The Special Tribunal for the Crime of Aggression Against Ukraine: Jurisdiction, Immunities and Due Process

In June 2025, Ukraine and the Council of Europe signed an agreement on the establishment of the Special Tribunal for the Crime of Aggression against Ukraine. The establishment of the Special Tribunal can with confidence be described a historic development. It is the first ad hoc criminal tribunal created under the auspices of the Council of Europe. The Special Tribunal is likely to become the first international court to prosecute the crime of aggression since the post-World War II trials in Nuremberg and Tokyo. This article focuses on three key aspects of the Special Tribunal. First, it explains the Special Tribunal’s subject-matter, personal, temporal and spatial jurisdiction. Second, the article discusses the provisions of its Statute related to the functional and personal immunities of state officials. Third, the article examines due process guarantees in the criminal proceedings before the Special Tribunal, focusing on the procedure for trials in the absence of the accused (trials in absentia ) and the rules barring repeated trial of the same person for the same conduct ( ne bis in idem ).