Policing Disclosure: R (Ansari) v Chief Constable of North Wales Police
24 March 2026
By Kian Leong Tan
INTRODUCTION
In R (Ansari) v Chief Constable of North Wales Police [2026] EWHC 472 (Admin), the High Court (Chamberlain J) held that the heightened level of disclosure required under Secretary of State for the Home Department v AF (No. 3) [2009] UKHL 28 (“AF-disclosure”) does not apply in a challenge to the seizure, download, retention and inspection of the contents of a person’s mobile phone by an examining officer pursuant to Schedule 7 of the Terrorism Act 2000 (“TA 2000“).
In addition to undertaking a comprehensive review of the AF-disclosure case law, Chamberlain J also rejected the notion of some form of an intermediate level of disclosure in closed material proceedings, where the AF-disclosure threshold is not met. The decision offers some much-needed clarity in this area of law.
BACKGROUND FACTS
The Claimant, Mr Ansari, is an experienced solicitor specialising in national security and human rights work. In 2024, he was instructed by the Palestinian Islamic Resistance Movement (commonly known as Hamas) to apply to the Home Secretary for the de-proscription of that group under the TA 2000.
On 6 August 2025, whilst returning from a family holiday in Ireland, the Claimant was stopped, questioned and detained by officers of the North Wales Police. His mobile phone was seized, and its contents were downloaded and copied before being returned to him. The Chief Constable then instructed leading counsel to undertake a ‘sift’ of those contents (i.e., to apply various search terms give to them by police, and to then determine whether anything flagged against those terms contained privileged information, which would be destroyed).
The Claimant issued judicial review proceedings against the Chief Constable and the Home Secretary, challenging the former’s decision to question and detain him, and also to copy and retain the contents of his phone. On 24 October 2025, Chamberlain J refused Mr Ansari’s application for an interim injunction to prevent the ‘sift’ from occurring until his claim had been tried and determined, and made a section 6 Justice and Security Act 2013 declaration (a prerequisite for a closed material application to be made to the court): R(Ansari) v Chief Constable of North Wales Police [2025] EWHC 3330 (Admin).
A Special Advocate was subsequently instructed to represent Mr Ansari’s interests in the closed proceedings, leading to the decision with which this case comment is concerned.
It was assumed by the Defendants that the Claimant’s Article 6 ECHR rights were engaged. That being so, there remained one outstanding point of contention: was the Claimant also entitled to AF-disclosure? If answered in the affirmative, the Claimant would have been entitled to a ‘gist’ of the sensitive/confidential allegations made against him, even if such disclosure would have been damaging to national security.
The Claimant contended the answer to that question was in the affirmative for several reasons. The claim had been brought to vindicate his Art. 8 ECHR right to respect for private and family life, with his phone’s contents spanning some 15 years of his life: [46].[1] Moreover, the phone largely contained confidential privileged information, which was also protected by Art. 8: [47]. With disclosure, the Claimant could potentially provide a proper explanation of any matters said to justify the search/seizure; further, such disclosure was needed to adequately protect his clients’ privileged information: [48]. In addition, the interference with the Claimant’s rights had not only occurred in the past (i.e., the events on 6 August) but was ongoing (the continuing examination of his data) and prospective (any future use of his data): [49]. Finally, if AF-disclosure applied, the fact that the Claimant had some knowledge of the allegations against him was insufficient; and in any event, what had been disclosed so far was plainly inadequate: [50].
The Chief Constable contended that AF-disclosure did not apply here, chiefly because the decisions complained of fell far short of the coercive threshold (amounting to a deprivation of one’s liberty or similar) which arose in the AF case law: [52]. AF-disclosure had not been applied to analogous challenges to the retention of material obtained pursuant to search warrants (Haralambous [2018] UKSC 1): [53]. The Supreme Court’s analysis of the Sch. 7 powers in Beghal [2015] UKSC 49 indicated that such powers were a minimal (and justified) interference with fundamental rights: [54]. Finally, AF-disclosure applied in cases where it was the State which was making a case against an individual, who then had to rebut or disprove it. Here, however, the issue was not whether the CLOSED allegations against the Claimant were true, but rather whether there had been a lawful basis for conducting the search. The Special Advocate could make submissions without requiring disclosure of the allegations to the Claimant: [55].
THE DECISION
Chamberlain J agreed with the Chief Constable that AF-disclosure did not apply here. The claim fell within a similar category as Haralambous qua search warrants: [75]. The exercise of Sch. 7 powers did not involve any allegation against Mr Ansari specifically; nor did the seizure of his personal data affect his substantive legal position (i.e., it did not impose obligations upon him); and if the data was subsequently used to bring criminal proceedings against him, he would be entitled to the full panoply of procedural protections: [76]. That the Claimant’s phone contained privileged information was not a distinguishing factor, given (i) there were protective safeguards in place; and (ii) any criminal proceedings brought against the Claimant’s clients arising out of the use of that information would also be subject to the same procedural protections that he would be entitled to: [77].
The more interesting section of the judgment, however, concerns the judge’s views on the AF case law. Earlier decisions had rationalised AF-disclosure as falling somewhere on a spectrum of cases where, at one extreme (detention; asset-freezing) such disclosure was necessary; and at the other end, the minimal interference with an individual’s rights or freedoms (employment vetting) did not so require.
However, a strand of cases (e.g., K, A and B [2017] EWHC 830 (Admin)) had also suggested the possibility of an ‘intermediate’ form of disclosure – i.e., something less than AF-disclosure, but also more than simply nothing. Chamberlain J referred to this as a “spectrum of disclosure standards”: [57]. For both principled and practical reasons, Chamberlain J powerfully rejected the existence of this latter spectrum: see [58]-[65].
AF-disclosure is itself the “core irreducible minimum” needed for an individual to properly give instructions to a Special Advocate. It would be entirely pointless to disclose less than the bare minimum (whilst also undermining national security interests):
“60. …If the court were to apply some lesser disclosure standard, then, by definition, the excluded person would not be given sufficient to enable him to mount an effective challenge to the case against him. He would be given less than the core irreducible minimum, but would nonetheless be entitled to some disclosure which would damage the interests of national security.
61. …Why should the court countenance damage to national security so as to provide a hearing which does not offer the excluded party the minimum disclosure necessary to mount an effective challenge to the case against him?”
Chamberlain J further cited the inherent institutional limitations of a court in determining precisely how much damage to national security is ‘acceptable’, and in what types of cases this should occur in: [62]. The task for the court is simply to consider whether the case is one which requires AF-disclosure; and if so, to determine what the ‘gist’ provided to the individual must include: [63].
The judge further considered that:
- Insofar as AF-disclosure is concerned, no principled distinction can be drawn between backward-looking claims (where the harm has already crystallised), and forward-looking claims (where the restriction on liberty is prospective or ongoing): [66]-[69].
- The fact that the present case concerned a challenge to the rationality of the impugned decisions, as opposed to the correctness of the material upon which the decisions were taken, also cannot (on its own) amount to a distinguishing factor: [70]-[72].
- Whether AF-disclosure should be ordered falls to be determined by reference to (primarily) the nature of the right in issue in the proceedings; although policy considerations may play a secondary role: [73]-[74].
COMMENTARY
Ansari is a much-needed clarification of the law in this area by a judge who has extensive experience with closed material proceedings, both as a Special Advocate at the Bar and now on the bench.
The reassertion of the ‘bright line’ approach to AF-disclosure offers some certainty as to the standard of disclosure required. The thornier question remains whether, on the facts of a particular case, the AF threshold is met. Other commentators have previously criticised the courts’ inconsistent approach to the threshold question.[2]
Critics of closed material proceedings, however, will no doubt be less sanguine about the ability of Special Advocates to properly represent an excluded party’s interests. Some of those limitations are inherently structural, such as the inability to communicate with the excluded party once in CLOSED.
More significantly, however, there have been concerns over proper resourcing and prioritisation of reform. Long time followers of this blog will recall the warning flare sent up by 1COR’s own Angus McCullough KC in late 2023. Only time will tell whether the limited recommendations accepted by the government in its 2024 response to Sir Duncan Ouseley’s 2022 report into the operation of closed material procedures will lead to further improvements to the system.
Kian Leong Tan is a future pupil barrister at 5 Essex Chambers. A member of 5 Essex Chambers is instructed on behalf of the Chief Constable of North Wales Police in the Ansari litigation, but was not involved in the writing of this article.
[1] In R (Liberty) v SSHD [2019] EWHC 2057 (Admin), the High Court recognised that a mobile phone contains “the sum of an individual’s private life”.
[2] Hayley J. Hooper, ‘A Core Irreducible Minimum? The Operation of the AF (No. 3) Duty in the Closed Material Procedure’ in A Higgins (ed.), The Civil Procedure Rules at 20 (OUP, 2020).
