Cb v. Commissioner of Police, Secretary for Justice, Secretary for Security

Press Summary (English)

Press Summary (Chinese)

FACV No. 1 of 2025

[2025] HKCFA 10

IN THE COURT OF FINAL APPEAL OF THE

HONG KONG SPECIAL ADMINISTRATIVE REGION

FINAL APPEAL NO. 1 OF 2025 (CIVIL)

(ON APPEAL FROM CACV NO. 208 OF 2022)

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BETWEEN

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JUDGMENT

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Chief Justice Cheung and Mr Justice Fok PJ:

A.      Introduction

1.The judicial review concerns the right conferred by Article 4(3) of the Hong Kong Bill of Rights (“BOR4(3)”) not to be subjected to forced or compulsory labour and the duty of the Government of the Hong Kong Special Administrative Region (“HKSARG”) to comply with its positive obligations under Article 4 of the Hong Kong Bill of Rights (“BOR4”).  It arises in a case concerning the employment of the appellant as a domestic helper by an employer who was alleged to have abused and indecently assaulted her.  The courts below held that there had been investigative failures in respect of the case which amounted to breaches of the appellant’s rights under BOR4(3).  The first instance judge held that those breaches were caused by the absence of a bespoke criminal offence criminalising forced labour[1] but this holding was overturned by the Court of Appeal.[2]  The Court of Appeal granted the appellant leave to appeal to this Court against that reversal.[3]

2.BOR4 provides for the protection of persons from various severe forms of exploitation, including slavery and servitude as well as forced or compulsory labour, in the following terms:

“Article 4

No slavery or servitude

(1) No one shall be held in slavery; slavery and the slave-trade in all their forms shall be prohibited.

(2) No one shall be held in servitude.

(3) (a) No one shall be required to perform forced or compulsory labour.

(b) For the purpose of this paragraph the term ‘forced or compulsory labour’ shall not include –

(i) any work or service normally required of a person who is under detention in consequence of a lawful order of a court, or of a person during conditional release from such detention;

(ii) any service of a military character and, where conscientious objection is recognized, any national service required by law of conscientious objectors;

(iii) any service exacted in cases of emergency or calamity threatening the life or well-being of the community;

(iv) any work or service which forms part of normal civil obligations.”

3.BOR4 is derived from and is in the same terms (subject to one minor variation not materially relevant to the present case) as Article 8 of the International Covenant on Civil and Political Rights (“ICCPR” and “ICCPR8”).  BOR4/ICCPR8 are also similar to Article 4 of the European Convention on Human Rights (“ECHR” and “ECHR4”): see ZN v Secretary for Justice (2020) 23 HKCFAR 15 at [28].

4.BOR4 has previously been addressed by this Court in ZN v Secretary for Justice (2020) 23 HKCFAR 15 (on appeal from the Court of Appeal in ZN v Secretary for Justice [2018] 3 HKLRD 778), a case concerning a Pakistani national who had been subjected to very serious abuse, physical violence and restrictions on his movements while employed as a domestic helper in Hong Kong over a period of four years.  We shall refer below to those decisions as ZN(CFA) and ZN(CA) respectively.

5.Two questions of law were involved in the appeal in ZN(CFA).  The first, with which we are not concerned in this appeal, concerned the scope of BOR4 as a matter of interpretation.  The second question of law was whether BOR4 imposed an absolute duty on the HKSARG to maintain an offence specifically criminalising, amongst other things, forced labour.  The Court answered that question in the negative.  The terms in which it answered the question (at [122] of ZN(CFA)) are highly relevant to the question posed in this appeal and we shall return to that answer in more detail below.

6.In ZN(CFA) at Section D.4, the Court summarised the measures then being taken by the HKSARG to protect BOR4 rights.  In the present case, the Court of Appeal described the current policies and strategies now adopted by the HKSARG to combat human trafficking and forced labour.[4] Since the date of the Court of Appeal’s judgment, and in the light of the remitter of the decisions challenged (as to which see below), those policies and strategies have been further refined as described in the affirmation of Mr Wong Tsz Hin Alvin, an Assistant Secretary for Security of the Security Bureau.[5]

B.      The background facts

7.These proceedings arise in the context of employment of the appellant (whose name has been anonymised in these proceedings as “CB”) as a domestic helper by an elderly man (whose name has similarly been anonymised in these proceedings as “Z”).  For the purposes of this appeal, the relevant background facts can be summarised as follows.

8.CB is a Filipina, now aged in her mid-forties, who came to work in Hong Kong as a foreign domestic helper in 2014.  In 2018, she was looking for a new contract of employment and in response to an advertisement was interviewed by Z and another foreign domestic helper employed by him, Janice, in early September 2018.  CB was engaged, on a trial basis, from 5 September with a view to replacing Janice who was due to leave in November.  CB worked for Z, who is a retired doctor aged in his 80s, from September 2018 until May 2019.  In May 2019, when Z was away from Hong Kong for his annual holiday in France, CB contacted an NGO and made various allegations that she had been subjected to various forms of indecent assault and sexual abuse by Z.  CB resigned her employment at the end of July 2019 and in December 2019 she reported the alleged abuse to the police.

9.The police took statements from CB detailing three forms of sexual abuse complained of, namely: (1) an indecent assault in the form of an invasive body check at the beginning of her employment; (2) requests to masturbate Z during morning massage sessions which CB had to give Z; and (3) requests to watch obscene videos with Z which showed him and Janice engaged in sexual activity. CB provided the police with photos and videos of her and other foreign domestic helpers, including Janice and a woman named Chris engaging in sex acts with Z.

10.As recorded by the Judge below, the police properly took CB’s complaints of sexual abuse or indecent assault seriously.  Their investigation led to Z being charged with two counts of indecent assault in respect of CB’s complaints.  Z was (on 2 July 2021) initially convicted of these charges by a magistrate and sentenced to a total of 30 months’ imprisonment[6] but his convictions were (on 29 April 2022)[7] subsequently quashed and he was re-tried.  Following his re-trial in November 2022,[8] Z was acquitted (on 14 December 2022) because the magistrate had doubts about CB’s evidence.

11.In terms of the chronology of the judicial review leading to this appeal, it is relevant to note that Z had been convicted as at the date of the judgment in the Court of First Instance (22 April 2022) and the setting aside of those convictions only occurred subsequently.  By the time of the Court of Appeal’s judgment in this matter (22 February 2024), Z’s convictions had been quashed and he had been acquitted on re-trial.

12.After the Court of Appeal’s judgment was handed down, a civil action by CB against Z seeking tortious damages for the indecent assaults was dismissed after trial (on 23 July 2024).[9] The trial judge refused leave to appeal to the Court of Appeal (on 14 February 2025)[10] and that application has been renewed (by summons dated 28 February 2025)[11] before the Court of Appeal but is yet to be heard.

C.      Procedural history

C.1    The Court of First Instance

13.The target of these judicial review proceedings were the decisions by the police in the course of their investigation that CB was not the victim of trafficking in persons or forced labour.  The grounds of application for judicial review were both procedural, concerning the police’s investigation process into CB’s case, and also systemic, based on the contention that the breaches of investigative duty under BOR4 were the result of the absence of a bespoke offence criminalising forced labour.

14.As noted above, the judicial review was heard by Coleman J (in March 2022) after Z had been convicted of indecent assault but before those convictions were quashed on appeal.  The judge gave his judgment on 22 April 2022.  In his judgment, Coleman J found various errors in the investigation process by the police.  These findings were upheld by the Court of Appeal and are not challenged by the respondents.

15.In summary, the failures found by the judge were that the officer-in-charge: (1) misdirected himself on the correct legal position as to what constitutes trafficking in persons;[12] (2) adopted irrational reasoning as to why the videos of Janice and Chris did not show they did not consent because of their appearing not to be scared or disgusted;[13] (3) irrationally considered a letter written by Janice was exculpatory of Z in the absence of an interview with her;[14] (4) irrationally considered there was nothing to investigate in relation to Chris or Z’s other new foreign domestic helper because they had not complained;[15] and (5) took irrelevant matters into account in giving weight to the fact CB never complained of being subjected to forced labour, her performance of normal duties of a foreign domestic helper and her ability to resign from employment.[16]

16.Consequently, Coleman J concluded that the judicial review of the police decisions was made out in that the errors amounted to breaches of CB’s rights under BOR4.[17] By way of relief, the learned judge quashed those decisions and remitted them to the Commissioner of Police for renewed consideration, such consideration to include consideration of other possible unlawful acts by Z, besides those for which he had already been convicted, including as regards his other foreign domestic helpers.[18]

17.Separately, and directly relevant to this appeal, Coleman J went on to consider the need for a bespoke offence of forced labour.  He began his analysis by saying, at [210]:

“On the basis that I have found a breach of BOR4 duties owed to CB, the question then arises as to whether the breach is attributable to – that is, there is a causal connection with – a lack of specific legislation in Hong Kong addressing forced or compulsory labour as a particular form of criminality.”

18.Coleman J concluded, at [226], “that the absence of bespoke criminal legislation on forced labour did substantially contribute to the investigative and evaluative failures in CB’s case” and, at [262], “the facts of the CB case do establish the ‘causal connection’ between the particular failures in the case and the lack of a bespoke criminal offence.”

19.Accordingly, the learned judge granted a declaration that the failures as regards the investigation as to whether CB was a victim of trafficking in persons and/or forced labour in this case were causally connected to the absence of specific legislation criminalising forced labour.[19]

C.2    The Court of Appeal     

20.The respondents appealed against Coleman J’s judgment challenging both the finding that there had been breaches of CB’s rights under BOR4(3) and also the finding that these had been caused by the absence of a bespoke criminal offence of forced labour.

21.As noted above, by the time of the appeal, Z’s convictions had been quashed on appeal and his re-trial had resulted in an acquittal on the charges of indecent assault.  Nevertheless, the Court of Appeal proceeded on the basis that there was no suggestion before them that CB’s evidence was not credible and it was noted it had been accepted by the police as being at least prima facie credible since it led to the prosecution of Z.[20]

22.The respondents challenged the CFI Judgment in three respects.[21] First, it was contended that CB’s allegations were not capable of giving rise to trafficking in persons or to forced labour.  It is unnecessary, for the purposes of this appeal, to discuss the arguments advanced on these points in any detail.  The Court of Appeal rejected the respondents’ contentions that, taken at their highest, CB’s allegations did not disclose a possible case of human trafficking[22] or were not capable of giving rise to forced labour.[23]

23.The respondents’ second ground of appeal against the CFI Judgment was a challenge to the learned judge’s finding that there had been a breach of the obligation under BOR4(3) to investigate.  The Court of Appeal concluded that, even after allowing for the wide margin of discretion to the authorities, there had been public law errors in respect of the investigation into whether CB was a victim of trafficking in persons or forced labour.  The Court of Appeal concluded that the learned judge was correct in finding that there had been investigative errors and that his orders quashing the decisions that CB was neither a victim of trafficking in persons nor a victim of forced labour were justified.[24] This conclusion is not challenged by the respondents in this Court.

24.The third ground of appeal in the Court of Appeal, and the point giving rise to the appeal to this Court, concerned the question of whether the investigative failures found were causally connected to the absence of specific legislation criminalising forced labour.

25.The Court of Appeal examined that question by reference to the test of whether the enactment of a specific criminal offence to penalise forced labour was “the only effective solution” to the breaches of BOR4 involved.  They reached a different conclusion to the learned judge for two main reasons.[25] First, the Court of Appeal considered the judge had not applied the correct approach on causal connection but had instead asked (at CFI Judgment [226]) whether the absence of bespoke criminal legislation on forced labour “did substantially contribute” to the investigative failures in this case, which the Court of Appeal described as “a potentially confusing way in which to formulate the required connection”.  Secondly, the Court of Appeal thought the learned judge took into account general and hypothetical shortcomings in the existing system and how they might be remedied, rather than focusing on the actual breaches of BOR4 in the present case.

26.For these reasons, the Court of Appeal allowed the respondents’ appeal to the extent that it had not been demonstrated that the failures in the discharge of the HKSARG’s investigative duties in relation to CB were causally connected with the absence of a specific offence of forced labour.[26] The declaration made by the learned judge was therefore set aside.

C.3    Leave to appeal to the Court of Final Appeal

27.CB applied for leave to appeal to the Court of Final Appeal against the Court of Appeal’s judgment in respect of six questions of law, the first of which was:

“1. Whether the failures identified by the Court of First Instance and affirmed by the Court of Appeal regarding the investigation of whether CB was a victim of forced labour were causally connected to the absence of specific legislation criminalizing forced labour, such as to require the Hong Kong SAR Government (‘HKSARG’) to enact a bespoke offence specifically targeting forced labour in fulfilment of its obligations under Article 4(3) of the Hong Kong Bill of Rights (‘BOR4’)”.

28.The Court of Appeal granted CB leave to appeal on Question 1, holding that the question was of sufficient general importance to warrant leave to appeal being granted and that it was reasonably arguable and noted that it was a question on which they had disagreed with the judge below.[27]

D.      This appeal

D.1    CB’s main contention on this appeal

29.On appeal to this Court, CB seeks to challenge the approach of the Court of Appeal to the causal test, in the context of BOR4 and the HKSARG’s constitutional duty to ensure practical and effective protection of BOR4 rights.  She contends that the correct test is one of substantial causal contribution,taking into account whether the failures in the case may be reasonably and realistically explained by the absence of a specific offence, and not one of an “only effective solution”.  Here, CB contends, the absence of a specific forced labour offence substantially contributed to the investigative failures in the case and that, in order to fulfil its positive obligations under BOR4, the HKSARG must now enact a specific criminal offence.[28]

D.2    A preliminary objection to CB’s case

30.In the respondents’ printed case, an objection to the challenge to the “only effective solution” test of causation is raised on the basis of Flywin Co Ltd v Strong & Associates Ltd (2002) 5 HKCFAR 356.[29] Specifically, it is contended that the argument as to the test of causation had been raised for the first time when leave to appeal was sought from the Court of Appeal and that it has therefore not been considered on intermediate appeal.

31.Further, it is contended on behalf of the respondents that this point is objectionable for the additional reason that leave to argue it had been refused by the Court of Appeal and, since CB did not renew her application for leave to appeal in this regard, she should not be permitted to advance it: Hong Kong Island Development Ltd v World Food Fair Ltd & Anor (2006) 9 HKCFAR 162 at [16]-[21].

32.Questions 2 and 3 for which CB sought leave to appeal from the Court of Appeal were in the following terms:

“2. In considering whether there is a need to enact a bespoke criminal offence under BOR4, and whether the HKSARG has discharged its positive obligation to provide practical and effective protection to victims or potential victims of forced labour, must the court in addition to inquiring whether the breach of BOR4 was causally connected to the absence of a bespoke criminal offence also be satisfied that a bespoke offence is the ‘only effective solution’ to the problems or failures identified by the court in respect of a given case.

3. Assuming Question 2 is answered in the affirmative, on a correct understanding of the positive constitutional require[ment]s of BOR4:

(1) What is the proper approach, and what are the relevant factors, in determining whether a bespoke offence is the ‘only effective solution’? In particular, should a form of proportionality analysis be adopted, having regard to and weighing factors such as (a) the nature and severity of the case-specific failings identified; (b) the likelihood of similar failings recurring in the Hong Kong context absent bespoke legislation; (c) the extent of causal connection and contribution as between the lack of bespoke legislation and the identified failings; and (d) any evidence from the HKSARG on the extent to which, notwithstanding the acknowledged benefits of a bespoke approach, it would be detrimental to the overall public interest or unworkable to specifically legislate on the matter.

(2) Who bears the burden of proof with regard to the question of bespoke legislation in showing systemic compliance or non-compliance”.

33.In refusing leave to appeal on those questions, the Court of Appeal said:

“We do not give leave on Questions 2 to 5. They seem to us to be merely arguments or approaches that may be relevant to Question 1. Further, Questions 2 and 3 raise new arguments not run before this court. There was no suggestion before us that ‘the only effective solution’ approach outlined in Cheung CJHC’s judgment in ZN(CA) at §168 was defective, inadequate or inapplicable. Nor was there any argument before us that a proportionality analysis should be applied to the question of causation. Whether CB should be permitted to run these arguments will be a matter for the Court of Final Appeal.”[30]

34.We are satisfied that CB’s challenge to the “only effective solution” test for causation in this context is properly raised in this appeal as part of the scope of Question 1.  As noted above, Coleman J did apply a substantial contribution threshold to the question of whether the absence of a bespoke criminal offence of forced labour led to the investigative failures in this case.  That approach was held by the Court of Appeal to be wrong and “a potentially confusing way in which to formulate the required connection”.  They concluded that the learned judge should instead have adopted the “only effective solution” approach to causal connection.  We therefore question, with respect, the Court of Appeal’s view, in refusing leave to appeal, that there was no suggestion that the “only effective solution” approach was inapplicable.

35.In any event, the point raises an important question of law and has been fully argued before us.  Furthermore, as the Court of Appeal themselves recognised, there is some overlap between the questions for which leave was refused and Question 1 for which leave was granted.

36.Further, we would accept that the appeal is not rendered academic by the procedural history of the criminal prosecution of Z, which has been finally determined, and of the civil action brought by CB against Z in the District Court, the dismissal of which is subject to an application for leave to appeal to the Court of Appeal.  As noted above, the Court of Appeal proceeded on the basis that there was no suggestion before them that CB’s evidence was not credible and that it had been accepted by the police as being at least prima facie credible so that it was a live question for the courts below to consider whether, in the light of that evidence, CB’s rights under BOR4 had been complied with.  This approach remains appropriate as matters stand in this Court, both in relation to the criminal prosecution of Z and also the civil action brought by CB in the District Court.  However, it is right to note that, if the civil claim remains dismissed, it is difficult to see how CB’s BOR4 rights could be said to have been prejudiced in this case by any investigative failures.

E.      Addressing Question 1

E.1    The context of the question

37.It was common ground between the parties to this appeal that the proper test of causation in any given case depends on the context and purpose for which the question is asked.[31] The starting point for identifying the correct context for the causation inquiry in the present case is the positive duty imposed on the HKSARG under BOR4.  That duty was held by this Court, in ZN(CFA), to be one “to have in place measures providing practical and effective protection against the activities prohibited under BOR4”.[32]  As the Court went on to hold:

“Since … the touchstone is whether the protection of the rights under BOR4 is practical and effective, the decision as to how to achieve such protection must necessarily be a matter for the HKSARG, subject, of course, to the supervision of the courts to assess the practical efficacy of the measures adopted.”[33]

38.More specifically, in the context of BOR4, the positive duties imposed are to be distinguished between their substantive and procedural aspects.  As the European Court of Human Rights (“ECtHR”) explained in SM v Croatia (2021) 72 EHRR 1:

“It follows from the above that the general framework of positive obligations under art.4 includes: (1) the duty to put in place a legislative and administrative framework to prohibit and punish trafficking; (2) the duty, in certain circumstances, to take operational measures to protect victims, or potential victims, of trafficking; and (3) a procedural obligation to investigate situations of potential trafficking. In general, the first two aspects of the positive obligations can be denoted as substantive, whereas the third aspect designates the States’ (positive) procedural obligation.”[34]

39.This distinction between the substantive and procedural aspects is of significance.  Whereas the substantive aspects of the positive obligations look at the end results of a finding of prohibited conduct (whether it be trafficking or forced labour), the procedural aspect is different.  As the ECtHR went on to explain in the same case:

“The procedural obligation is a requirement of means and not of results. There is no absolute right to obtain the prosecution or conviction of any particular person where there were no culpable failures in seeking to hold perpetrators of criminal offences accountable. Thus, the fact that an investigation ends without concrete, or with only limited, results is not indicative of any failings as such. Moreover, the procedural obligation must not be interpreted in such a way as to impose an impossible or disproportionate burden on the authorities.”[35]

E.2    The causation exercise when there is a breach of BOR4

40.The causation exercise arises where a breach of BOR4 is identified.  The nature of the breach is a fact-sensitive matter.  The remedy that must then be adopted, in order to comply with the duty to provide practical and effective protection of the rights under BOR4, will depend on the nature of the detected failure.  There may be more than one potential remedy, in which case the HKSARG is afforded a wide margin of discretion in deciding how to address the failure found.  Taking this approach, it is legitimate to ask if the enactment of specific legislation criminalising forced labour is the remedy that must be adopted in the present case.

41.This was the approach adopted in ZN(CFA) and ZN(CA) when considering whether it was shown that bespoke legislation criminalising forced labour was necessary for the HKSARG to comply with its obligations under BOR4 or whether a patchwork of existing offences was sufficient (Question 2 before this Court in ZN(CFA)).[36]

42.Thus, as a matter of substance, in this Court, it was held:

“… I would reject the appellant’s contention that BOR4 necessarily requires the HKSARG to enact a bespoke offence criminalising forced or compulsory labour (although, as will be seen, this may be demonstrated to be necessary if the measures adopted by the HKSARG are shown not to afford practical and effective protection of BOR4 rights).”[37]

“… the relevant inquiry is whether, on the facts of any given case, the protection of the rights under the ECHR or, in our case, the BOR has been rendered ‘practical and effective’.”[38]

“Focusing on the obligation to protect against the requirement to perform forced or compulsory labour, it also cannot be said that the patchwork of offences available to the HKSARG is inadequate to provide practical and effective protection of that BOR4 right. The argument to the contrary advanced on behalf of the appellant was one of form over substance. It simply could not be shown that, had there been a bespoke offence prohibiting forced or compulsory labour, the appellant would have been better protected against the gross mistreatment to which he was subjected by his employer.”[39]

43.This is consistent with the approach taken in ZN(CA).  There, it was held:

“… The patchwork or adaptive approach may be ineffective …, the ineffectiveness may be due to a number of possible reasons or a combination of them. It is a quantum leap to say that because the existing measures are ineffective, therefore there must be a specific criminal offence enacted to combat forced labour. There has to be established a causal connection between the ineffectiveness and the lack of a specific criminal offence.”[40]

“Would the enactment of a specific offence to penalise forced labour help? The answer is of course it would, to some extent. But, that is not the crucial question we have to ask and answer. For, unless the enactment of a specific criminal offence to penalise forced labour is the only effective solution to the problem I have just identified, one just cannot conclude from the fact that the existing measures are ineffective that, therefore, there must be enacted a specific criminal offence. That would be a non sequitur.”[41]

44.As already noted in the Introduction to this judgment, in ZN(CFA) at Section D.4, this Court referred to the approximately 50 potentially applicable offences already in place and the administrative framework that had been developed and was being operated by various governmental agencies to ensure protection of BOR4 rights.  On the basis of that patchwork of offences and administrative framework, the Court rejected the need for bespoke legislation criminalising forced labour holding, in substance, that the identified failures in that case did not require the remedy of the enactment of specific legislation by the HKSARG and that the necessary protection of BOR4 rights could be achieved by the patchwork of existing offences and administrative framework, deficiencies in which could be enhanced by, for example, better training of personnel and improved inter-departmental co-operation and collaboration.

45.Thus, in answering Question 2 in ZN(CFA), this Court held:

“(1) The HKSARG has a wide margin of discretion in the manner in which it complies with its positive obligations under BOR4 and there is no absolute duty on the HKSARG to maintain an offence specifically criminalising forced or compulsory labour.

(2) To comply with its obligations in respect of BOR4, the HKSARG must take steps to afford practical and effective protection of those rights. Whether practical and effective protection has been provided will depend on the facts of any given case.

(3) On the facts of this case, it has not been shown that a bespoke offence criminalising forced or compulsory labour is necessary in that the patchwork of offences already in existence failed to afford the appellant sufficient protection.

(4) The determination that a bespoke offence is not required does not preclude a different conclusion being reached in a future case, in the event that the HKSARG is shown in future not to afford practical and effective protection of the rights under BOR4 by reason of the absence of such an offence. Nor should this judgment be taken to indicate that a patchwork of offences would necessarily be sufficient to address a prohibition on human trafficking, if the HKSARG were under a constitutional duty to prohibit that activity.”[42]

46.It is therefore clear that the approach adopted in ZN(CFA) and ZN(CA) was a fact-specific remedy-based approach, focusing on the specific finding as to breach of BOR4 in the given case and asking if, in consequence, those rights could be given practical and effective protection by some means other than bespoke legislation criminalising forced labour.

47.It is true that in ZN(CFA) and ZN(CA) there are passages that examined whether the absence of bespoke legislation caused the investigative failures that amounted to breach of ZN’s BOR4 rights in that case.[43] This is because the reasons for the failures in a given case may shed light on, or be of particular relevance to, the question of whether such legislation is required to afford the requisite protection.  These reasons may include, depending on the facts, the absence of bespoke legislation.  However, even if the absence of bespoke legislation did contribute to the failures, that cannot be determinative.  The ultimate issue remains whether there exist alternative means capable of providing the necessary and practical protection.  For this reason, the issue in ZN’s case was ultimately decided on the basis of the fact-specific remedy-based approach to causation we have described above.  On the “only effective solution” basis, this Court agreed with the Court of Appeal and concluded that specific legislation criminalising forced labour was not required in order to address the breaches of BOR4 in that case.

48.That, in our view, is the appropriate and consistent approach that should be taken as regards causation in this or any other case concerning the HKSARG’s compliance with its positive duties under BOR4.

E.3    The causation approach in this case

49.CB’s case on this appeal is summarised in Section D.1 above.  That approach looks at causation prior to the breach of BOR4(3) and not as a remedy for that breach.  It argues that the Court of Appeal erred in adopting the “only effective solution” approach.  Instead, relying on various cases concerning the interpretation of the ECHR, Ms Monica Carss-Frisk KC, appearing for CB, advocated a test of substantial contribution or connection[44] and contended that “[the] investigative failures in this case are marked by a misdirected focus and inability to identify key elements and indicia of forced labour” which would have been prevented had there been a bespoke offence criminalising forced labour.  It is contended on behalf of CB that in assessing whether the HKSARG should be required to enact a bespoke offence in order to protect BOR4 rights, there is little or no room for a margin of discretion since it has not been argued for the HKSARG that it would be burdensome for it to so legislate.  Relying on the dictum in ZN(CA) that added the reservation regarding future developments “when more and more cases should come before the courts demonstrating to us that whatever measures (short of a specific criminal offence) that the government may have put in place, they are not effective enough”,[45] it is argued that the HKSARG must now enact a specific criminal offence.[46]

50.We do not agree that this is the appropriate approach.  For the reasons set out in Section E.2 above, we consider the “only effective solution” approach is the correct way in which to determine if, in the event of a breach of BOR4 rights, the appropriate remedy is to require the enactment of bespoke legislation criminalising forced labour.

51.This was the approach adopted by the Court of Appeal in the present case.  Applying the fact-specific remedy-based approach in ZN(CFA) and ZN(CA), the Court of Appeal held:

“In other words, the question is not whether the breaches found would not have occurred if there had been a bespoke offence of forced labour. A simple ‘but for’ connection is not sufficient, because if the victim’s rights could also have been protected effectively in other ways, it was for the Government to decide which way to adopt, and the court would have no basis to hold that a specific offence was required. Instead, it is necessary to show that enacting a specific offence is ‘the only effective solution’ – a sine qua non of compliance. Of course the question must be approached not on the theoretical plane, but with realism and common sense.”[47]

52.With this approach in mind, which is what we had in mind in ZN’s case when we referred to the possibility of future cases arising which might demonstrate the need to enact bespoke legislation,[48] we now turn to address the substantive question raised in this appeal, namely whether the investigative breaches in the present case lead to the conclusion that the HKSARG should be required specifically to legislate to criminalise forced labour.

E.4    Is a bespoke offence required to provide practical and effective protection of BOR4 rights?

53.As this Court noted in ZN(CFA), it is necessary to keep in focus the findings as to breach of BOR4 in asking the question of whether bespoke legislation criminalising forced labour is required in order for the HKSARG to discharge its positive obligations under BOR4.[49]

54.In the present case, the Court of Appeal adhered to that need in approaching the question of the need for bespoke legislation to remedy the BOR4 breaches here, holding:

“Another point that needs to be emphasised is that the exercise must be grounded on the facts of the case. In particular, … it is necessary to keep in focus the findings as to the breaches of BOR 4 in the case. In adjudicating on this point, the court is not concerned with whether certain potential deficiencies that one can conceive of in the existing system may best be rectified by the enactment of a bespoke offence. It is concerned with the question whether the breaches of duty under BOR 4 found in the case were caused by – in the sense explained above – the absence of a bespoke offence criminalising forced labour.”[50]

55.This reflects the point made above that the procedural investigative duty under BOR4 is an obligation of means and not results and should not be interpreted so as to impose a disproportionate burden on the HKSARG.

56.In the present case, Coleman J found that there were investigative failures in respect of the police’s handling of CB’s case, which were upheld by the Court of Appeal.  These are summarised at [15] above.  These findings are somewhat surprising in view of the learned judge’s acknowledgment that, from the start, the police properly took CB’s complaints of sexual abuse or indecent assault seriously.[51] The Court of Appeal similarly commended the police for their response to CB’s complaints, observing:

“In fairness to the Police, it is right to record, as the judge also acknowledged, that they took CB’s report first made on 13 December 2019 very seriously, followed the steps set out in the HQO, and acted with promptitude in response. A statement was immediately taken from CB on 13 December; Z was arrested, his house was searched under a warrant and a cautioned statement was taken from him on 16 December; a second statement was taken from CB on 17 December; and a third statement was taken from CB and Z was twice interviewed under caution not long afterwards. Had CB still been working in Z’s house at the time, the Police’s actions would have put a stop to any continuing abuse. The investigation eventually led to a prosecution and initial conviction. For all of this, CB for her part said she was grateful.”[52]

57.As the Court of Appeal recorded, the investigations undertaken led to Z’s prosecution and, initially at least, his conviction of two charges of indecent assault.  Importantly, as the Court of Appeal also recorded, the investigation would, if CB had still been working in Z’s home at the time, have put a stop to any continuing abuse.

58.It is therefore appropriate to ask what were thought to be the investigative failures said to constitute breaches of the HKSARG’s BOR4 obligations here.  Coleman J held that there was a failure to investigate Z’s sexual conduct in relation to other foreign domestic helpers:

“Apparently no, or very little, investigation was conducted against the abuses which CB says might have been practised on Z’s other FDHs. The lack of further investigation along this direction is central to CB’s case. The other FDHs named by CB include Janice, Chris, the women shown in the photo album a page of which she took a picture, and Z’s FDH succeeding CB (‘New FDH’).”[53]

59.The learned judge expanded on his criticism of the officer-in-charge of the investigation in the following terms:

“… there seems to have been a complete failure to take into account the facts and chronology which identified:

(1) there was video evidence of Z engaging in sexual acts with his previous FDHs, including Janice;

(2) CB was recruited specifically to replace Janice (and they overlapped in employment for a short period);

(3) CB was first sexually assaulted almost immediately after recruitment, under the very pretence that it was part of the recruitment process;

(4) CB was later (routinely) sexually assaulted commencing immediately after Janice had left Z’s employment;

(5) the nature of the sexual assaults on CB was similar to the nature of the sexual acts involving Z and Janice prior to her departure from employment, as shown on the videos;

(6) there is no necessity for there to have been any larger or more organised scale of activity for there to have been at least a credible suspicion of trafficking, but in any event there was some demonstration of a larger and more organised scale of activity;

(7) in so far as it might be thought necessary (which it probably is not) for there to have been some monetary or commercial gain, Z was clearly obtaining sexual services at no cost and for which he would otherwise have had to pay someone else.”[54]

60.Finally, in granting relief, the learned judge made it clear that the remitter was directed at the failure to conduct these investigations since the relief included the following orders, namely:

“(3) The questions as to whether CB was a victim of TIP and/or forced labour are remitted to the Commissioner of Police for renewed consideration.

(4) For the avoidance of doubt, the renewed consideration directed in paragraph (3) above shall include consideration as to other possible unlawful acts by Z (besides those which he has already been convicted) including as regards his other FDHs.”[55]

61.The Court of Appeal upheld Coleman J’s conclusion that the failure to investigate Z’s conduct as regards the other foreign domestic helpers constituted investigative failures which breached the HKSARG authorities’ BOR4 duties.  Those conclusions of the courts below are not subject to appeal and are thus no longer matters in issue in the case.  However, it is difficult to see how such failures amounted to breaches of CB’s BOR4 rights.

62.On the law as it stands, it is not clear how, in pursuing the charges brought against Z alleging indecent assault of CB, it could have been relevant to introduce allegations concerning Z’s conduct in respect of other alleged victims.  If evidence resulting from such investigations was not relevant to CB’s case, one may ask where instead such investigations might have led?  It is possible they would have resulted in other indecent assault charges being brought against Z but these would have been irrelevant to the case concerning CB and her BOR4 rights and would not have promoted a finding of forced labour.

63.This seems to have been recognised by the learned judge who said:

“In CB’s case, the only potential charge to be brought against Z was one of sexual assault. It is not surprising, therefore, that the investigation was focused on the possibility of charging and proving such a crime. That is why Mr Pao was able – in fact, constrained – to make the submission that any further investigation as might have been conducted by the Police would have made no material difference to CB or to the criminal charges preferred against Z. It is also why Mr Wan (in evidence) and Mr Pao (in submission) were able to state that the prosecutor was correct to have told the Magistrate at Z’s trial that the videos – showing Z engaged in sexual acts with other FDHs – were irrelevant to the charges laid against Z. Indeed, even if Mr Wan had believed that the videos did demonstrate non-consensual sexual acts performed by the former FDHs at Z’s instructions, the videos would have been irrelevant to the charges laid against Z in respect of the sexual assaults committed by him on CB.”[56]

64.These observations were apposite.  As we have emphasised, and as was emphasised in ZN(CFA), one must keep in focus the finding of breach of BOR4 in asking the question of what remedy is required in any given case. Here, the breaches of BOR4 found were of the investigative duties owed to CB. Her complaints were assessed as constituting allegations of indecent assault and Z was duly prosecuted for that offence.  There was some suggestion (see the passages from the CFI Judgment at [177] quoted above) that these indecent assaults of CB might have formed part of a pattern of forced labour for sexual exploitation maintained by Z.  But even if that were so, there is no suggestion that this would have affected the prosecution of Z arising from CB’s complaints.  The conduct being part of a pattern of abuse might have been relied upon as an aggravating factor in sentencing Z for indecent assault of CB.  Indeed, the magistrate who convicted Z initially did reflect the fact of Z’s breach of trust in his capacity as CB’s employer in imposing the sentence he did.[57]

65.Similarly, there seems to have been some suggestion in Coleman J’s judgment that a more nuanced approach to the issue of consent might have been justified in the context of forced labour which would have been different to conventional sexual offences.[58]

66.However, the difficulty with this argument is that, on the facts of CB’s case, there is no basis for suggesting that to protect her BOR4 rights an alternative criminal charge should have been available but was, in breach of those rights, lacking.

67.As the Court of Appeal stated:

“It has not been articulated concretely just how the existing system with a patchwork of available offences failed or would fail to afford CB practical and effective protection on the facts of her case. The closest Mr Chan gets to this is when he submits that the laws on forced labour stress the dangers of conventional notions of consent compared with broader considerations appropriate to the question of forced labour. But the fact before the judge was that CB’s consent was found lacking and Z was convicted and sentenced.”[59]

“We are aware that the conviction was subsequently set aside and Z was acquitted on the re-trial, but this occurred after the Judgment. No respondent’s notice has been filed on CB’s behalf in this appeal to contend that the fact that Z was ultimately acquitted means that there was a breach of BOR 4 duties, or that he would have been convicted of a forced labour offence (if it existed) on the same evidence even though he was acquitted of the sexual offences. Nor has any argument been advanced before us to contend that Z’s subsequent acquittal reveals a deficiency in the available criminal law such as was found in Siliadin (see below) or demonstrates a failure by the Government to discharge its positive obligation under BOR 4 to prosecute and penalise effectively the conduct CB complained of. At the end of his submissions Mr Chan has made a veiled criticism of one of the reasons given by the second magistrate in acquitting Z, but there was no argument properly advanced that Z would probably have been convicted by the magistrate of a forced labour offence if it had existed.”[60]

68.In the absence of any suggestion that Z could or should have been convicted of a forced labour offence if it had existed, notwithstanding his acquittal of the charges of indecent assault, we can see no room to argue in this case that the only effective solution to provide practical and effective protection of CB’s BOR4 rights is by the enactment of bespoke legislation to criminalise forced labour.

F.      Conclusion and disposition

69.For the above reasons, we would answer the question for which leave to appeal was granted in the negative.  It has not been shown that the enactment of bespoke legislation criminalising forced labour is required as the only effective solution to provide a remedy for the breaches of CB’s BOR4 rights as found by the courts below.  Nor do those investigative failures as found demonstrate that such legislation is required to provide practical and effective protection of CB’s BOR4 rights.

70.Accordingly, in light of that answer, we would dismiss this appeal and affirm the Court of Appeal’s judgment setting aside the learned judge’s declaration.  We would add that the form of the declaration made in any event begged the question of whether the HKSARG was in breach of its obligations under BOR4 in having failed to enact specific legislation criminalising forced labour: cf., in this context, the order of this Court in Sham Tsz Kit v Secretary for Justice (2023) 26 HKCFAR 385 at [260(b)(ii)] and Sham Tsz Kit v Secretary for Justice (No 2) (2023) 26 HKCFAR 478 at [5]-[10].

71.We would also make an order nisi that the appellant pay the costs of the appeal to this Court to the respondents, the parties being at liberty to lodge written submissions regarding such costs within 21 days of the date of this judgment, to be dealt with on the papers.

Mr Justice Ribeiro PJ:

72.I agree with the joint judgment of the Chief Justice and Mr Justice Fok PJ.

Mr Justice Lam PJ:

73.I agree with the joint judgment of the Chief Justice and Mr Justice Fok PJ.

Mr Justice Gummow NPJ:

74.I agree with the joint judgment of the Chief Justice and Mr Justice Fok PJ.

Chief Justice Cheung:

75.The appeal is accordingly unanimously dismissed with costs as indicated in paragraph 71 above.

Ms Monica Carss-Frisk KC, Mr Abraham Chan SC, Mr Albert NB Wong and Mr Alvin Cheung (on a pro bono basis), instructed by Patricia Ho & Associates, assigned by the Director of Legal Aid, for the Appellant

Lord Pannick KC, Mr Jin Pao SC, Mr Martin Ho and Ms Celeste Chan, instructed by the Department of Justice, for the 1^st to 3^rd Respondents