Ben Douglas-Jones KC, leading Valeria Swift, 5 KBW, appeared for the Crown in R v Kadir  EWCA Crim 1244, in which the Vice President of the Court of Appeal Criminal Division gave important guidance on live link evidence from abroad. The case specifically considered the use of WhatsApp.
1. A judge has the power to direct a live link via WhatsApp – which is end-to-end encrypted - under S.51, CJA 2003; it is for the judge concerned to make a fact-specific decision in the circumstances of the particular case.
2. The party making the application for a live link direction must provide the judge with all the requisite information.
3. The parties (prosecution or defence) need to give consider and prepare any applications for witnesses to testify from another country via a live link at an early stage of proceedings:
(1) First, s6C of CPIA Act 1996 must be complied with. The requirements apply to a witness who will give evidence in person as well as to a witness who will give evidence via a live link. The failure by a defendant to comply with the requirements where a witness is in another country is likely to give rise to additional difficulties for the prosecution in investigating the proposed witness, and for the court in considering the application. Notice of the identity of the witness affords an opportunity for appropriate investigations to be made. Failure to give notice is an inhibition on the prosecution’s ability effectively to test his evidence; see s.51(6)(f)(ii) [the provision which now applies; post-trial, in June 2022, the statute was amended].
(2) Second, in relation to an application for a live link for a witness who is in another country, it is necessary also to bear in mind the principle that one state should not seek to exercise the powers of its courts within the territory of another state without the permission (on an individual or a general basis) of that other state. It cannot be presumed that all foreign governments are willing to allow their nationals, or others within their jurisdiction, to give evidence before a court in England and Wales via a live link. In some states, it may be necessary for the UK to be asked to issue an International Letter of Request (ILOR) to the state concerned; see the guidance issued by the Lord Chief Justice on 4 July 2022. A failure to make a relevant enquiry causes the judge to lack vital information in deciding whether, in the light of the factors listed in s.51, it is in the interests of justice for a live link direction to be made.
(3) Third, the adequacy of the arrangements needs to be checked in good time.
(4) Fourth, there needs to be sufficient information to enable the judge to assess the risks which might be involved in a witness giving evidence from abroad, including any risk that s/he would be under any form of pressure from any other person. This would include information as to the location from which the witness would be giving evidence.