with respect, how thorough and meticulous the Judge was in addressing the myriad of issues which were raised at trial. 246.It follows from our detailed consideration of the evidence and the multitude of the grounds of appeal advanced that in our judgment the applicant had a thoroughly fair trial; moreover, there was cogent and compelling evidence to justify his convictions on both counts of murder. His application for leave to appeal against conviction is refused and his appeal accordingly dismissed.
Mr Andrew Bruce SC, counsel on fiat, and Ms Christal Chan, ADPP (Ag), of the Department of Justice, for the Respondent Mr Christopher Grounds, Mr Andrew Bullett and Mr Franco Kuan, instructed by CL & Co Solicitors, for the Applicant [1] Appeal Bundle, pp A60H-O and 61N-68K. [2] Appeal Bundle, p A70N-O. [3] Appeal Bundle, p C479N. [4] Appeal Bundle, pp C479T-480A. [5] Appeal Bundle, p C479T. [6] Appeal Bundle, p C480H-L. [7] Appeal Bundle, p 31, at [47]-[48]. [8] Appeal Bundle, p A140P-V. [9] Appeal Bundle, p A33. [10] Appeal Bundle, p A93A-C. [11] Appeal Bundle, p A93K-M. [12] Appeal Bundle, pp A92T-94F. [13] Appeal Bundle, p A95A-P. [14] Appeal Bundle, p A116O-R. [15] Appeal Bundle, pp A90C-92N. [16] Appeal Bundle, p A113G-I. [17] Appeal Bundle, p A113. [18] Appeal Bundle, pp A146S-147A-E. [19] Appeal Bundle, p A147E-F. [20] Appeal Bundle, p A147I-L. [21] Appeal Bundle, p 147Q-U. [22] Appeal Bundle, p A148M-P. [23] Appeal Bundle, p A149A-I. [24] May May; Ms Sarah Niu, a classmate in Renaissance College; Ms Eunice Li Lok Ting, a school friend; Ms Lesley Ann Harrison and Mr Trevor John Newman, teachers from Renaissance College; Ms Foong and Dr Cheong, family friends; and Madam Chen Li, a neighbour. [25] Appeal Bundle, p A151J-L. [26] Appeal Bundle, p A151S. [27] Appeal Bundle, pp A152P-153D. [28] Appeal Bundle, p A157N-Q. [29] Appeal Bundle, p A85K-L. [30] Appeal Bundle, p A153H-M. [31] Appeal Bundle, p A153M-O. [32] In addition to these witnesses, the prosecution also relied on the evidence of Professor Qin Ling (PW8), Dr Dick Chow and Ms Tam Tsui Ping (PW23). [33] The time taken for a body to get half of the carbon monoxide out of the body. [34] Appeal Bundle, p A168I-N. [35] Appeal Bundle, p A167H-L. [36] Appeal Bundle, p A172Q-T. [37] Appeal Bundle, p A169B-G. [38] Appeal Bundle, p A169N-O. [39] Appeal Bundle, p A170A-E. [40] Appeal Bundle, p B727. [41] Appeal Bundle, p B715C-G. [42] Appeal Bundle, p A169S-U. [43] Appeal Bundle, p B722M-R. [44] Appeal Bundle, pp B714N-715A. [45] Appeal Bundle, p A160Q-T. [46] Appeal Bundle, pp A161U-A162B. [47] Appeal Bundle, p A172L-N. [48] Appeal Bundle, p A171Q-S. [49] Appeal Bundle, p A171R-T. [50] Appeal Bundle, pp 507R-508D. [51] Appeal Bundle, p 537G-M. [52] Appeal Bundle, pp C544-547. Ms Tam’s witness statement was admitted into evidence pursuant to section 65B of the Criminal Procedure Ordinance, Cap 221. She stated that on each occasion they let the rabbit inhale carbon monoxide and drew its blood. She made no reference that the blood was infused back into the rabbit. [53] Appeal Bundle, pp A163-164 and A75S-U and A76L-N. [54] Appeal Bundle, p A75P-R. [55] Appeal Bundle, A172M-O. [56] Appeal Bundle, p C209. [57] Appeal Bundle, p A155E-J. [58] Appeal Bundle, p A77E-G. [59] Appeal Bundle, p A68N. [60] Appeal Bundle, pp A54P-R and B538L. [61] Appeal Bundle, p A117E-F. [62] Appeal Bundle, p A155P-U. [63] Appeal Bundle, p A156A-E. [64] Appeal Bundle, p A156K-L. [65] Appeal Bundle, p A157B-C. [66] Appeal Bundle, p A157H-M. [67] Appeal Bundle, p A69B-C. [68] Appeal Bundle, p A179D-E. [69] Appeal Bundle, p A179J-L. [70] Appeal Bundle, p A176S-T. [71] Appeal Bundle, p A177A-D. [72] Exhibit D1. [73] Appeal Bundle, p A203N-U. [74] Appeal Bundle, p A204J-L. [75] There was no issue with the mechanics of the car and it was an admitted fact the carbon monoxide did not come from the car: see Admitted Facts, at [15], Appeal Bundle, p A19. [76] This test was done over the course of 5 hours, using the Mini and a yoga ball filled ¾ full with carbon monoxide. Another test was done on March 17, 2017, but when Dr Wong opened the door after 3 hours he found the yoga ball had burst. [77] Appeal Bundle, p A194M-P. [78] Appeal Bundle, p A188S-T. [79] Appeal Bundle, p A110E-F. [80] Appeal Bundle, p A197F-H. [81] Appeal Bundle, p A190Q-T. [82] Appeal Bundle, p A197J-Q. [83] See Admitted Facts, at [49], at Appeal Bundle, p A32. [84] See Admitted Facts, at [50], at Appeal Bundle, p A32. [85] Appeal Bundle, p A198D-F. [86] Appeal Bundle, p A198F-I. [87] Amended Perfected Grounds of Appeal Against Conviction filed on 23 January, 2020, signed by Mr Christopher Grounds and Mr Andrew Bullett. [88] Appeal Bundle, pp A127N-A129M, A133D-H, A136E and A137I-T. [89] Appeal Bundle, p A129A-I. [90] Appeal Bundle, p A130B-C, M-Q, and T. [91] Appeal Bundle, p A128A-I. [92] Appeal Bundle, pp A196C-206H. [93] Appeal Bundle, pp A158T-176A. [94] Appeal Bundle, pp A124L, A145L-O, and A205N-206B. [95] Appeal Bundle, p A205I-M. [96] Ground 11. [97] Appeal Bundle, p A143I. [98] Appeal Bundle, pp A125D-H, 143I-J and 208A-211T. [99] Appeal Bundle, p A114S-T. [100] Appeal Bundle, p A113H-I. [101] R v Henderson and Others [2010] 2 Cr App 24. [102] Appeal Bundle, pp A178J-179K. [103] Appeal Bundle, pp A124S-125C and A202B-204O. [104] Appeal Bundle, pp A202B-206P. [105] Appeal Bundle, p A152C-K. [106] Appeal Bundle, pp A177B-178N. [107] Appeal Bundle, pp A131T-135P. [108] Appeal Bundle, p A133M-Q. [109] Applicant’s Reply, dated 30 November 2020, at para 4. [110] Applicant’s Reply, dated 30 November 2020, at para 5. [111] There were two keys to the Mini. Exhibit 2 was the key found in the Mini at the time of the deaths, Exhibit 11 was the key recovered by DSgt 16404 in the house on 13 July 2015, which was handed over to the exhibits officer. See Appeal Bundle, pp C571F-C572C and C573T-C574E. [112] Appeal Bundle, p A107R-S. [113] Appeal Bundle, pp A16-A17, at [6]-[9]. [114] Appeal Bundle, p A205A-M. [115] Appeal Bundle, p A205I-M. [116] Appeal Bundle, p A160B-L. [117] Appeal Bundle, pp A125T-A126E. [118] HKSAR v Apelete (No 1) [2019] 5 HKLRD 574, at [69]. [119] HKSAR v Abedin Minhajaul [2022] 2 HKC 205. [120] HKSAR v Chung Chun Fung and Another (Unrep., CACC 28/2020, 3 December 2021), at [35] and [36]. [121] Roach v The Queen (2019) 344 FLR 429, at para 195. [122] Written Submissions of the Applicant, at [14]. [123] Appeal Bundle, pp C153-C154, at entries 2312-2322. [124] Appeal Bundle, pp C154-C156, at entries 2328-2348. [125] Appeal Bundle, p A91S-U. [126] Appeal Bundle, p A154J-K. [127] Appeal Bundle, at [6]. [128] Appeal Bundle, p A157C-M. [129] Appeal Bundle, p A95R; p A103G. [130] Appeal Bundle, p A96A. [131] Appeal Bundle, p A95T. [132] Appeal Bundle, pp A95U-A96A. [133] Appeal Bundle, p A103G. [134] Appeal Bundle, p A103H; p A103P. [135] Appeal Bundle, p A103P. [136] Appeal Bundle, p A103I. [137] Appeal Bundle, p A103K; p A114T. [138] Appeal Bundle, p A103R. [139] Appeal Bundle, p A103J. [140] Appeal Bundle, p A103T; p A104H; p A104J. [141] Appeal Bundle, p A103L. [142] Appeal Bundle, p A114S-U. [143] Rice v Connolly [1966] 2 QB 414. [144] Ibid., p 419E-F. [145] Ibid., p 420A-B. [146] Boyes v MacLeod 1997 SLT 1348. [147] The two accused were brothers with the surname Boyes. [148] Ibid., p 1349B-E. [149] Lee Fuk Hing v HKSAR (2004) 7 HKCFAR 600. [150] Ibid., at [55]. [151] Ibid., at [56]. [152] HKSAR v Ata Asaf (2016) 19 HKCFAR 225. [153] In evidence, the appellant said that the apparatus was outside the window under an air-conditioning unit. [154] Ibid., at [28] and [29]. [155] Ibid., at [10] and [11]. [156] Ibid., at [12]. [157] Respondent’s further written submissions, dated 10 February 2021, at [4]. [158] Reply to letter dated 28 January 2021 from Macrae VP, dated 10 February 2021, at [8]. [159] Appeal Bundle, p A133T. [160] Appeal Bundle, p A133P-Q. [161] Appeal Bundle, p A126D. [162] Appeal Bundle, pp A128L-Q; p A129M. [163] Appeal Bundle, p A129F-H. [164] Appeal Bundle, p A129K-M. [165] R v P [2008] 2 Cr App R 6. [166] Ground 5. [167] Ground 2. [168] Ground 6 and Ground 17(a), (b), (c)(i), (ii) and (iii), (d) and (e). [169] Ground 7(a) and (b) and Ground 16(a), (b), (c), (d), (e) and (f)(i) and (ii). [170] Ground 8. [171] Ground 11(a), (b), and (c). [172] Appeal Bundle, pp A127O-128I. [173] Ground 2(a). [174] Appeal Bundle, p A160C-N. [175] R v Turner [1975] QB 834, at 841. [176] R v Kai-Whitewind [2005] EWCA Crim 1092, at [89]. [177] R v Brennan [2014] EWCA Crim 2387, at [44]. [178] Appeal Bundle, p A125C-N. [179] Appeal Bundle, pp A158T-159M. [180] Appeal Bundle, pp A159Q-160C. [181] See para VIII of the Amended Perfected Grounds of Appeal, which is set out in para 124 of this Judgment. [182] Appeal Bundle, pp A96D-100C. [183] Appeal Bundle, pp A165N-175S. [184] Appeal Bundle, pp A160P-162B. [185] Appeal Bundle, p A162C-P. [186] Appeal Bundle, pp A162Q-165N. [187] Appeal Bundle, pp A165O-166Q. [188] Appeal Bundle, pp A166R-173N. [189] Appeal Bundle, pp A173O-175S. [190] Appeal Bundle, pp A205N-206B [191] This addresses Ground 8. [192] Appeal Bundle, pp A166R-168H. [193] Appeal Bundle, p A162H-M. [194] Appeal Bundle, pp A171R-178A. [195] Appeal Bundle, pp A66I-67Q. [196] Appeal Bundle, pp A96M-97L. [197] Appeal Bundle, pp C509R-511M. [198] Appeal Bundle, pp C542-543, Exhibit 124E. [199] Appeal Bundle, pp C522K-526O. [200] Appeal Bundle, p C530D-E. [201] Appeal Bundle, pp C530T-531F. [202] Appeal Bundle, pp C536F-540B. [203] Appeal Bundle, pp C545-546, at [5] and [6]. [204] Appeal Bundle, p B725H-L. [205] This addresses Ground 7. [206] Appeal Bundle, pp A104M-105T. [207] Appeal Bundle, pp A111B-112K. [208] Ibid. See the italicised passages. [209] Appeal Bundle, pp A198J-P and 200B-J. [210] Appeal Bundle, pp A179T-194P. [211] Appeal Bundle, p A198C-S. [212] Appeal Bundle, p A198Q-T. [213] Appeal Bundle, pp A204P-205N. [214] Appeal Bundle, pp A203O-204T. |
Cases cited in this judgment
Other judgments that cite this case
Further hearings and rulings under CACC 309/2018