On June 15, 2026, five judges at Britain's Court of Appeal overturned a February court decision and ruled that the Home Secretary was legally justified in banning Palestine Action as a terrorist organisation under the Terrorism Act 2000.

The reversal closed an unusual chapter in which the government had banned a group using counter-terrorism laws, only to have a senior court declare the ban unlawful and excessive. In February, the High Court had found that only a small portion of Palestine Action's conduct actually met the legal definition of terrorism. Most of what the group did — damaging property, trespassing, painting buildings that belong to defence contractors — was ordinary crime that could be handled through standard criminal law without needing to invoke anti-terrorism powers. The Home Office disagreed and appealed. The Court of Appeal sided with the government.

The Core Legal Dispute

When the government "proscribes" a group under the Terrorism Act 2000, it bans membership, support, and fundraising for that group. People caught breaking these rules face serious prison sentences. The February High Court judgment had said that proscription must be proportionate — meaning if ordinary criminal laws can already address what a group is doing, declaring them terrorists goes too far. That proportionality requirement is what the Court of Appeal rejected.

According to reporting from Al Jazeera, the five judges concluded that Palestine Action's actions looked more organised and dangerous than the group claims. The judges disagreed with the High Court's careful distinction between ordinary crime and terrorism. Instead, they took a wider view of what the Terrorism Act allows the government to ban.

That legal difference has real consequences. Since the proscription took effect, hundreds of people have been arrested on charges related to Palestine Action, BBC News reported in September 2025. Those prosecutions now rest on a terrorist designation that the Court of Appeal has endorsed.

What Happens Next

The case is not necessarily over. Palestine Action could ask the UK Supreme Court — the highest court in the country — to hear the case and settle the proportionality question once and for all. The Supreme Court would decide whether the government has too much freedom to label groups as terrorists without proof that ordinary criminal law would fail.

This matters beyond Palestine Action. Terrorism proscription cases rarely reach court because most banned groups lack the money and public backing to challenge their designation legally. Palestine Action's path through the courts has created a more detailed public record of how judges examine proscription decisions than most other cases produce. If the Supreme Court hears the case, it would set binding rules on how proportionality must work in these situations — rules that would either constrain or give more room to future Home Secretaries when they consider new bans.

The civil liberties group Liberty published a statement the day the ruling came down, flagging worries about what the judgment means for protest rights and freedom of association. Liberty's argument — that proscription criminalises supporting a group rather than punishing specific harmful acts — reflects a wider concern in the UK human rights community: counter-terrorism powers have gradually expanded to cover forms of political protest that fall far outside what terrorism laws were originally meant to address.

That concern is worth taking seriously. The Court of Appeal was deciding only whether the Home Secretary stayed within her legal authority and applied the legal test correctly. The judges were not answering the broader policy question: whether banning a group whose main activities centre on protest-based property damage is the right tool, even if the law technically allows it. That policy debate remains open, whatever the court decided.

The key disagreement between the two courts — about what counts as terrorism, how proportionality should work, and how much deference judges should show the government in these decisions — remains unresolved. Lawyers, activists, and anyone interested in how Britain balances protest rights against national security will be watching to see whether the Supreme Court takes the case.