Court of Appeal overturns Palestine Action proscription ruling in Home Secretary v Ammori

A Divisional Court judgement that struck down the proscription of Palestine Action lasted less than four months. In The Secretary of State for the Home Department v Ammori [2026] EWCA Civ 721, a five-judge Court of Appeal, led by the Lady Chief Justice, has restored the Home Secretary's decision to proscribe the group under section 3 of the Terrorism Act 2000, in a judgement that will shape how courts approach proportionality challenges to executive national security decisions for years to come.

The case began after the Brize Norton incident in June 2025, when Palestine Action activists damaged two RAF Voyager aircraft. The Home Secretary proscribed the organisation shortly afterwards, relying on assessments from the Joint Terrorism Analysis Centre and Counter Terrorism Policing that pointed to an escalating pattern of property damage, including incidents at Thales in Glasgow, Instro Precision in Kent and Elbit Systems in Bristol.

The Divisional Court had quashed the decision on two grounds. First, it held that the Home Secretary's own proscription policy did not permit her to weigh the "operational benefits" of proscription, such as the additional disruptive powers it confers on law enforcement, because doing so would apply equally to any organisation under consideration. Second, applying the four-stage Bank Mellat test, it concluded that Palestine Action's terrorist activity had not reached the scale needed to justify the interference with Articles 10 and 11 rights that proscription entails.

The Court of Appeal rejected both findings. On the policy point, it found the Divisional Court had read a brief, "open-textured" public information document as though it were a constraining statutory text, when its non-exhaustive list of factors was intended to illustrate rather than limit the Home Secretary's discretion. The operational benefits of disrupting a covert, cell-based organisation "holistically as a network" were, the court held, plainly relevant to the fourth Bank Mellat question of whether a measure's contribution to its objective outweighs its impact on rights.

The more significant correction concerns the margin of appreciation. The Divisional Court had assessed Palestine Action's threat level by reference only to incidents meeting the statutory definition of terrorism, isolated from the organisation's wider conduct. The Court of Appeal regarded this as artificial: an assessment of future risk to national security cannot sensibly exclude the broader pattern of escalation, recruitment, fundraising and the covert operational model described in Palestine Action's own "Underground Manual". Once that fuller picture was restored, and an appropriately wide margin afforded to a decision the court described as falling within the Home Secretary's "special institutional competence", the balance tipped decisively in favour of proscription.

Two further points stand out. The court firmly rejected the argument that Article 17 (abuse of rights) removed the issue from Article 10 and 11 scrutiny altogether, a reminder that even controversial advocacy retains Convention protection unless it meets a genuinely exceptional threshold. And the court gave short shrift to the "emerging international consensus" argument advanced by the UN Special Rapporteur, treating a list of policy criticisms as falling well short of the settled state practice needed to narrow the margin of appreciation under SC.

For practitioners advising on judicial review of national security decisions, the judgement is a clear signal that appellate courts will scrutinise closely any Divisional Court approach that artificially narrows the factual matrix relevant to risk assessment, and that Shvidler-style deference on institutional competence remains robust even where a decision is, on the court's own admission, "borderline". Permission to cross-appeal on procedural fairness and discrimination grounds was refused, leaving the proscription order, and the roughly 700 pending prosecutions linked to it, intact.