HKSAR v. Tsang Kai on

CACC 177/2015

IN THE HIGH COURT OF THE

HONG KONG SPECIAL ADMINISTRATIVE REGION

COURT OF APPEAL

CRIMINAL APPEAL NO 177 OF 2015

(ON APPEAL FROM DCCC 1015 OF 2014)

------------------------

------------------------

--------------------------------------

REASONS FOR JUDGMENT

--------------------------------------

Introduction

1.The applicant faced trial in the District Court before District Judge Douglas TH Yau (“the judge”) on a charge sheet containing a single charge of burglary, contrary to section 11(1)(b) and (4) of the Theft Ordinance, Cap 210. 

2.The Particulars of Offence allege that the applicant, on 10 January 2014, having entered as a trespasser part of a building known as Flat E, 13/F, Crystal Court, No 6 Man Wan Road, Ho Man Tin, Kowloon, stole therein a quantity of jewellery and currency and two bank passbooks. 

3.On 20 May 2015 the applicant was convicted by the judge of this charge.  On the same day he was sentenced to 3 years and 3 months’ imprisonment.  Subsequent to his conviction he applied for leave to appeal his conviction.

4.At the hearing of his application I allowed it, but granted leave to appeal only in respect of the first and third grounds of appeal and said I would give my reasons for doing so at a later date.  This I now do.

The trial

5.The prosecution’s case was, in fact, a very simple one.  It was that the victim’s flat was burgled on 10 January 2014 and the items particularized in the charge were stolen from it.  No one was at home at the time the burglary took place.  Within the flat there was a wooden jewellery box and when it was sent for forensic examination it was found to contain a sample of DNA which was subsequently found to match the DNA of the applicant.  

6.There was no other evidence implicating the applicant in this crime and it was the prosecution’s case that the DNA match proved that the applicant had had contact with the wooden box and that, given the circumstances of the location and storage of the box, the only reasonable, and the irresistible, inference was that the applicant had been inside the flat as a trespasser, had handled the wooden box, and that he had stolen the particularized items.

7.The applicant did not give evidence in the trial but put the prosecution to strict proof of its case.  His counsel attacked the DNA evidence in two ways.  The first was to suggest that the wooden box which had been seized by the police officer had not been properly stored as it had not been sealed within a tamper proof envelope. Aligned with this attack was a question mark around how the plastic envelope in which the box was placed and which the handling police officer stapled closed, came to be heat sealed closed when it was opened at the government laboratory.

8.The second way in which an attack was mounted on the DNA evidence was to call evidence in the defence case from the sister of the applicant who testified as to the relatives of the applicant.  This was with a view to suggesting that the evidence of the Government Chemist could not be relied upon because the statistics that she created of random match probabilities (“RMP”) did not take into account the fact that the applicant had relatives. 

9.In response to this evidence the prosecution obtained another report from the Government Chemist in which she provided other RMP statistics that took account of the existences of relatives of the applicant.  The prosecution application to produce this evidence in rebuttal was opposed but the judge allowed the prosecution to adduce it.  

The Reasons for Verdict

10.After setting out the evidence the judge dealt with the application by the prosecution to call rebuttal evidence.  The judge said that when determining such an application one significant factor is whether the previously unknown evidence was actually reasonably foreseeable by the party now seeking to adduce it.  The judge found that the prosecution could not have foreseen the line of defence raised by the applicant’s counsel.  He said:

“I found that in the interest of justice and based on the circumstances of the disclosure of the defence’s evidence, the prosecution should be allowed to recall Ms. Wong to rebut the evidence of the defence that the RMP would be similar to those as stated in the quoted articles given the siblings and relatives number of the defendant.”

11.The judge then went on to make his findings and to analyse the evidence. Noting that the applicant had not given evidence he said that the consequence was that “there is no evidence from the defendant himself to undermine, contradict or explain the evidence put before the court by the prosecution.”

12.He then went on to direct himself on the proper approach to be taken to the analysis of DNA evidence and no criticism is made of his directions.

13.The judge found that the applicant’s DNA sample did match that of the DNA sample found on the wooden box.  He accepted and gave full weight to the evidence of the forensic analyst.  He said even as adjusted, the statistical RMP still represented “a very low possibility of the sample being from someone other than the defendant.”  He also found that there was no evidence that any of the applicant’s siblings or relatives had the opportunity to come into contact with the wooden box and said it was inherently improbable that the applicant’s DNA might somehow be directly left on the wooden box given the circumstances of its safe keeping. 

14.The judge then went on to discuss the second attack upon the the DNA evidence, namely the suggestion that the wooden box had not been properly stored and might have been tampered with between the time of its seizure and its examination by the Government Chemist.  He said he was satisfied from the police officer’s evidence that the contents of the plastic bag had not been contaminated while it had been in his custody.  He further found that it was inherently improbable that the applicant’s DNA would be able to come into contact with the wooden box once it had been placed inside the police plastic bag.  He said there was no evidence that the applicant had come into contact with the plastic bag or its contents.  Furthermore, there was no evidence that the applicant had been to premises of the government laboratory or that his DNA sample had, prior to his examination of the wooden box, been inside the laboratory premises.  In fact no match had originally been found for the sample contained in the wooden box and it was only later when the Government Chemist was given the applicant’s DNA sample that it was found to match the sample previously obtained from the wooden box.

15.In respect of the difference between the police officers’ evidence that he had stapled closed the plastic bag in which the wooden box was contained and the Government Chemist’s evidence that the plastic envelope in which she received the wooden box was heat sealed closed the judge said:

“The bag containing the wooden box was heat sealed when it came to Ms. Wong for her analysis. The only irresistible inference was that it was heat sealed by the staff of the government laboratory. I accept Ms. Wong’s evidence that she found that the DNA sample from the wooden box had not been contaminated.”

16.The judge also found that it was inherently improbable that the applicant’s DNA could be indirectly placed on the wooden box once it was with the government laboratory.  He then went on to make the final conclusion in respect of the DNA evidence saying:

“… given the scientific evidence and circumstances surrounding the case, the defendant is the person who had left the DNA sample on the wooden box and, for the following inferences, he is not innocent.”

17.The judge went on to list those irresistible inference which were that the applicant was inside the flat when he had direct contact with the wooden box, he was inside the flat as a trespasser and having entered as a trespasser, he intended to steal from the flat.  The judge then made the final finding that it was the applicant who stole the items particularized in the charge and he convicted him accordingly.   

The grounds of appeal

18.The applicant relies upon four grounds of appeal in his Perfected Grounds of Appeal Against Conviction.  The first is that the judge erred in allowing the prosecution to call rebuttal evidence in the form of the supplementary report of the Government Chemist that took into account the existence of relatives of the applicant.

19.The second ground of appeal is that the judge erred in coming to the conclusion that the bag containing the wooden box was heat sealed by staff of the government laboratory when there was no evidence from the prosecution to enable such a finding to be made.  It is also part of this ground of appeal that the judge wrongly concluded that the chain of evidence in the handling of the wooden box had been established.

20.The third ground of appeal is that the judge erred in excluding the possibility that the biological substance from which the DNA of the applicant was extracted was not deposited on the box by the applicant.  This ground of appeal asserts that the substance could have been deposited on the wooden box through another, the true burglar, who had been in contact with the applicant, without the applicant actually coming into contact with the wooden box or being at the scene of the crime.

21.The final ground of appeal asserts that the judge erred by taking into account the lack of any evidence that the applicant had been to the premises of the government laboratory and to draw an irresistible inference that the wooden box had not been contaminated before it got to the government laboratory.  In support of this ground of appeal it is also argued that the judge wrongly used the applicant’s failure to testify to strengthen the prosecution’s case when the prosecution had in fact fallen short of proving its case beyond reasonable doubt. 

Discussion

22.The first ground of appeal raises the issue of what probability statistics should be included in a DNA report in order to give the tribunal of fact a complete picture so that it can determine what weight should be given to the probability statistic as a piece of evidence probative of the guilt of the accused.  It has to be remembered that unlike fingerprints, which are unique, DNA may match and so the DNA expert provides a report based upon the probability of finding a match, within the general population, to the DNA found at the crime scene. 

23.The probability statistic that does not take into account relatives of the defendant is the RMP.  In the English cases it is referred to as the random occurrence ratio.  It is defined by the Government Laboratory report as the probability “that a randomly selected person in the local Chinese population unrelated to the donor … would have the matching DNA types found.”  Because it focuses on random matches the probability statistic will usually be extremely low.  For this applicant it was 1 in 11.7 quadrillion.  The higher the figure, the lower the probability that a match will be found.  The lower the probability of such a match being found the more probative is the DNA evidence and the more likely it will allow of an inference by the tribunal of fact that the source of the crime scene DNA was the defendant. 

24.However, when relatives of the same gender are taken into account the statistical matching probability rises significantly depending upon the relative.  In the present case the “match probability”[1] for a full sibling of the applicant is 1 in 1.81 million.

25.It is the applicant’s case that it was reasonably foreseeable by the prosecution that matching probabilities, and not just RMP, would be needed in this applicant’s case and that the judge erred in allowing the prosecution to plug a loophole in its DNA report which otherwise would have so reduced the probative value of the DNA evidence that it could not have proven the guilt of the applicant beyond reasonable doubt.  Ms Cheung, counsel for the applicant, argues that before the judge can take into account matters such as prejudice to the defendant and the interests of justice in determining whether to allow the prosecution to re-open its case, he has to be satisfied that the prosecution has overcome the hurdle of showing that the need for the evidence was not reasonably foreseeable. 

26.This ground of appeal also raises the question of whether the Government Laboratory should in every case, as a matter of course, include matching probability statistics of the relevant gender.  In the present case that would be father, brother, uncle or nephew and male first cousin.

27.I am satisfied these are all matters that should be addressed by the Court of Appeal and I grant leave to appeal on this ground.

28.The second ground of appeal complains that the judge drew an inference that was not available to him to draw from the primary facts.  This is purely an issue of fact and on the material available to me from the judge’s Reasons for Verdict.  I am not persuaded that it is a reasonably arguable ground of appeal.  I do not grant leave to appeal on this ground.

29.The third ground of appeal raises the question of how far the prosecution has to go in excluding alternative possible means of exculpatory contact between the defendant and the crime scene in order for the DNA evidence to have probative value, especially in a situation, such as the present case, where the DNA evidence is the only evidence to link the defendant to the crime.  Ms Cheung argues that this becomes particularly important when the source of the DNA is a biological substance that is easily shed by an individual and can be transported on the body of another.  For example, skin cells could fall into this category but semen could not.

30.Ms Cheung relies on English cases which suggest that when the DNA comes from a movable source and there is no other evidence whatsoever to link the defendant to the crime then the DNA evidence is unlikely to be capable of proving guilt beyond reasonable doubt.  Here, she argues the source of the DNA was shed skin cells, such as dandruff, and it could easily have been inadvertently deposited at the crime scene by someone who had had contact with the applicant.  She also relies on the fact that the DNA source cannot be dated and so it could have been deposited onto the wooden box at any time over a period of many years.

31.Notwithstanding that the legal issues raised by Ms Cheung are likely to be fact sensitive and dependant upon the circumstances of each particular crime and crime scene I am persuaded that I should grant her leave to argue this ground of appeal.

32.The fourth ground of appeal raises a purely factual issue relating to the inferences the judge drew in respect of the chain of evidence and the risk of contamination of the DNA on the seized wooden box. It is very much dependent on the second ground of appeal to have any chance of success.  I am not persuaded, on the contents of the judge’s Reasons for Verdict, that this ground of appeal is reasonably arguable and I do not grant leave to appeal in respect of this ground.

Conclusion

33.For these reasons I granted the applicant leave to appeal against conviction but only on grounds 1 and 3 of the Perfected Grounds of Appeal Against Conviction.

Mr Prakash L Daryanani SPP, of the Department of Justice, for the respondent

Ms Karen Cheung, instructed by Director of Legal Aid, for the applicant

[1] This is the term used by the Government Laboratory in contradistinction to RMP.