Divisional Court holds that public inquiries may demand attendance by witnesses based overseas

The Divisional Court (Singh LJ and Jay J) has given judgment in R (UCPI Designated Lawyer Officers Core Participant Group) v Sir John Mitting, sitting as Chairman of the Undercover Policing Inquiry [2026] EWHC 1394 (Admin), holding that the chairman of a public inquiry may issue a notice under section 21 of the Inquiries Act 2005 to individuals outside the territory of the UK requiring them to give oral evidence.

The Undercover Policing Inquiry is investigating undercover policing in England and Wales since 1968. The Inquiry issued a notice under s. 21 to a former police manager known as “HN86”, who was the Detective Chief Inspector in operational charge of the Special Demonstration Squad (a former undercover policing unit in the Metropolitan Police Service) during a period in the 1990s. HN86 has been accused of being overtly racist and of tasking officers to gain intelligence on the family of Stephen Lawrence. He denies these allegations.

The s. 21 notice requires HN86 to attend the Undercover Policing Inquiry to give oral evidence in July 2026. HN86’s place of permanent residence is outside the United Kingdom. Section 35 makes non-compliance with a section 21 notice an offence.

The Claimant, which represents HN86 in the Inquiry, challenged the issue of the notice on two grounds:

• An inquiry chairman does not, in principle, have the power to issue a notice under s. 21 to a person residing overseas as this would offend against the presumption that legislation is not intended to have extraterritorial effect.
• The issuance of the s. 21 notice in this particular case was procedurally unfair.

The Court rejected both grounds.

Ground 1

The Court held that the presumption against extra-territoriality did not arise in respect of the issue of the s. 21 notice, as there was not in substance an exercise of extra-territorial jurisdiction under international law and domestic law principles (§§87-89).

The Court first assessed the principles of jurisdiction in international law, distinguishing between “prescriptive” jurisdiction (described as “the power to make laws, decisions or rules”) and “enforcement” or “adjudicative” jurisdiction (described as “the power to take executive or judicial action in pursuance of or consequent on the making of decisions or rules”) (§60). It noted that, under international law, jurisdiction is generally limited to a state’s territory and a state is not permitted to exercise jurisdiction extra-territorially without some specific basis in international law: §61.

It noted, however, that international law “increasingly recognises” the “effects doctrine”, which is that “there may be circumstances in which a state can legitimately exercise prescriptive jurisdiction over persons and acts taking place outside its territory where those acts have effects within its territory” (§63).

The Court then considered the position in domestic law. The Court considered it had to decide whether Parliament intended that the “package of provisions” (which includes both s. 21 and s. 35) to “be applicable in circumstances such as the present, where HN86 resides outside the territory of the UK” (§80).

In finding that Parliament did intend the package of provisions to be applicable, the Court relied on a line of authority in criminal law starting with Treacy v Director of Public Prosecutions [1971] AC 537 (“Treacy”) and running through to R v Sheppard & Anr [2010] EWCA Crim 65 (“Sheppard”). It considered that the House of Lords in Treacy recognised the “effects doctrine” in domestic law (§71) and had seen “no reason in comity to prevent Parliament from rendering liable to punishment, if they subsequently come to England, persons who have done outside the UK physical acts which have had harmful consequences on victims in England” (§74).The Court saw “no reason in principle” why this reasoning should not also apply to an omission (like an offence contrary to s. 35) that takes place outside the territory of the UK but has consequences here (§75).

In Sheppard, applying this line of case law, the Court of Appeal applied a test that asks where the “substantial measure” of the conduct of an offence takes place.

Applying those principles to this case, the Court held that “what is critical is that the witness is required to be in the UK on a certain date at a certain time” (§85). The Court went on to state that “the fact that the witness happens to be resident in another country outside the UK does not alter the nature of that offence of omission at that time and place” (§86).

This led the Court to conclude that the issuing of a s. 21 notice was not in substance an exercise of extra-territorial jurisdiction, because “the offence, or at least a substantial part of it, takes place in the territory of the UK: where there should be a witness, there is an empty chair” (§87).

Notably, the fact HN86 was a British citizen was “not the, or even a, crucial factor” in the Court’s analysis (§104(iv)).

Ground 2

Overall, the Court found that the Defendant had not acted unfairly (§114).

First, approving the decision of the High Court of Justice in Northern Ireland The Muckamore Abbey Hospital Inquiry case [2023] NIKB 107, the Court held that fairness did not demand that a witness be given advance notice of an Inquiry’s intention to issue a s. 21 notice should the need arise, and that there were a number of public policy reasons militating to the contrary (§112).

Second, the Court accepted the Inquiry’s submission that no legitimate expectation arose as no clear, unambiguous and unqualified statement made or practice adopted by the Defendant which might satisfy this principle had been identified by the Claimant (§113).

Fiona Scolding KC and Charles Bishop were instructed by the Inquiry Legal Team for the successful Defendant. Carine Patry KC also acted for the Defendant at an earlier stage in proceedings.