In the recent case of Huang v Zheng,(1) the High Court considered whether to issue a letter of request to the courts of mainland China to take evidence from the defendant in the mainland, including his cross-examination by video conferencing, for the purpose of civil proceedings in Hong Kong. In deciding whether to issue a letter of request, the Court must have regard to the mutual arrangement for taking evidence in civil proceedings between the courts of both jurisdictions. Article 6 of the mutual arrangement provides for the scope of assistance that may be requested by the courts of each jurisdiction. In respect of a request made by the Hong Kong courts to the mainland courts, pursuant to the arrangement, obtaining evidence is limited to taking statements from witnesses, providing documentary evidence (and the like) and conducting site examinations – such a request does not extend to a request for the cross-examination of a witness, even where the process of obtaining evidence could be conducted by video conferencing.


The civil proceedings between the plaintiff and the defendant arose out of a dispute concerning the sale of property pursuant to a sale and purchase agreement dated 29 January 2015. The defendant alleged that he had signed the agreement (as vendor) under duress. The case is set down for trial (for three days) in November 2022. Since December 2016, the defendant has apparently been detained in mainland China and, following his conviction, been imprisoned there.

Given his predicament, the defendant applied to the Court of First Instance of the High Court in Hong Kong for a letter of request to be issued to the mainland courts allowing his evidence by cross-examination to be taken from prison. While he had already prepared a witness statement for the purpose of giving evidence in the Hong Kong proceedings, he was not able to come to Hong Kong to be cross-examined at the trial. The dispute between the parties is such that their testimony at trial will be important.

An Arrangement on Mutual Taking of Evidence in Civil and Commercial Matters between the Courts of the Mainland and Hong Kong Special Administrative Region (the mutual arrangement) came into force in March 2017 between the two jurisdictions. There are also statutory provisions and procedural rules in Hong Kong that regulate the issue of letters of request to judicial authorities in overseas jurisdictions.(2) These powers and rules existed prior to the mutual arrangement and apply with respect to all jurisdictions, provided that the Hong Kong courts are satisfied that a letter of request complies with Hong Kong law and that the receiving judicial authority will recognise the request and act on it.

However, instances of letters of request between the courts of mainland China and Hong Kong appear to have been few and far between prior to the mutual arrangement. Although the Hague Convention on the Taking of Evidence Abroad in Civil and Commercial Matters (1970) continues to apply to Hong Kong after reunification in 1997, it does not apply as between the mainland and Hong Kong, hence the need for the mutual arrangement in civil proceedings.

Two principal issues arose for the Court's consideration.

First, whether (based on the parties' expert evidence) the Court could conclude that it was permissible to take evidence from a prisoner in mainland China for the purpose of a civil action in Hong Kong – the Court was not concerned with principles of mutual assistance in criminal matters.

Second, for the purpose of taking evidence pursuant to the mutual arrangement, whether it was permissible to conduct a cross-examination of the defendant in the mainland.

With respect to these issues, the parties submitted expert reports on mainland law.


The Court dismissed the defendant's application for the issuance of a letter of request to the judicial authority of mainland China. Although the Court should consider its powers under the court rules, the judge noted that the mutual arrangement governed the issuance of letters of request made after it came into force.

Taking of evidence from prisoner in mainland China
The Court noted that the defendant was the key witness for the defence and his detention since December 2016 prevented him from leaving mainland China. In the circumstances, he had made genuine attempts to defend the proceedings in Hong Kong and any delay on his part in applying for a letter of request should not be held against him because the trial was still approximately one year away.

Based on the parties' expert reports, it appeared that it was generally possible to take evidence from a witness who was a prisoner in mainland China for the purpose of a civil action in Hong Kong. It also appeared to be the case that the process of taking evidence could be conducted by video conferencing, although the defendant would not be able to leave prison even temporarily.

Whether cross-examination of a witness in mainland China is within scope of mutual arrangement
Here, the parties' expert evidence on the provisions of mainland law appears to have differed significantly.

Article 6 of the mutual arrangement (regarding the scope of assistance that may be requested) distinguishes between the requests that can be made by the respective requesting parties. Where a request relating to witness evidence is made by a Hong Kong court, the scope of assistance is limited to taking a statement – it does not extend to the cross-examination of the witness. However, there is no such restriction where the requesting party is the mainland court. The Court contrasted the lack of reciprocity in this regard with the terms of the mutual arrangement for the taking of evidence between mainland China and Macau (both civil law jurisdictions).

The Court rejected the defendant's expert evidence that suggested that there are different types of evidence gathering in mainland China, some of which are (so the argument went) similar to cross-examination, such that cross-examination of a witness in mainland China could be possible in practice. This argument appears to have received short shrift from the Court, which concluded that there is no equivalent process to cross-examination under mainland law as understood by Hong Kong law for the purpose of civil proceedings. The Court stated as follows:

Without disrespect, the Arrangement is one negotiated between Mainland China and Hong Kong. The terminology in the Arrangement indicates that the draftsmen did not intend to introduce, wholesale, all types of evidence under Mainland law where Hong Kong is the requesting party.(3)

Further, the Court noted that article 7 of the mutual arrangement (regarding the manner of the requested party's assistance to the requesting party) could not be invoked to expand the scope of assistance under article 6 – where a request did not come within the scope of assistance of article 6, the procedure set out in article 7 "does not come into play".(4)

The Court dismissed the defendant's application because it did not come within the scope of article 6 of the mutual arrangement.


Based on the wording of article 6 of the mutual arrangement, the Court's decision is understandable. A letter of request by a Hong Kong court with respect to witness evidence, pursuant to article 6, is limited to obtaining statements and does not extend to cross-examination. This is reflected in the deliberate wording of the mutual arrangement. The outcome in the case also highlights the difference between an inquisitorial trial process familiar to civil law systems and an adversarial trial process typical of common law jurisdictions (such as Hong Kong). As regards witness testimony, it is also difficult to envisage how a mainland judicial authority could comply with a letter of request from a Hong Kong court that went further than a request to obtain a statement from an intended witness.

Quite how this leaves the defendant to prepare for trial in Hong Kong is not clear. Given that he appears unable to travel to Hong Kong for the trial in November 2022, he could apply to attend trial by video conferencing facility. However, this is not the norm for civil trials in Hong Kong with respect to key witnesses and, given the defendant's imprisonment in mainland China, he may experience practical difficulties in making himself available for trial by video conferencing facility.

While it is probably of small comfort to the defendant, the Court's decision usefully confirms that as a matter of practice, a comprehensive draft letter of request (in written Chinese where it relates to the mainland courts) should be filed at court together with the applicant's written submissions.(5)

For further information on this topic please contact Antony Sassi, David Smyth or Jennifer Leung at RPC by telephone (+852 2216 7000) or email ([email protected],hk, [email protected] or [email protected]). The RPC website can be accessed at


(1) [2021] HKCFI 3362, 9 November 2021.

(2) Evidence Ordinance (Cap. 8), sections 75-76, and Rules of High Court, Orders 39 and 70.

(3) Supra note 1, at para 31.

(4) Supra note 1, at para 37.

(5) Supra note 1, at para. 43. Hong Kong Civil Procedure (2022), Appendix A, Form No. 35.