On 6 July 2023, the Divisional Court (the "Court") handed down its judgment in high profile judicial review proceedings brought by the Cabinet Office against the Chair of the UK Covid-19 Inquiry (the "Chair" and the "Inquiry"), ruling in favour of the Chair. The judgment, R (Cabinet Office) v Chair of the UK Covid-19 Inquiry [2023] EWHC 1702 (Admin), held that the Chair was entitled to require the Cabinet Office to produce notes made by former Prime Minister Boris Johnson, as well as certain WhatsApp messages on the devices of Mr Johnson and Mr Henry Cook, a former senior adviser to Mr Johnson.

This blog post provides an overview of some of the key aspects of the Court's judgment, which the Cabinet Office has stated it will not appeal. The judgment confirms that a statutory inquiry may lawfully issue a notice under section 21 of the Inquiries Act ("IA") to require the production of a class of documents encompassing both relevant and irrelevant documents.


A more detailed explanation of the background to the case and the arguments raised by the Cabinet Office and the Chair are available in our previous blog post. In short, the Cabinet Office's challenge concerned a section 21 IA notice issued by the Inquiry, requiring the Cabinet Office to produce, in largely unredacted form, diaries and copies of 24 notebooks containing Mr Johnson's notes, as well as certain WhatsApp messages on the devices of both Mr Johnson and Mr Cook, covering the period of 1 January 2020 – 24 February 2022 (the "Notice").

The chief point in dispute was whether in issuing the Notice, the Chair acted within her power under section 21(2)(b) IA, which states that the Chair may compel a person "to provide any documents in his custody or under his control that relate to a matter in question at the inquiry" (emphasis added).

The Cabinet Office argued that section 21(2)(b) IA only covered objectively relevant documents, while the Chair contended she was permitted to compel production of "documents that the Chair reasonably considers are potentially relevant to her ongoing investigation" (emphasis added). Mr Johnson and Mr Cook participated in the proceedings as interested parties, with counsel for the former making submissions in support of the Chair's position, and counsel for the latter explaining Mr Cook's involvement in the circumstances underlying the case but remaining neutral. The Chair of the Scottish Covid-19 Inquiry made a written intervention in support of the Chair.

The Court's judgment

The Cabinet Office was granted permission to apply for judicial review following a "rolled-up" hearing, where the permission and substantive merits stages of the proceedings were combined into one. However, the Court (Dingemans LJ and Garnham J) ruled in favour of the Chair on the substantive issues, holding that the Notice had been validly issued, and that there was no irrationality in the Chair's approach.

Notice validly issued

The Court's starting point was that the Notice did require the production of documents that "relate to a matter in question at the inquiry", in line with the wording in section 21(2)(b) IA. The WhatsApp messages sought were either from a group chat created to communicate about the Government's Covid-19 response or were exchanged between specific individuals working on the response. Similarly, the Court stated that Mr Johnson's notes were "very likely to contain information about decision making relating to the Covid-19 pandemic".

The Court went on to address the Cabinet Office's objections regarding how the Notice's broad scope meant that it would inevitably require the production of irrelevant documents. The Court was clear that, contrary to the Cabinet Office's position, "the fact that the section 21 notice will yield some irrelevant documents does not invalidate the notice or mean that the section 21(2)(b) [power] cannot be lawfully exercised". The Court reached this conclusion for three principal reasons: (i) the inquisitorial nature of statutory inquiries, (ii) the treatment of irrelevant documents in civil disclosure, and (iii) the IA's existing framework for dealing with irrelevant documents.

i. The inquisitorial nature of statutory inquiries

The Court drew a distinction between statutory inquiries and "parties in civil proceedings". In the Court's view, previous case law highlighted that statutory inquiries are afforded "latitude" to "enable them to "fish" for documents". This permits statutory inquiries to "make informed but speculative requests" in pursuit of existing lines of inquiry, or to develop new lines of inquiry. The Court accepted that notices issued by a statutory inquiry for such purposes would be "bound to lead to the inclusion of some irrelevant material".

ii. The treatment of irrelevant documents in civil disclosure

The Cabinet Office had contended that the Notice went far beyond well-established approaches to disclosure in civil proceedings, given the Notice was unqualified by subject matter or content. The Court was unpersuaded by this argument, noting that it had been "common ground that the analogy with civil proceedings could only be a loose one". The Court also pointed out that it was "well known" that ordinary disclosure requests in civil proceedings can validly lead to the disclosure of irrelevant documents, including under a provision of the former Rules of the Supreme Court similarly worded to section 21(2)(b) IA. The Court reasoned that it would therefore be "surprising" if a section 21 IA notice was rendered invalid for similarly catching irrelevant documents.

iii. The IA's existing framework for dealing with irrelevant documents

Finally, the Court explained that the IA's framework envisages, and sets out an approach for dealing with, circumstances where a section 21 IA notice captures irrelevant documents as part of a broader set of lawfully requested documents. Section 21(4)(b) IA allows a person who wished to withhold a document on the basis of irrelevance to make an application to the Chair on the grounds that it would not be "reasonable in all the circumstances to require him to comply with such a notice".

In such a case, "it will be for the Chair of the Inquiry to determine how to deal with such a contention". Should an inquiry chair decide that the document in question does not in fact relate to a matter in question at the inquiry, the inquiry chair "will not be entitled to retain the document". Should the inquiry chair decide that the document does relate to an inquiry matter, a person still wishing to resist production would be able to "invite" the inquiry chair to certify the matter for High Court determination under section 36 IA. In its concluding remarks, the Court expressly recorded that going forward, the Cabinet Office could choose to avail itself of this process in relation to the Notice.

No irrationality

In light of its reasoning on the validity of the Notice, the Court regarded the Cabinet Office's contention that the Chair had acted irrationally as unsustainable. The Cabinet Office's case on irrationality relied on its interpretation of section 21(2)(b) IA, which had been rejected by the Court. There was nothing irrational in the Chair issuing a notice which caught both "obviously relevant" and "obviously irrelevant" documents.


As we said in our previous blog post, the significance of the Court's judgment extends well beyond the specific context of the Covid-19 Inquiry itself. The judgment confirms a statutory inquiry's prerogative to "fish" for documents by making "informed but speculative requests for documents relevant to lines of inquiry, or documents which lead to new lines of inquiry". The judgment also provides useful guidance on how core participants might deal with concerns regarding the production of irrelevant material within the framework of the IA. Judicial reviews of statutory inquiries are few and far between but this one will certainly be a reference point for years to come.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.