High Court Rules Amendment to Modern Slavery Guidance Unlawful in Landmark Judgment (10 July 2026)

The High Court has handed down its judgment in the litigation related to the Treaty between the UK and France on the Prevention of Dangerous Journeys, or the ‘One In, One Out’ deal, which came into force on 6 August 2025.

The key question for the High Court to determine in this judgment was whether it was lawful for the Secretary of State for the Home Department to amend statutory guidance published under the Modern Slavery Act 2015 to remove the right to request reconsideration of negative human trafficking decisions for individuals being removed to a country which is a signatory to ECAT and the ECHR, such as France. In his judgment, Mr Justice Sheldon found that this amendment was unlawful.

BACKGROUND

In the evening of 17 September 2025 and following the High Court’s granting of an injunction restraining a victim of trafficking’s removal to France under the Treaty in R(CTK) v Secretary of State for the Home Department [2025] 2622 (Admin) (16 September 2025) (a case in which the claimant was also represented by Duncan Lewis and Counsel from Garden Court Chambers), the Secretary of State for the Home Department (“SSHD”) decided to remove the right of a putative victim to request reconsideration of a negative trafficking decision in circumstances where she intends to remove that person to a third country which is a signatory to the European Convention on Human Rights (“ECHR”) and the Council of Europe’s Convention on Action Against Trafficking (“ECAT”). Disclosure in the proceedings revealed that the central reason for the amendment was to “ensure that reconsideration is not a barrier to effective implementation of the Treaty.”  

IMPORTANCE OF EFFECTIVE MECHANISMS FOR IDENTIFYING VICTIMS OF TRAFFICKING

The SSHD has various duties under international and domestic law relating to the identification of victims of trafficking present in the UK. The paramount importance of effective procedures to identify such victims was not in dispute between the parties, not least because this identification acts as a gateway to further fundamental rights and support for vulnerable individuals.

Since 2013, the UK’s framework for doing so has included the right of putative victims to request reconsideration of a negative decision where, for example, new evidence has come to light which casts doubt on the correctness of that decision. Alternatively, a request for reconsideration could be made where there are specific concerns that a decision was not made in line with the Modern Slavery Statutory Guidance, published pursuant to section 49 of the Modern Slavery Act 2015 – the guidance which is intended to comprehensively outline the SSHD’s framework generally for meeting her legal obligations in terms of trafficking and modern slavery.

In recent years, as the rate of positive decisions has drastically dropped since 2023, the right to request reconsideration has become of increasing importance with more requests being submitted and, as raised in this case, in 2025 79% of reconsidered decisions lead to a positive outcome.

THE CLAIM

Duncan Lewis represents two of the lead claimants in this litigation - one of whom, KAG, was removed following a negative initial trafficking decision (Reasonable Grounds). He is an Eritrean asylum-seeker who arrived in the UK by small boat in August 2025 and was immediately detained. Shortly thereafter he was told by the SSHD that she intended to remove him to France under the UK-France agreement.

He instructed Duncan Lewis and was subsequently referred to the National Referral Mechanism (the UK’s framework for identifying and supporting victims of trafficking) in September 2025 but swiftly received a negative decision which said that there were not reasonable grounds to believe that he was a victim.

In October, Duncan Lewis submitted further evidence in support of KAG’s trafficking claim, including a detailed witness statement, an expert trafficking report and a medico-legal report, with a request that the negative decision be reconsidered. The SSHD refused to do so, relying on the amendment of 17 September 2025 to say that KAG had no right to such reconsideration. KAG was then removed to France whereupon he filed his Judicial Review.

He challenged the amendment to the policy on the following grounds:

1. The amendment was unlawful as it constituted a fetter of the SSHD’s discretion;
2. The decision to make the amendment was taken in breach of the Tameside principle in that the SSHD had failed to make sufficient inquiry as to the relevant factors;
3. The amendment was made contrary to the Padfield principle in that it frustrated the purpose of the statute;
4. The amendment was unlawful as it induced decision-makers into unlawful conduct.

By his further grounds, KAG challenged the lawfulness of the individual decisions made by the SSHD in his case including his selection for inclusion in the UK-France scheme. These grounds will be heard at a separate closed hearing later this year. 

Another lead claimant represented by Duncan Lewis, AYA, was granted interim relief by the High Court in March restraining his removal until after the Court’s final judgment. He was subsequently notified by the SSHD that she no longer intended to remove him to France pursuant to the Treaty but continues to pursue the claim.

THE JUDGMENT

Sheldon J agreed with the claimants that the decision to remove the right to reconsideration was unlawful as it created a system of identifying victims of trafficking which was less robust and effective. The consequence of the amendment, he found, is that in many cases, it will lead to identification decisions that are not accurate and so could not have been within the contemplation of Parliament [124-125].

Mr Justice Sheldon also held that it brought about an unlawful fettering of the SSHD’s discretion as it means that she is depriving herself of considering evidence that could be decisive of an individual’s claim to be a trafficking victim. For similar reasons, he concluded that the amended policy breached the Padfield principle, stating that: ‘the amendment to the reconsideration policy undermines the effectiveness of the mechanism for identification in a significant way’ and ‘this cannot be said to further the purpose and objects of the [Modern Slavery Act 2015] and, in fact, frustrates them’ [164]. As a result of the above, the policy and its implications for victims are unlawful as it will induce decision-makers to act unlawfully in failing to reconsider cases which ought to be reconsidered, thus breaching the principles identified by the Supreme Court in the case of R(A) [166].

One of the lead solicitors in the claim, Elizabeth Cole, said:

”We welcome the Court’s determination that the SSHD’s decision to amend the modern slavery guidance to remove the right to reconsideration for those she intends to remove to an ECAT/ECHR signatory was unlawful. This has had significant consequences: large numbers of vulnerable people have been unlawfully removed to France as a result. We now urge the SSHD to acknowledge her obligations under both the treaty and domestic law, and bring our client, as well as potentially many others who have been unlawfully removed, back to the UK”

A lead claimant represented by Duncan Lewis has said:

“It is really a feeling of hopelessness that I have. I believe that the Home Office had all the evidence in my case, but chose not to consider this. In their doing so, they failed to consider my case properly. I truly believe if they had properly considered my evidence, I would not have been returned to France.

“When a lot of individuals enter the United Kingdom to seek refuge, and have experienced a lot of difficult situations, being further mistreated is simply heart-breaking. The overwhelming sentiment is that they do not treat people equally. Some people they place in hotels, some they return to France, like me. Ultimately, it left me with a large question mark as to why I had to be treated differently”.

 The litigation concerning the operation of the UK-France agreement continues.

The legal team at Duncan Lewis is led by Toufique Hossain, Elizabeth Cole and Jodie Spencer and includes Thomas Munns, Marina Khan, Simon Robinson, Katie Nelson, Nadia Roberts and Maria Thomas.

Counsel instructed were Sonali Naik KC, Gordon Lee, Josephine Fathers, Ronan Toal of Garden Court Chambers, Eleanor Mitchell, James Robottom and Jessica Sutton of Matrix Chambers and Catherine Meredith of Doughty Street Chambers. 

Duncan Lewis is grateful for the support of various individuals and organisations for their support in the litigation. These include Forum Refugies, Utopia 56, Care for Calais, Anti-Slavery International, and Unseen UK.

Our Public Law Team

Duncan Lewis’ Public Law team, ranked in Chambers & Partners and The Legal 500 UK directories, has a broad practice representing both privately and publicly funded (legal aid) clients in matters involving immigration; asylum and human rights and deportation matters, with a niche practice in immigration and civil liberties claimant judicial review matters. They have significant practice in challenging delays in Home Office decision-making, unlawful immigration detention cases with high net claims for damages and challenging immigration removal decisions, particularly third country removal cases