HKSAR v. Khaw Kim Sun (許金山)

Press Summary (English)

Press Summary (Chinese)

FACC NO. 8 OF 2023

[2023] HKCFA 37

IN THE COURT OF FINAL APPEAL OF THE

HONG KONG SPECIAL ADMINISTRATIVE REGION

FINAL APPEAL NO. 8 OF 2023 (CRIMINAL)

(ON APPEAL FROM CACC NO. 309 OF 2018)

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JUDGMENT

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Chief Justice Cheung:

1.I agree with the joint judgment of Mr Justice Fok PJ and Mr Justice Lam PJ.

Mr Justice Ribeiro PJ:

2.I agree with the joint judgment of Mr Justice Fok PJ and Mr Justice Lam PJ.

Mr Justice Fok PJ and Mr Justice Lam PJ:

3.On 19 September 2018, the appellant was convicted after trial, before Barnes J and a jury,[1] of two counts of murder. The victims were the appellant’s wife, Madam Wong Siew Fing (“Madam Wong”), and daughter, Khaw Li Ling (“Lily”), and they had been poisoned by carbon monoxide issuing from a yoga ball placed in the car in which they were travelling. The jury’s verdicts on the two counts were unanimous and the appellant was sentenced by the Judge to life imprisonment on each count.

4.The appellant’s application for leave to appeal was unanimously dismissed by the Court of Appeal on 7 June 2022.[2] On 25 October 2022, the Court of Appeal refused to certify two points of law for which the appellant sought a certificate in order to pursue an appeal to this Court.[3]

5.On 6 June 2023, the Appeal Committee granted leave to appeal to the Court of Final Appeal limited to the basis that it was reasonably arguable that the Judge’s directions to the jury concerning inferences that might be drawn from the allegedly missing stopper of the yoga ball amounted to a misdirection and gave rise to substantial and grave injustice.[4]

The prosecution case

6.The prosecution case was based on circumstantial evidence which was to the following effect. In the afternoon of 22 May 2015, Madam Wong, aged 47, and Lily, aged 16, were found unconscious in Madam Wong’s yellow Mini Cooper car which was stationary at a bus stop near Sai O Village in the New Territories and about 1.6 km from the house in Tai Tung Village in which they lived. Madam Wong and Lily were removed from the car by paramedics and taken to Prince of Wales Hospital, where they were both certified dead. The cause of death was carbon monoxide poisoning and the time of their deaths was estimated at between 12.45 pm and 2.45 pm on 22 May 2015. Initial investigations focused on the car as the source of the carbon monoxide gas. The car, however, was not the source of the gas. Instead, the carbon monoxide had escaped from a yoga ball that was found partially deflated in the boot of the car when Madam Wong and Lily were discovered. The yoga ball in question, together with another yoga ball, had been filled with carbon monoxide by the appellant, in the circumstances described further below. The critical questions at the trial were who put the yoga ball in the car and why.

7.The appellant was, at the time, an Associate Professor in the Department of Anaesthesia and Intensive Care at the Chinese University of Hong Kong (“CUHK”) and a Senior Medical Officer at the Prince of Wales Hospital. Although he was still married to Madam Wong and living in the same house as her, the couple were in effect living separate lives and, to Madam Wong’s knowledge, the appellant was in an intimate relationship with a colleague at CUHK, Ms Shara Lee, who had been a former student. Also living in the same house were three of the couple’s four children, namely Lily and her two younger siblings, Carly and Didi, and their live-in domestic helper, Siti. When the appellant was initially interviewed by the police in May 2015, the appellant, not then a suspect, did not mention the yoga ball and the carbon monoxide in it. It was only in about November 2015 that the police realised that the source of the carbon monoxide was the yoga ball and started to focus their investigation on how it came to be in the car. In May 2016, about a year after the deaths, the appellant, by then under caution, made voluntary statements in video recorded interviews including statements concerning the yoga ball and its contents.

8.The circumstances in which the yoga ball came to be filled with carbon monoxide were the focus of close attention at the trial. In October 2014, the appellant obtained a quotation from a supplier for a cylinder of carbon monoxide in a volume of 6.8 cubic metres and of 99.9 per cent purity. He spoke to Professor Qin Ling of the Orthopaedics and Traumatology Department of CUHK about conducting research on animals using the carbon monoxide. Professor Qin asked his assistant, Dr Dick Chow, to help the appellant with this. The appellant gave the quotation he had earlier obtained to Dr Chow who then arranged for the carbon monoxide and ten carbon monoxide detectors to be supplied to CUHK in April 2015.

9.With Dr Chow’s assistance, the appellant conducted an experiment using the carbon monoxide gas at CUHK on 13 May 2015. Blood drawn from an anaesthetised rabbit was saturated with carbon monoxide, apparently with a view to investigating oxygen treatment of victims of carbon monoxide poisoning. On 20 May 2015, again with Dr Chow’s assistance, the appellant conducted a further similar experiment on a live rabbit. After the experiment concluded on 20 May 2015, the appellant took out two empty yoga balls and filled them with carbon monoxide from the cylinder in the CUHK laboratory. In response to Dr Chow’s inquiry, the appellant explained that he wanted to take the carbon monoxide to his friend to conduct a purity test. He took the two yoga balls to his Toyota Alphard car which was parked in the carpark and spent the night with his girlfriend, Ms Lee.

10.The appellant admitted in a video recorded interview that he never intended to take the carbon monoxide in the yoga balls for a purity test. Instead, he claimed the real purpose of filling the yoga balls with carbon monoxide and taking them away was to kill rats at his house in Tai Tung Village. He also admitted that he had not mentioned the yoga ball which he had filled with carbon monoxide when the police were first investigating the deaths of Madam Wong and Lily because he was a coward and did not want to get Dr Chow in trouble and did not want his children to be without a parent should he be taken away. He was prepared to let people think the carbon monoxide emanated from the car itself.

11.On 21 May 2015, a Thursday and the day before the deaths of Madam Wong and Lily, when the appellant went to his car, he said he found that one of the carbon monoxide monitors which he had placed in the Toyota Alphard with the two yoga balls was sending out an alarm. He discovered that one of the two yoga balls was leaking so he emptied the carbon monoxide from the leaking yoga ball and brought the other yoga ball, still filled with carbon monoxide, home. The appellant claimed, in his video recorded interviews, that he brought the yoga ball filled with carbon monoxide from his car into the house late in the evening when he thought the children were in bed. However, he encountered Lily, who was not asleep, in the house and so told her that the yoga ball contained carbon monoxide which he intended to use to kill rats in the house over the weekend. He warned her not to touch the yoga ball. He did not tell anyone else in the household about the yoga ball.

12.On 22 May 2015, a Friday, Madam Wong drove the two younger children to school in her Mini Cooper car as usual. She returned home at 8.30 am and retired to her bedroom in the house at about 10 am. Lily was, unexpectedly, also at home as that day was a school holiday for her. The appellant was at home in the morning since he only had to work in the afternoon. He said he told Lily to stay at home to finish her homework and not to go out and reminded Madam Wong to reinforce that message to Lily. The appellant left home between 12.30 pm and 1 pm to attend a student presentation at CUHK at 1.30 pm. The couple’s helper, Siti, testified that she saw Madam Wong and Lily leaving home in the Mini Cooper at about 2 pm. She did not see them carrying anything to the car other than their own handbags. Madam Wong’s daily routine was to pick up her two younger children from school at about 4 pm.

13.It was the prosecution case that the appellant placed the yoga ball filled with carbon monoxide inside the Mini Cooper car, knowing that Madam Wong would drive the car later in the day on 22 May 2015. At some time, the prosecution contended, he removed the stopper from the yoga ball so that the gas would leak from it into the compartment of the car and so cause the occupant of the car to inhale carbon monoxide. This, the prosecution contended, was done deliberately by the appellant to kill Madam Wong, from whom he was estranged but did not wish to divorce and because he was now in a relationship with Ms Lee. Although the prosecution did not advance a positive case of financial motive, it was a fact that the appellant would acquire Madam Wong’s interest in two jointly owned properties and their joint bank accounts upon her death. The prosecution accepted that Lily was an unintended victim of the carbon monoxide gas from the yoga ball since her presence in the car was unexpected but the appellant was also guilty of her murder by reason of the doctrine of transferred malice or transferred mens rea.

14.The prosecution contended that the alleged research for which the appellant claimed he wanted the carbon monoxide was a sham and simply an excuse provided to conceal the real reason for acquiring the carbon monoxide, namely to kill his wife. He never had any genuine scientific reason for acquiring the carbon monoxide but instead planned to kill her with it from the outset. Alternatively, if he had any genuine scientific reason for acquiring the gas at the outset, he later decided to use it to kill her.

15.In support of the bogus nature of the research, the prosecution called evidence from the appellant’s supervisor, Professor Gavin Joynt, Chairman of the Department of Anaesthesia and Intensive Care of the CUHK. He testified he did not know anything about the appellant’s alleged research before he was interviewed by the police in their investigations into Madam Wong’s and Lily’s deaths. The appellant’s research proposal should have gone to Professor Joynt for approval of funds or personnel and, if animals were involved, an application to the Animal Experimentation Ethics Committee should also have been made through him. Professor Joynt also testified that the appellant’s research proposal was not well thought through and that, had it come before him for approval, he would have sent it back for major revision and he would not have forwarded it to the Ethics Committee for consideration. He could see no link between carbon monoxide poisoning and any of the appellant’s interests disclosed in his curriculum vitae.

16.The prosecution also called two other experts to support the view that the research proposal was of no value. Professor Kwong Yok-lam, Chair Professor of the Department of Medicine of the University of Hong Kong (“HKU”) testified that the research had no clinical benefit. Professor Michael Irwin, of the Department of Anaesthesiology of HKU, also testified that similar research had been carried out in the 1970s and was not new, proving only basic medical knowledge known for decades.

17.One of the two defence medical experts, Professor Nicholas Buckley, of the Medical School of the University of Sydney, agreed with Professor Joynt that if he were head of department or on the Ethics Committee when the appellant’s research proposal was presented to him, he would have sent it back to the appellant. Professor Buckley offered the view that the carriage of yoga balls filled with carbon monoxide was “crazy” and opined that a yoga ball full of carbon monoxide released into a courtroom would likely kill everyone inside.

18.The prosecution case was that there were only three possible candidates, namely the appellant, Madam Wong and Lily, who could have put the yoga ball in the car. The prosecution contended that the jury could be sure, by a process of elimination, that it was neither Madam Wong nor Lily who put the yoga ball in the car and therefore that it must have been the appellant who did so, intending to kill his wife and thus also, perhaps unintendedly, killing Lily.

The defence case

19.Professor Buckley and Dr Wang Chi Chiu gave evidence as medical experts for the defence. Professor Buckley agreed the appellant’s research proposal was rudimentary and crude but thought it might have scientific value and did not agree it was of no clinical relevance. Dr Wang, on the other hand, considered the proposal to be original and well planned. A colleague and friend of the appellant, Professor Leung Tak Yeung, gave evidence about their shared medical interests in obstetrics and gynaecology and testified that the appellant’s curriculum vitae showed he had done research on oxygen therapy, although there was nothing in it to show he had studied carbon monoxide poisoned patients.

20.The defence called an engineer, Professor Li Chi Kwong, to testify to tests he conducted on nitrogen, a yoga ball and a Mini Cooper. He criticised the approach of the prosecution expert, Dr Wong Koon Hung, but the engineers agreed that a fully inflated yoga ball would not fit in the car with its tailgate closed and that it could with about a quarter to a third of the gas let out.

21.A friend of Lily’s, Ms Eunice Li, gave evidence that Lily was good at her school subjects and that she was very scared of insects and rats. A family friend, Dr Victor Cheung, testified that Lily was happy and full of life when he last saw her and Madam Wong five days before they died.

22.The appellant did not give evidence at trial. Although he had raised the suggestion in his video recorded interviews that Lily was depressed and speculated she might have put the yoga ball in the car to commit suicide, the defence disavowed this theory as a positive case at trial. Instead, defence counsel[5] confirmed the defence did not have a positive case.

23.However, in closing submissions, counsel offered the alternative possibility that Lily had placed the yoga ball in the car and unplugged the stopper in order to kill insects, of which she was terrified, in the Mini Cooper and that the deaths of her and Madam Wong had therefore just been an accident.  That alternative theory has given rise to the issues raised in this appeal concerning the Judge’s directions about the allegedly missing stopper of the yoga ball to which we shall now turn.

The search for the stopper

24.As mentioned earlier, the police did not suspect that the yoga ball found in the Mini Cooper had anything to do with the deaths of Madam Wong and Lily at the initial stage of the investigation. Hence, no search was conducted for the stopper until about 6 months after the incident. PW 17 was the exhibit officer and he testified that the yoga ball in the Mini Cooper was seized as an exhibit from its boot on 25 November 2015. On that occasion, he had made a search for a stopper in the car and could not find anything that could serve that purpose.

25.PW 17 did not attend the scene on 22 May 2015. His first examination of the vehicle and the boot was shortly after midnight on 23 May 2015. By then, the Mini Cooper was parked at Ma On Shan Police Station. Whilst there were photos taken at the scene regarding the boot, and the yoga ball was shown to be in different positions in the photos, PW 17 did not take those photos and did not know what happened when other police officers examined the car at the scene. Based on the photos taken at the scene, the articles in the boot had been rearranged in the course of the examination. PW 17 postulated that to be the case and the Judge also referred to the fact the yoga ball had been moved as shown in the two photos .

26.On 28 May 2015, a government motor vehicle examiner conducted an examination of the mechanical function of the Mini Cooper.[6] However, there was no evidence as to the extent to which such examination involved removing or rearranging the articles in the boot. In any event, the evidence shows that the articles in the boot had been moved around.

27.Although it was an admitted fact that, prior to their being produced as exhibits in court, the exhibits themselves had never been tampered with unless authorized for handling, there was no reference to the missing stopper or any search for it in the admitted facts.

28.As we shall see, the reliance placed on the missing stopper changed in the course of the trial.

The closing speech of the prosecution regarding the stopper

29.In light of the reference in the appellant’s cautioned interview to the possibility of Lily having committed suicide as the reason for the presence of the yoga ball in the Mini Cooper, the prosecution adduced evidence to rebut this suggestion.

30.Whilst the missing stopper has no logical probative value in rebutting such possibility, prosecuting counsel made a reference to a stopper found amongst the items in the drawer of a filing cabinet in the appellant’s room in the house when a search was conducted on 13 May 2016. Counsel reminded the jury that the search took place almost one year after the incident. But he put forward the following suggestion to the jury:

“You might ask yourself, was that the yoga ball pulled out of the --- was that from the yoga ball that was placed in the Mini? Again, the best I can do with that, one strand of rope. It might break, it might not. Put it together with everything else. Now, as I say, the qualification to that is it’s a year later or thereabouts. So it is some evidence, though.”

31.There was no evidence to connect the stopper found in the drawer with the yoga ball in the Mini Cooper. Other yoga balls were found in the appellant’s home when it was searched.

32.We shall have to examine whether the stopper found inside the appellant’s drawer could be regarded as a strand in the rope constituting part of the circumstantial evidence pointing to the inference that the appellant was the person who put the yoga ball in the Mini Cooper. We shall also need to examine whether the Judge should have given the jury specific directions regarding this suggestion in the particular circumstances of this case.

The defence’s closing speech  

33.In his closing speech, defence counsel disavowed running a positive case that Lily used the yoga ball to commit suicide though he also tried to explain why such suggestion was put forward by the appellant in the recorded interview under caution. Shifting the focus, as mentioned above, he articulated for the first time the suggestion that Lily might have used the gas in the yoga ball to kill insects in the Mini Cooper.

34.Counsel did not attach any significance to the fact that no stopper could be found in the car’s boot in November 2015 though he cast doubt on the officer’s reliability. He also commented upon the lack of evidence as to the state of the boot since the police only took photos about 4 hours after they had arrived at the scene and the articles in the boot had been moved around.

35.Nothing was said by defence counsel in relation to prosecuting counsel’s reference to the stopper found in the drawer during the search of the house on 13 May 2016.

The Judge’s directions to the jury on the stopper

36.The Judge did not specifically allude to the stopper found in the drawer on 13 May 2016 in her summing up to the jury. She however did give directions to the jury on the assessment of circumstantial evidence with reference to strands in a rope:

“So you will have to consider all the circumstantial evidence that happened in this case, that I have mentioned in this case, all the matters that I have reminded you about; the different strands, threads and tested, consider, pull it, does it break or not. If it does not break, if it stays intact how many pieces of thread you have got, twist them together to make the rope. Is it a thick rope or is it only like two strings and so a very thin rope?”

37.She also directed the jury that they should not speculate:

“Finally, you should be careful to distinguish between arriving at conclusions based on reliable circumstantial evidence and mere speculation. Speculating in a case amounts to no more than guessing or making up theories without good evidence to support them. Neither the prosecution, the defence nor you should do that.”

38.The Judge addressed at some length in her directions the possibility that Lily might have used the gas in the yoga ball to kill insects. She thought it was possible to eliminate that possibility based on the evidence of PW 17 regarding the absence of a stopper when he searched the car on 25 November 2015. The crucial parts of such directions were as follows:

“… if you are sure that the officer was correct that he searched through the whole car and there was no yoga ball stopper or plug found, you may consider then if Lily had been using the yoga ball just to try to get the gas out to kill insects, what happened to the plug? I mean there was no reason for her to throw away the plug. I mean would it not be just there because she was only trying to get the gas out?

So if you are sure that the exhibit 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. There is just no plug at all to stop the gas from coming out and even afterwards, there would not be any plug to show you that originally there was a plug to this yoga ball before it became deflated. So that might help you when you consider who would have --- who had the --- who had done it actually, who put the yoga ball in the Mini Cooper.”

39.This was said in the context of the prosecution establishing its case by eliminating Lily as the person who put the yoga ball in the Mini Cooper. The Judge did not, however, give any directions to the jury to consider what could have happened to the articles in the boot prior to 25 November 2015. Instead, by her process of deduction, the possibility of Lily using the carbon monoxide to kill insects was to be determined by reference to the reliability of the evidence of PW 17.

The errors in the directions

40.It is normally unnecessary to give the jury any special direction on how they are to approach circumstantial evidence. Whilst there may be exceptional circumstances calling for special directions on the drawing of inferences, whether, and what, special directions should be given is a matter within the discretion of the trial judge. The trial judge should also consider the risk that a special direction might confuse the jury having regard to the issues they have to decide, the rest of the evidence in the case and the other directions which the jury will be given.[7]

41.In cases where special directions on circumstantial evidence are given, such directions must be tailored to the circumstances of the case by reference to the evidence and arguments advanced by the parties. This Court endorsed the guidance given in the Crown Court Bench Book March 2010 issued by the Judicial Studies Board in England and Wales regarding directions on circumstantial evidence.[8] Such guidance reminded judges that the directions should draw the jury’s attention to the defence case as to the disputed evidence.

42.In the present case, counsel for the appellant[9] does not contend that the Judge was in error to have given a special direction with regard to the possibility of Lily using the yoga ball to kill insects. We agree. Bearing in mind that defence counsel at trial only raised that possibility in his closing speech (so that prosecuting counsel never had the opportunity to address that suggestion), we do not think it could be suggested that the Judge erred in addressing it in her summing up.

43.The real issue is whether applying the Judge’s process of deduction based on the relevance of the missing stopper to the assessment of the possibility of Lily using the carbon monoxide to kill insects in the car, she had failed to refer to important relevant circumstances, in particular the defence argument as to the evidential gap regarding the search for the stopper prior to 25 November 2015, and thereby unwittingly confused the jury.

44.With great respect, although the Judge gave a very thorough summing up in every other aspect of the case, we have come to the conclusion that her directions regarding the stopper could have steered the jury towards an impermissible line of reasoning in rejecting the possibility of Lily using the carbon monoxide to kill insects.

45.First, she directed the jury to concentrate on the reliability of the evidence of PW 17 with regard to his search for the stopper and invited them to reason that, if they were sure he was correct, they would be able to tell who had put the yoga ball in the car. The premise was that if it were established that the stopper could not be found, Lily could not be that person and the scenario of her using the carbon monoxide to kill insects could be eliminated. In so doing, the Judge in effect allowed the jury to ignore the possibility of the stopper being displaced or mistakenly taken away before the search of the car was conducted on 25 November 2015.

46.Given the time lapse between the deaths and the search and the handling of the car and the contents of its boot in the interim, such possibility could not be discounted. It should at least have been a matter for the jury to deliberate upon and the Judge’s directions did not draw the jury’s attention to the need to conduct such deliberation.

47.Instead, on the directions given by the Judge, there was a risk that the jury might have rejected the suggestion that Lily was the person who placed the yoga ball in the car once they found the evidence of PW 17 to be reliable.

48.Secondly, the prosecution did not adduce any evidence in respect of securing the safe custody of all the items found in the car boot after the arrival of the police at the scene. As mentioned above, it is not disputed that articles in the boot had been moved. In his closing speech, in addition to his attack on the reliability of PW 17’s evidence, defence counsel had alluded to that fact. Further, the yoga ball and the stopper were not the focus of the early stages of the police investigation.   

49.Before us, counsel advanced opposing views as to whether there is any evidential basis for suggesting that the stopper was missing at the time of incident. Relying on Shepherd v The Queen [10] counsel for the prosecution[11] submitted that while the prosecution bears the burden of proving all the elements of an offence beyond reasonable doubt, it does not mean that every fact or every piece of evidence relied upon must itself be proved beyond reasonable doubt. She highlighted the following observations by Dawson J in Shepherd:

“…But the jury may quite properly draw the necessary inference having regard to the whole of the evidence, whether or not each individual piece of evidence relied upon is proved beyond reasonable doubt, provided they reach their conclusion upon the criminal standard of proof. Indeed, the probative force of a mass of evidence may be cumulative, making it pointless to consider the degree of probability of each item of evidence separately.”

50.On the other hand, Mr Grounds submitted that the issue of the missing stopper is not the usual “strand in a rope” situation. It was an indispensable basis for the inference of guilt and therefore according to Shepherd would have to be proved beyond reasonable doubt before Lily could be eliminated as the person who put the yoga ball in the Mini Cooper. Counsel placed reliance on the following dicta of Dawson J in Shepherd:

“… it may sometimes be necessary or desirable to identify those intermediate facts which constitute indispensable links in a chain of reasoning towards an inference of guilt. Not every possible intermediate conclusion of fact will be of that character. If it is appropriate to identify an intermediate fact as indispensable it may well be appropriate to tell the jury that that fact must be found beyond reasonable doubt before the ultimate inference can be drawn.”[12]

51.In Hong Kong, Shepherd has been adopted and applied in the Court of Appeal in HKSAR v Au Hau-ching[13] and HKSAR v Tsang Chi Wai.[14]  An application for leave to appeal to the Court of Final Appeal was made in Au Hau-ching and the Appeal Committee dismissed it[15] with an endorsement of the approach adopted by McHugh J in Shepherd. The approach is to be found in the following parts of His Honour’s judgment:

“Ordinarily, in a circumstantial evidence case, guilt is inferred from a number of circumstances --- often numerous --- which taken as a whole eliminate the hypothesis of innocence. The cogency of the inference of guilt is derived from the cumulative weight of circumstances, not the quality of proof of each circumstance.

In a particular case, an inference of guilt beyond reasonable doubt may not be able to be drawn unless each fact relied on to found the inference is established beyond reasonable doubt. This is likely to be the case where the incriminating facts relied on to establish the inference are few in number. But the more facts that are relied on to found the inference of guilt, the less likely it is that each or any fact will have to be proved beyond reasonable doubt to establish guilt beyond reasonable doubt. Consequently, even when guilt beyond reasonable doubt cannot be inferred unless certain facts are proved, it may still be open to infer guilt beyond reasonable doubt even though each fact is not proved to that standard. Thus, in the example that I have given, the facts proved on the balance of probabilities were essential to the determination of guilt beyond reasonable doubt. But the determination could still be made even though all those facts were not proved beyond reasonable doubt.”[16]

52.Thus, it is still necessary to prove the facts from which the inference is to be drawn, even though such facts or some of them may be proved on the balance of probabilities as opposed to the standard of beyond reasonable doubt. The approach in Shepherd does not permit a tribunal of fact to draw an inference based on conjecture.

53.In Nina Kung v Wong Din Shin,[17] Ribeiro PJ highlighted the proper discipline in drawing inferences by reference to circumstantial evidence:

“… Where … the court is invited to reach a conclusion of forgery as an inference to be drawn on the basis of circumstantial evidence, any such inference must be properly grounded in the primary facts found…” (our emphasis)

54.His Lordship also cited from the judgment of Kitto J in Jones v Dunkel & Another:[18]

“One does not pass from the realm of conjecture into the realm of inference until some fact is found which positively suggests, that is to say provides a reason, special to the particular case under consideration, for thinking it likely that in that actual case a specific event happened or a specific state of affairs existed.” (our emphasis)

55.In the present context, the Judge invited the jury to eliminate the possibility of Lily putting the yoga ball in the car based on a finding that the stopper was missing. However, the mere fact that PW 17 could not find the stopper on 25 November 2015 could not establish that the stopper was missing on 22 May 2015 unless one were to draw an inference as to the state of the boot on 22 May 2015 based on its state as found by PW 17 on 25 November 2015. Given the lapse of time and the handling of the articles in the boot in the interim, and bearing in mind that the initial focus was not on the yoga ball and its stopper, we do not think it was open to the jury to draw that inference.

56.Once we reach that conclusion, it is not necessary for us to consider Mr Grounds’ submission on the need to establish that the stopper was missing on 22 May 2015 beyond reasonable doubt. Since counsel have not referred us to subsequent authorities addressing that aspect of the Shepherd approach,[19] we shall refrain from expressing any view on the point.

57.Given our conclusion that there was no evidential basis at the trial for proceeding on the basis that the stopper was missing on 22 May 2015, the Judge’s directions in question were erroneous. In any event, we should not be taken to be accepting the logic of the Judge’s underlying premise that the fact the stopper might have been missing on 22 May 2015 necessarily provides a proper basis for eliminating Lily as the person who placed the yoga ball in the car.

58.Further, the fact that a stopper was found in the appellant’s drawer on 13 May 2016 would not be relevant given the absence of a proper basis for a finding that the stopper of the yoga ball was missing on 22 May 2015.

59.Moreover, as there were other yoga balls in the house, a spare stopper found in the drawer could not by itself be a matter of significance. It did not have strong probative value in terms of proving that the appellant was the person who put the yoga ball in the Mini Cooper on 22 May 2015. In the absence of any evidence linking the stopper found in the drawer with the yoga ball in the car, the closing remarks of prosecuting counsel in that regard were highly prejudicial. In such circumstances, the Judge should at least have drawn the attention of the jury to the fact that there was nothing to connect the stopper in the drawer with the yoga ball in the car.

60.Without such directions, there is a risk that the jury could have committed the error of heaping a false inference that the stopper in the drawer was the stopper of the yoga ball in question (which is no more than conjecture) upon another false inference that the stopper of the yoga ball was missing at the time of the incident (which is not an inference that can be drawn on the evidence). On such impermissible reasoning, a juror might have treated the discovery of the stopper in the appellant’s drawer as a very strong indication that he was the person who removed the stopper from the yoga ball in the Mini Cooper.

61.Unfortunately, the Judge’s direction on the missing stopper could have compounded that risk by pre-empting the jury from conducting a proper assessment of the evidence as to whether the stopper of the yoga ball was actually missing on 22 May 2015.

62.Ms Chan placed reliance on the Admitted Facts and the absence of cross-examination of PW 17 with regard to the search for the stopper at the trial. Such reliance is misplaced since:

(1)  The Admitted Facts did not contain an admission by the appellant that the stopper was missing on 22 May 2015;

(2)  Defence counsel had commented upon the lack of evidence as to the handling of the articles in the boot and the late search for the stopper in his closing speech; and

(3)  PW 17 did not give any evidence as to securing the articles in the boot prior to his search for the stopper. He admitted that other police officers might have handled these articles on 22 May 2015. In light of that, defence counsel had no obligation to cross-examine him.

63.Though defence counsel did not raise any objection to the Judge’s directions at the trial, we are satisfied that such directions were material and the jury might have embarked on the impermissible line of reasoning we have identified above in reaching their verdict. The Court of Appeal, like the Judge, failed to have regard to the lack of evidence on safe custody of the articles in the boot prior to the search on 25 November 2015 and, with respect, its conclusions that the Judge gave appropriate directions on circumstantial evidence and inferential reasoning (at [86] of its judgment) and in respect of the issue of the missing stopper (ibid. at [244]) cannot stand in light of the errors identified above.

Disposition of the appeal

64.Having held that the judge’s directions about the stopper amounted to a misdirection in law, it falls to decide the disposition of this appeal. The prosecution contends that the case is an appropriate one for the application of the proviso to section 83(1) of the Criminal Procedure Ordinance (Cap. 221) and that the appeal should be dismissed notwithstanding the decision in respect of the judge’s directions about the stopper being decided in favour of the appellant. The appellant, on the other hand, contends that this is not an appropriate case for the application of the proviso and that the appellant’s convictions should simply be quashed. It is accepted by the appellant that, in that event, it would be appropriate to order a retrial.

65.Section 83(1) of the Criminal Procedure Ordinance (Cap. 221) states:

“Except as provided by this Ordinance, the Court of Appeal shall allow an appeal against conviction if it thinks –

(a) that the conviction should be set aside on the ground that under all the circumstances of the case it is unsafe or unsatisfactory; or

(b) that the judgment of the court of trial should be set aside on the ground of a wrong decision on any question of law; or

(c) that there was a material irregularity in the course of the trial,

and in any other case shall dismiss the appeal:

Provided that the Court of Appeal may, notwithstanding that it is of opinion that the point raised in the appeal might be decided in favour of the appellant, dismiss the appeal if it considers that no miscarriage of justice has actually occurred.”

66.The Court of Final Appeal is empowered, by section 17(2) of the Hong Kong Court of Final Appeal Ordinance (Cap. 484), to exercise any of the powers of the courts from which the appeal lies. The Court of Appeal’s power to apply the proviso in section 83(1) is one such power and it is well established that the test to be applied when the proviso is invoked is whether a reasonable jury, properly instructed, would, on the evidence, without doubt convict or would inevitably come to the same conclusion: Ewan Quayle Launder v HKSAR.[20]  This Court has adopted the same test in many cases,[21] and the proviso can be,[22] and has been,[23] applied to affirm convictions in appeals involving charges of murder. In applying the test, the Court considers the reasonable hypothetical jury and not the jury that convicted the appellant.[24]

67.In considering whether the case is suitable for the application of the proviso, it is clearly important to look at the point that is being decided in favour of the appellant in order to determine if, by application of the proviso, no miscarriage of justice can be said to have occurred. The test, as already indicated, is that any reasonable jury would inevitably come to the same conclusion and convict.

68.Ms Chan contended that this was an appropriate case to apply the proviso “because the evidence against the Appellant is so overwhelming that on the circumstantial evidence as a whole, any reasonable jury properly directed would have convicted him”.[25] Ms Chan submitted that the circumstantial evidence amounted to “many threads in the thick rope”[26] and consisted of inculpatory evidence with regard to, amongst other things, the appellant’s reason for acquiring the carbon monoxide gas, his filling the yoga balls with carbon monoxide, taking the yoga balls home and implicating Lily, and concealing his connection with the carbon monoxide when told by the police that the cause of death of his wife and daughter was carbon monoxide poisoning.

69.We have considered these matters which the prosecution submits support the application of the proviso in this case. We are not persuaded that this is a suitable case for its application. On the contrary, we are persuaded that Mr Grounds is correct in submitting that the proviso should not be applied in the present case.

70.Here, as will already be apparent, the point decided in favour of the appellant on the appeal is that the judge’s directions in relation to the stopper were flawed. It is necessary to look at the misdirections in context in order to determine what significance they have.

71.As already noted, the prosecution case that it was the appellant who placed the yoga ball in the Mini Cooper and removed the stopper to release carbon monoxide gas into the compartment of the car proceeded on the application of a process of elimination. The prosecution opened the case on the basis that identifying the person who put the yoga ball in the car was key and highlighted that much of the evidence would be devoted to eliminating Lily as the one person the appellant suggested might have done so. In closing, the prosecution put its case thus:

“How the case for the prosecution proceeds is by a process of elimination. The aim of this is to eliminate all other realistic candidates. The case for the prosecution is that once you go through this process of elimination, there is one person and one person only that is left; the accused.”

72.In her summing up to the jury, the judge repeatedly reminded the jury that the prosecution case was that, by a process of elimination, they could be sure that the only person who could have put the yoga ball in the car was the appellant. As discussed above, it was in this context that the judge came to address the question of the significance of the stopper and how that might assist the jury in deciding whether Lily could be eliminated as a candidate. As Mr Grounds pointed out, the judge referred to the yoga ball being found in the car “without any stopper or plug” at the outset of her summing up and referred again to the absence of the stopper or its removal from the yoga ball approximately 20 further times in the course of her summing up.

73.The consequence of the judge’s summing up in the present case is that the appellant has cause to complain that, by reason of the misdirections complained of, he was deprived of a fair trial. His defence, that it was not proved beyond reasonable doubt that it was the appellant who put the yoga ball in the car and removed its stopper was not fairly put because the possibility that it was Lily who did so was not properly left to the jury by the judge in the summing up. Instead, because of the misdirections discussed earlier in this judgment, the jury were invited to eliminate Lily as a possible candidate on the basis of an impermissible line of reasoning.

74.The test for the proviso requires the appellate court to be satisfied that any reasonable jury, properly directed, would inevitably convict. It is not enough that the appellate court takes the view that it would have convicted the appellant. Instead, the question to be asked is whether, if the hypothetical jury had not been given the stopper misdirections, it would, on the evidence before the court, inevitably have convicted. Here, the facts of this case are, on any view, most unusual. The mechanics of the alleged murders are exceptional, if not unique, and require a number of questions to be determined by the jury against the appellant if a conviction is to be supported. We are not persuaded that the hypothetical reasonable jury, properly directed by not being given the stopper misdirections, would inevitably have convicted. That is because the available evidence in support of the prosecution case based on elimination of Madam Wong or Lily being the person who put the yoga ball in the car, when deprived of what became the important plank of the Judge’s stopper directions, leaves room for doubt as to how that process of elimination would have been handled by the hypothetical reasonable jury. The evidence ought therefore to be assessed by a fresh jury on a retrial and not by the appellate court postulating the inevitability of conviction.

75.For these reasons, this is not, in our view, an appropriate case for the application of the proviso.

76.We would therefore allow the appellant’s appeal, quash his convictions and order his retrial on the charges of murder.

Madam Justice McLachlin NPJ:

77.I agree with the joint judgment of Mr Justice Fok PJ and Mr Justice Lam PJ.

Chief Justice Cheung:

78.The Court therefore unanimously allows the appellant’s appeal, sets aside his convictions and orders a retrial on the charges of murder.

Mr Christopher Grounds, Mr Andrew Bullett and Mr Franco Kuan, instructed by CL & Co Solicitors, for the Appellant

Ms Christal Chan, ADPP and Mr Ira Lui, ADPP, of the Department of Justice, for the Respondent