The Home Office faces a legal challenge over a policy that stripped almost 1,500 EU citizens of some or all of their rights to live in the UK. Campaign group the3million filed papers at the high court on Friday, alleging that the department breached protections contained in the Brexit withdrawal agreement.

The challenge follows cases involving EU citizens who received pre-settled status after Brexit but were subsequently informed that it had been awarded by mistake. The group argues that the Home Office removed rights without providing an appeal or considering whether its decisions were proportionate, including the consequences for people who had established their lives in Britain in reliance on the original grants.

One affected person is a 33-year-old Brazilian Italian engineer who has lived in London since 2018. He was initially told he should not have settled status and that, although he could remain, his Brazilian wife could not. That decision was reversed in recent weeks following objections. Another person who contacted the3million works for the NHS and is pursuing a dentistry PhD. She said the notification had “turned her life upside down”.

Several cases concern Brazilians with Italian parents or grandparents whose citizenship derives from ancestry through jure sanguinis. The Home Office had told some that their status was granted incorrectly because they declared Italian citizenship without presenting an Italian passport when applying. Those affected complained that pandemic closures of public institutions had prevented them from obtaining passports.

In October 2026, the department accepted that someone who supplies evidence of Italian citizenship obtained through jure sanguinis would be recognised as Italian from birth. Monique Hawkins, acting chief executive of the3million, said that reversal demonstrated that the Home Office could revise its approach when errors were exposed. She argued that the department was denying people a fair assessment and an appeal on the basis of its own conclusion that the withdrawal agreement did not cover them.

The campaign group wants the court to declare the policy unlawful under the withdrawal agreement, common law or both, and order the removal of the relevant provisions from the published policy. Its court papers say efforts to secure a change through advocacy have continued since early 2025 without persuading the department to alter course.

Lawyers also argue that the design of the EU settlement scheme makes the policy more problematic. The UK adopted requirements that were more generous in some respects than the withdrawal agreement demanded. Hawkins said flexible evidence rules and discretionary decisions left many recipients unable to establish whether their status rested on the agreement, domestic immigration rules, caseworker discretion or an actual mistake.

The proceedings follow an earlier successful challenge to the Home Office’s implementation of the agreement. In 2022, the Independent Monitoring Authority, supported by the3million, contested requirements for people to reapply for settled status when their pre-settled status expired. The watchdog argued that those conditions threatened EU citizens’ rights to work or rent housing, and high court judges found the requirements unlawful.

A Home Office spokesperson declined to comment on the latest challenge because the legal proceedings are continuing.