Public Law Update, Part 1: Appeals to Rationality…

In a recent Landmark Chambers webinar, Miranda Butler and Charles Bishop reviewed significant developments in public law procedure and practice in the previous months. This blog builds on the content of that webinar with the aim of providing practitioners with an update on recent case law and its implications.

Introduction

Two recent, high-profile public law cases have considered rationality in decision-making and the approach to be taken by courts considering rationality challenges.

The Spitalfields Historic Building Trust decision

The first is R (The Spitalfields Historic Building Trust) v London Borough of Tower Hamlets [2025] UKSC 11. This case concerned a decision on a planning application decision made by the London Borough of Tower Hamlets (“the Council”) development committee.

Old Truman Brewery Ltd., the second respondent, applied for planning permission to redevelop an old brewery in Spitalfields. The application came before the Council’s development committee at a meeting on 27 April 2021. Five members of the committee were present. The committee voted unanimously to defer consideration of the proposal. The committee next considered the planning application at its meeting on 14 September 2021. However, in the intervening period, the Council’s standing orders had been amended to provide that members who had not been present at an earlier meeting were unable to vote on a matter that had been the subject of a vote at a first meeting. As a result, only three councillors were able to vote in the September meeting, and the planning application was allowed by two votes to one.

The Spitalfields Historic Building Trust challenged the decision to grant permission, arguing that the powers and statutory principles under which local authorities make their standing orders could not be read so as to preclude councillors, who were elected by members of the public, from voting, and thereby indirectly disenfranchising the public.

The Supreme Court rejected this argument. Lord Sales (with whom the other justices agreed) considered that the appellant’s argument required them to read down the straightforward language of the relevant legislation with the effect that they would prevent any infringement on the right to vote.

The appellant also argued, in the alternative, that the court should consider this to be a matter concerning fundamental rights, namely, the right to vote, which could not be curtailed absent express statutory authorisation. This too was rejected. The right of a councillor to vote was not one that could be regarded as absolute or fundamental. As such, the power to make standing orders was subject to ordinary public law principles rather than the “anxious scrutiny” test:

“69. One way in which general and clear wording of a statutory provision might be read down is by reference to the principle of legality, that where there is an established or fundamental right recognised in law then Parliament, by its use of general language in the particular context, is taken to have legislated in a way which is not intended to abrogate that right: see, eg, R v Secretary of State for the Home Department, ex p Simms [2000] 2 AC 115, 131 (Lord Hoffmann). …

70. However, no such principle of interpretation is engaged in the present context. The right of councillors to vote on business of the local authority is not an established right recognised by the common law outside the statutory regime of which it forms part.”

The Supreme Court’s approach in the case is to be contrasted with its own approach in Osborn v Parole Board [2013] UKSC 61. In that case, which concerned fairness in parole board hearings, a more dynamic approach was taken to the concept of fundamental rights, with acceptance that common law rights may interact with rights created under statute. In Spitalfields, however, the Court was clear that, although the right of a councillor to vote was underpinned by and essential to a statutory framework, it was not an established right capable of engaging the principle of legality of requiring anxious scrutiny.

R (on the application of KP) v Foreign, Commonwealth and Development Affairs

The second decision was the High Court’s recent judgment in R (KP) v Secretary of State for Foreign, Commonwealth and Development Affairs & Anor [2025] EWHC 370 (Admin). KP concerned an individual with a significant criminal record who had been refused entry into the UK, despite the fact that he was being detained in Diego Garcia in very concerning circumstances. It was agreed that the claimant could not be sent to Sri Lanka and there was no third country currently willing or able to take him. The Home Secretary nonetheless declined to grant him leave to enter.

The decision was challenged, inter alia, on the basis of rationality. The question for the High Court was whether the Secretary of the State had acted unreasonably in refusing KP leave, considering the risk to his health and life on Diego Garcia, and considering that there was no realistic prospect of a third country accepting him in the foreseeable future.

Chamberlain J held that the Secretary of State’s decision was lawful. The case provided a helpful exposition of the principles of rationality, including their flexible nature:

The Court’s approach to assessing the rationality of a decision varies depending on the importance of the interests affected by it. This does not necessarily involve a requirement to identify a ‘right’, but rather, to focus on the gravity of the consequences [76].
Where anxious scrutiny applies, it will require the court to undertake a rigorous examination of the defendant’s process and to show that every factor which might tell in favour of an applicant has been properly taken into account (process rationality). In complaints of outcome irrationality, more will be required by way of justification, and the importance of the interests affected may potentially narrow the range of decisions open to the decision-maker, potentially to just one [77].
When considering outcome irrationality, the Court does not only look at the claimant’s interests but also the importance of the public interests on the other side of the balance. Institutional deference may apply here, requiring particular weight to be given to a democratically elected decision-maker's view and/or expertise.

On the facts of KP’s case, a rational assessment had been made that there was a realistic prospect of a third country accepting the claimant. In particular, the Secretary of State had been entitled to rely on the particular expertise provided by the Foreign, Commonwealth and Development Office. While there were risks to the claimant on Diego Garcia, these had rationally been balanced against the risks to the public and to public confidence if he were permitted to enter the UK. As such, the decision was one that it was reasonable for the SSHD to take.

This article is written by Miranda Butler.

You can watch the full webinar recording here.