Why Ukraine Needs an International - Not Internationalised - Tribunal to Prosecute the Crimes of Aggression Committed Against It

Ukraine has called for the establishment of an ad hoc tribunal to investigate and prosecute crimes of aggression committed against it in the context of the Russian invasion. Ukraine has insisted that such a tribunal must be international in nature. Members of the G7, however, have stated that they can only support an “internationalised” or hybrid tribunal embedded in Ukraine’s domestic legal system. This article considers the critiques advanced against the international tribunal model and contends that many of these arguments are flawed, while arguments in favour of the internationalised model are misplaced or overstated. In addition to other advantages, it is demonstrated that an international tribunal: could be set up more quickly; would have a greater prospect of ensuring immunities do not apply; and would be more effective in reinforcing the prohibition of the use of force, thereby maximising the potential of deterrence. For these reasons it is concluded that an international tribunal is the best option for ensuring that those most responsible for crimes of aggression committed against Ukraine are held to account.