[New report] The Special Tribunal for the Crime of Aggression Against Ukraine: Legal assessment and policy recommendations
Published 25 June 2025
The Asser Institute's new report on the Special Tribunal for the Crime of Aggression offers the first legal analysis of the tribunal and its legal and policy considerations.
Today, 25 June 2025, Ukraine's President Volodymyr Zelenskyy and the Secretary General of the Council of Europe Alain Berset signed the historic agreement to establish a Special Tribunal for the Crime of Aggression against Ukraine within the framework of the Council of Europe in Strasbourg. This marks the first time in history that a dedicated tribunal is being established to investigate and prosecute the crime of aggression.
The Asser Institute is now releasing a Report on the Special Tribunal, which offers the first legal analysis of the 'Council of Europe model,' as well as broader legal and policy considerations. It contains contributions from Dr Gabrielė Chlevickaitė, Dr Kateryna Busol, Prof. Frank Hoffmeister, and Dr Owiso Owiso.
The newly-signed agreement is the result of long work by the Core Group on the Special Tribunal for the crime of aggression against Ukraine ('Core Group'), an informal gathering of state representatives, which has been meeting since January 2023 to find an appropriate legal response and assess the options of international, hybrid, and other tribunal models.
Foundational legal documents
After fourteen meetings, in May 2025, the work of the Core Group was declared completed, with the finalisation of the foundational legal documents of the Special Tribunal. The final model designed in the Core Group was inspired by the role played by the Council of Europe in the setting up of the Register of Damage for Ukraine.
The draft legal texts (the statute, enlarged partial agreement, and rules of procedure and evidence) were endorsed by Foreign Ministers of the Core Group on 9 May 2025, in Lviv. The draft texts were forwarded to the Council of Europe on 14 May, culminating in today's historic signing.
The novelty of the Tribunal, to be established on an unprecedented legal framework, is an opportunity for comprehensive legal assessment. It also calls for engagement with broader themes of accountability, legitimacy, and future prevention of aggression, all covered in the Report. It further calls for a reinvigorated effort to ensure that the limited jurisdiction of the International Criminal Court (ICC) over the crime of aggression is aligned with the other core crimes under the Rome Statute, to lower the chances that another tribunal of such nature is needed in the future.
The ICC Assembly of States Parties are meeting at a special session to review the amendments on the crime of aggression on 7 and 9 July 2025, presenting a key opportunity to address these jurisdictional gaps.