Background
This is a sequel judgment addressing the standard of review governing decisions about whether an unaccompanied individual should be treated as an adult or child in two distinct contexts. The case arises from challenges to removal proposals under the UK-France Treaty 2025 (UFT). In a prior judgment ([2026] EWHC 1568 (Admin)), the court determined that a reasonableness standard applies to decisions treating unaccompanied individuals as adults for UFT removal purposes. This judgment clarifies four key aspects of that reasonableness standard and addresses a separate question about the standard applicable to age determinations in human trafficking victim assessments.
The claimant is an unaccompanied individual who arrived in the UK on a small boat from France. The Secretary of State for the Home Department (SSHD) proposed their removal to France under the UFT arrangements. Because unaccompanied children are ineligible for removal under the UFT, the SSHD’s decision to treat the claimant as an adult is legally dispositive. The claimant contests this age assessment and brings judicial review proceedings.
Separate from the UFT context, the judgment also addresses age determinations made within the National Referral Mechanism for assessing whether individuals are victims of human trafficking. When an unaccompanied individual is referred as a potential trafficking victim and a Reasonable Grounds (RG) decision is made treating them as an adult, the standard of review for that age determination presents a distinct legal question.
The Court’s Holding
On the Reasonableness Standard for UFT Removals (Four Key Aspects): (1) Closeness of scrutiny: The doctrine of “anxious scrutiny” applies when reviewing SSHD decisions to treat unaccompanied individuals as adults for UFT removal. The public interest in the effective working of the UFT arrangements does not reduce the intensity of judicial review. The court rejected the submission that institutional or constitutional considerations should lower the standard of scrutiny. The exclusion of unaccompanied children from the UFT is deliberate and grounded in child protection rationale, making heightened scrutiny appropriate. (2) Fresh evidence: Claimants may point to fresh evidence post-dating the SSHD’s decision to treat them as an adult. If new material was not previously considered, it can be presented as a Lumba adherence argument—contending that the SSHD is unlawfully refusing to consider the new evidence. Such evidence is admissible in judicial review proceedings. (3) Merton-compliance collateral challenge: Where the SSHD relies on a local authority age assessment as “Merton-compliant,” a claimant may collaterally challenge whether the assessment meets the legal standards required for Merton-compliance. Merton-compliance is an objective legal standard identifying minimum procedural fairness requirements. Courts are institutionally well-placed to assess it directly. However, reasonableness remains the overarching legal test. In practice, there is limited space between finding Merton non-compliance and finding it unreasonable for the SSHD to have concluded otherwise. (4) Scope of the reasonableness test: The reasonableness standard may apply to either a decision that the individual is “significantly over 18” (as in the “significantly over 18 policy”) or simply “over 18,” depending on the facts and reasoned decision-making in the individual case. Given the exclusion’s nature and child protection rationale, benefit-of-the-doubt considerations may be legally significant.
On Age in Human Trafficking Victim Determinations: The correctness standard of review applies where age is a factor in determining whether an individual is a victim of human trafficking. The court held that the Slavery and Human Trafficking (Definition of Victim) Regulations 2022 (reg. 3) contain “adult-only elements” (AOE)—requiring specific methods of trafficking only for adults—and “child-only elements” (COE)—addressing sexual exploitation offences against children. Where age engages these AOE or COE in the victim test, the decision-maker’s classification of the individual as an adult or child attracts the correctness standard, not reasonableness. This reflects the objective legal standard created by the statutory definition of victim under the Modern Slavery Act 2015, the 2022 Regulations, and the European Convention on Action against Trafficking in Human Beings (ECAT). The statute and regulations create a framework distinguishing adult and child victims, and courts apply the correctness standard to verify whether age-based elements were correctly applied.
Key Takeaways
- Age assessments for UFT removal decisions are subject to “anxious scrutiny” under the reasonableness standard; the public interest in treaty implementation does not diminish this standard.
- Merton-compliance—the procedural fairness standard for local authority age assessments—is an objective legal standard that courts can assess directly, even while applying a reasonableness test to the SSHD’s reliance on such assessments.
- Fresh evidence post-dating an age decision is admissible in judicial review and can support a Lumba adherence argument that the SSHD unlawfully refused to reconsider.
- Age determinations in human trafficking victim assessments are subject to the correctness standard where they engage statutory adult-only or child-only elements of the victim test, not the reasonableness standard.
- The victim test under the Slavery and Human Trafficking Regulations distinguishes adult and child victims because the methods required to establish trafficking differ by age; this statutory distinction creates an objective legal framework for age review.
Why It Matters
This judgment resolves critical uncertainties about how courts review age assessments in two overlapping but legally distinct regimes: immigration removal decisions and modern slavery/trafficking determinations. For immigration practitioners, the holding on anxious scrutiny and Merton-compliance collateral challenges provides important procedural tools. The court confirmed that the public interest in effective treaty implementation cannot be invoked to weaken child-protection scrutiny—a principle with broader implications for immigration law. For trafficking and modern slavery advocates, the application of the correctness standard to age determinations in the victim test is significant because it places age assessment on firmer legal footing, rather than subjecting it to the more deferential reasonableness review.
The judgment reflects Parliament’s and the European Convention’s emphasis on child protection in the trafficking context. By importing the ECAT’s victim test into domestic law, Parliament created objective legal standards about age that courts must enforce with precision. The court’s willingness to apply the correctness standard in this context acknowledges that modern slavery determinations rest on statutory definitions that admit of correct and incorrect applications, distinguishing them from discretionary policy decisions. This holding extends beyond UFT removals and trafficking to all contexts in which the Modern Slavery Act victim test is applied, including non-immigration settings.