The Secretary of State for the Home Department v Ammori, R (on the application of)

Factual and Procedural Background

The Respondent, a co‑founder of an organisation referred to in this summary as "Organization A", challenged the Appellant's decision to proscribe Organization A under section 3 and schedule 2 of the Terrorism Act 2000 (the "Proscription Decision"). The Proscription Decision was announced to Parliament on 23 June 2025 and the implementing order came into force on 5 July 2025.

Organization A had engaged in a nationwide campaign of direct action against corporate and institutional targets, including three incidents identified by the courts as causing serious damage to property. Organization A published an operational document (the "Underground Manual") describing covert cell structures, reconnaissance and tactics including use of sledgehammers and other means to cause property damage.

The Divisional Court (Judge Swift and Judge Steyn) quashed the Proscription Decision in February 2026, upholding two grounds: (i) that the Appellant had breached her own Proscription Policy by taking into account certain "other factors" (notably operational benefits of proscription); and (ii) that the Proscription Decision was disproportionate as an interference with Articles 10 and 11 ECHR. The Appellant was granted permission to appeal and the Divisional Court stayed its quashing order.

The Court of Appeal (panel delivered by Judge Carr with Judges Vos, Edis, Lewis and Whipple) heard the appeal and, after an open judgment (and a closed judgment on closed materials), allowed the Appellant's appeal, set aside the quashing order and refused the Respondent permission to cross‑appeal on the Procedural Fairness and Discrimination grounds.

Legal Issues Presented

1. Whether the Appellant lawfully applied the Proscription Policy when deciding to proscribe Organization A (the Policy Ground).
2. Whether Article 17 ECHR prevented Articles 10 and 11 from being engaged in respect of expressions of support for Organization A.
3. Whether the Proscription Decision was a proportionate interference with Articles 10 and 11, applying the four‑stage test in Bank Mellat v HM Treasury (No 2).
4. Whether procedural fairness required the Appellant to give Organization A an opportunity to make representations before laying the proscription order before Parliament (Procedural Fairness Ground).
5. Whether the Proscription Decision was unlawfully discriminatory contrary to Article 14 read with Articles 10 and 11 (Discrimination Ground).

Arguments of the Parties

Appellant's Arguments

• The Proscription Policy did not restrict the Appellant from taking into account operational benefits of proscription; the list of factors is non‑exhaustive and the Appellant lawfully considered operational impact and future risk.
• Article 17 should exclude from protection under Articles 10 and 11 any expression or association amounting to support for an organisation engaged in terrorism.
• The Divisional Court failed to afford the proper margin of appreciation to the Appellant on matters of national security; the decision was within the Appellant's institutional competence and democratically accountable judgment.

Respondent's Arguments

• The Appellant breached the Proscription Policy by relying on operational consequences that the Policy did not permit, and thus acted unlawfully in applying the Policy.
• The Proscription Decision was disproportionate under Articles 10 and 11 because only a small number of Organization A's actions amounted to terrorism and less intrusive measures (civil remedies or ordinary criminal prosecutions) were available.
• The Appellant acted unlawfully by failing to give Organization A an opportunity to make representations before proscription (Procedural Fairness Ground) and the decision was indirectly discriminatory contrary to Article 14 (Discrimination Ground).

Interveners' Arguments

• Interveners (including the United Nations Special Rapporteur, Amnesty and Liberty) submitted that there is an emerging international consensus that proscription of groups of this type is disproportionate and that a narrower margin of appreciation should be applied; they emphasised risks of chilling effect on lawful protest and fundamental importance of Articles 10 and 11.

Table of Precedents Cited

Court's Reasoning and Analysis

The court proceeded in the following stages.

1. Interpretation of the Proscription Policy: The court held that the Policy is a broadly framed public information document whose enumerated factors are non‑exhaustive. The Policy did not limit the Appellant from taking into account "other factors" such as the operational benefits of proscription in a particular case. The Divisional Court's narrower interpretation was rejected as excessively analytical.
2. Article 17: The court held that Article 17's threshold is high and applies only in extreme cases. Many aims of Organization A (opposition to certain foreign policy actions) are not acts aimed at destruction of Convention rights. Article 17 did not preclude Articles 10 and 11 being engaged (the "chilling effect" on peaceful protesters remained a relevant consideration).
3. Approach to proportionality and standard of review: Citing Shvidler and Bank Mellat, the court decided to undertake the four‑stage Bank Mellat proportionality analysis afresh rather than simply review the Divisional Court, because of the case's major social and political significance.
4. Margin of appreciation: The court recognised and accorded a wide margin of appreciation to the Appellant on national security matters, emphasising executive institutional competence and democratic accountability, but noted that the court remains ultimate arbiter.
5. Application of Bank Mellat tests:
• Importance of objectives (stage 1): The court accepted the legitimate aims (protection of rights of others and national security) as sufficiently important.
• Rational connection (stage 2): The court found the Proscription Decision rationally connected to those objectives on the evidence (assessments from Agency A, Police Unit A and the Review Group).
• Less intrusive measures (stage 3): The court concluded there were no satisfactory less intrusive measures. Ordinary criminal prosecutions, civil remedies or targeted orders would not achieve the holistic disruptive effect proscription would provide, and the Appellant had considered these alternatives.
• Fair balance (stage 4): The court balanced the significant interference with Articles 10 and 11 against the community interests and future risk. It placed weight on Organization A's covert cell structure, the Underground Manual, the escalating trajectory of damaging activity, attacks on key infrastructure and impact on third parties, and on the operational benefits of proscription. Affording appropriate deference, the court concluded the Appellant struck a fair balance and the interference was proportionate.
6. Procedural Fairness and Discrimination cross‑appeal: The court found the Terrorism Act 2000 impliedly excludes a duty to consult a suspected terrorist organisation before proscription and, in the circumstances, no unfairness required prior representations. On discrimination, the court found no evidence that Organization A was treated differently from materially analogous groups or that proscription had a disproportionate adverse impact on a protected group; the Article 14 complaints had no realistic prospect of success.

Holding and Implications

APPEAL ALLOWED; QUASHING ORDER SET ASIDE; PROSCRIPTION ORDER UPHELD.

Direct effects: The Court of Appeal allowed the Appellant's appeal, held that the Proscription Decision was lawful, set aside the Divisional Court's quashing order and refused the Respondent permission to cross‑appeal on Procedural Fairness and Discrimination grounds.

Implications: The decision reinstates the Proscription Order in respect of Organization A and confirms that (i) the Proscription Policy is not a limiting instrument preventing consideration of operational benefits, (ii) Article 17 does not automatically exclude Articles 10 and 11 in this factual context, and (iii) courts should afford a wide margin of appreciation to the executive on national security matters while retaining ultimate supervisory authority. The court applied established authorities and did not indicate the setting of a novel legal precedent beyond application of existing principles.