EXR, R (on the application of) Secretary of State for the Home Department (No 3)

A decision treating an unaccompanied asylum-seeking child as an adult for removal purposes is subject to conventional reasonableness review with anxious scrutiny. Where the Home Secretary relies on a local authority age assessment, she must independently satisfy herself that it is Merton-compliant, including that material documents have been considered and relevant doubt has been resolved in the claimant’s favour. A restricted reassessment may not cure an earlier defect if it excludes relevant evidence or denies the claimant a fair opportunity to participate. The judicial review duty of candour is continuing and requires disclosure of records and correspondence materially relevant to the challenge. Anxious scrutiny may show that an error is immaterial or that the same outcome was highly likely, but that conclusion must be supported by the evidence.

EXR arrived in the United Kingdom in September 2025 and initially gave his date of birth as 22 July 2000. He later said he was born in 2008 and produced a scanned birth certificate. The Secretary of State for the Home Department treated him as an adult, made an inadmissibility decision and scheduled his removal to France under the UK-France Treaty 2025. Hillingdon Council’s age assessments also concluded that he was an adult. The High Court had addressed the applicable review standard and related questions in two earlier judgments in the same claim: [2026] EWHC 1568 (Admin) and [2026] EWHC 1726 (Admin).

This third judgment considered the reasonableness of the successive age decisions, whether the Secretary of State could rely on Hillingdon’s assessments, and compliance with the duty of candour in relation to three proposed removals.

1. The claim for judicial review was allowed in respect of the decisions to treat EXR as an adult, the resulting inadmissibility decisions and the proposed removals. The first two age decisions, made on 30 September and 13 October 2025, were reasonable. The reasonableness of the third decision, made on 23 October 2025, remained unresolved and had been superseded.
2. The later decisions were unreasonable. The Secretary of State had no documented reasoned basis for relying on Hillingdon’s November 2025 assessment, which had failed to address the scanned birth certificate. In January 2026, Hillingdon was asked to conduct a restricted reassessment without being told that the Home Office had recorded the earlier assessment as not shown to be Merton-compliant. The claimant was not told about the reassessment or given an opportunity to participate. The reassessment addressed the birth certificate but omitted the claimant’s relevant witness statement. The court relied on R (M) v Waltham Forest LBC [2021] EWHC 2241 (Admin) for the proposition that a reassessment should recognise flaws in the earlier assessment.
3. The Secretary of State could not reasonably rely on the two assessments, individually or together, as Merton-compliant. That made the decisions of 28 November 2025, 2 February 2026 and 9 March 2026 unreasonable. The 18 March 2026 refusal to review the age assessment could not stand because it rested on the mistaken premise that the prior age decision was reasonable.
4. The Secretary of State seriously breached the continuing duty of candour. The Home Office did not consult the primary ATLAS record, which recorded the absence of sufficient evidence of Merton compliance, and later failed to disclose correspondence with Hillingdon about the restricted reassessment. The claimant’s ability to make related arguments did not cure the non-disclosure. The court also considered the possibility of a permission-stage assurance concerning candour, referring to R (Police Superintendents’ Association) v Police Remuneration Review Body [2023] EWHC 1838 (Admin).
5. Anxious scrutiny can assist a public authority where it shows that decision-making was reasonable, an error was immaterial, or the same outcome was highly likely. The court considered R (YH) v SSHD [2010] EWCA Civ 116 and R (MN) v SSHD [2020] EWCA Civ 1746. On the evidence here, the court found no basis to conclude that EXR’s case was manifestly contrived or that the errors were immaterial. It left remedy for later consideration.
6. The court quashed the four specified age decisions and declared the inadmissibility and removal decisions unlawful. It declared serious breaches of the duty of candour. The Secretary of State was ordered to pay the claimant’s costs, with a 35% payment on account, and to file a witness statement addressing the candour breaches by 16 November 2026.

This was a first-instance judicial review judgment. It records two earlier judgments in the same claim, [2026] EWHC 1568 (Admin) and [2026] EWHC 1726 (Admin) , which addressed the review standard and related issues. No appeal was determined in this judgment.