Over the past year, discussions regarding the establishment of a Special Tribunal for the Crime of Aggression (STA) against Ukraine have evolved from debating its necessity to focusing on how best to create such an institution. Two primary options have emerged:
An “international” tribunal created through a bilateral treaty between Ukraine and the United Nations, recommended by the U.N. General Assembly.
Some form of “hybrid” or “internationalized” tribunal that combines elements of both international and domestic legal systems.
On September 22, the Core Group of Friends for Accountability, consisting of 38 States advocating for aggression trials, is scheduled to meet in The Hague, Netherlands, to continue diplomatic negotiations, with the tribunal’s institutional design as a central topic of discussion.
The central question now is which of these two competing models is better suited to address aggression. This decision carries significant implications, as it may determine whether or not Russia’s behavior is subjected to punishment at all. The debate over the tribunal’s institutional design has become increasingly polarized, touching on the core purpose of international criminal justice, especially its role in countering abuses by powerful States.
While various arguments have been made for and against both models, an international tribunal appears to offer greater potential for the development of international criminal law, with some reservations related to in absentia trials. In contrast, opting for a hybrid approach may have conservative effects and potentially enable impunity for powerful nations. Given the gravity of these discussions, proponents of accountability, particularly from smaller and weaker States, should voice their opinions in the coming weeks and months.
The emergence of these two options can be traced back to recent developments. Initially, Ukraine and its allies, particularly Eastern European States, favored an international tribunal following Russia’s invasion. However, major Western powers, starting with Germany and followed by the U.K. and the United States, expressed support for a hybrid tribunal based on Ukraine’s domestic jurisdiction. Ukraine’s stance evolved as negotiations shifted from whether to establish the tribunal to how it should be designed.
In May 2023, Ukrainian President Volodymyr Zelenskyy firmly rejected the idea of a hybrid tribunal, likening it to the flaws of previous Western-imposed arrangements like the 2014-15 Minsk accords, which resulted in only a “hybrid peace.” Ukraine’s preference for an international tribunal faced resistance, leading to public disagreements between Western powers in the G7 and other States forming the Core Group, which includes members from Western States, Eastern Europe, and Latin America. Talks of a compromise solution have arisen, suggesting the use of a third State’s jurisdiction, rather than Ukraine’s, as the foundation for the Special Tribunal’s authority. However, this “third State” model retains some hybrid design features favored by Western powers, such as applying immunities to Russia’s top leadership. This explains Ukraine’s continued advocacy for an international tribunal.
In light of the divergence in views between Western powers and other “Friends of Accountability,” it is essential to examine the main arguments for and against each model before assessing the global implications of this conversation.