The Agreement between the Council of Europe and Ukraine establishes a Special Tribunal to prosecute individuals bearing the greatest responsibility for the crime of aggression against Ukraine. Adopted in June 2025, the treaty-based tribunal responds to Russia’s use of force beginning in 2014 and escalating in 2022. The Tribunal’s Statute explicitly removes head of state immunity, ensuring that senior leaders may face prosecution. Jurisdiction is limited to aggression as defined by UN General Assembly Resolution 3314. The institutional framework includes chambers, a prosecutor’s office, and a registry, with robust fair trial guarantees. This represents a significant development in international criminal justice and accountability for leadership crimes.

On July 25, 2025, the French Court of Cassation handed down an important decision concerning the existence in international law of possible exceptions to the functional immunity of agents of a foreign state. The Court of Cassation reached the conclusion that the “principle of functional immunity from jurisdiction in criminal matters” recognized for foreign agents acting in the exercise of their functions cannot be invoked in cases of prosecutions for genocide, crimes against humanity, and war crimes. However, the Court’s internationalist approach, which sought to identify the evolution of custom on the issue by examining relevant state practice, remains exclusively Eurocentric, by examining the practice of only five states, all from the same region of the world.