Abstract
Any reflection on the possibilities of creating a special tribunal to prosecute the crime of aggression in Ukraine should begin by recalling and comparing the existing international and mixed criminal tribunals, as well as the International Criminal Court. Against this background, three basic options are offered.
The first of them is based on the existence of a permanent International Criminal Court, which would ideally be the most appropriate forum. Due to the special, very restrictive regulation of the conditions for the exercise ofjurisdiction over the crime of aggression in the Rome Statute, this is not possible today.
The other two options envisage the creation of a new, special tribunal for Ukraine, which would fill the current gap in the jurisdiction of the ICC. The essential difference and ongoing debates concern whether it would be a purely international tribunal or a mixed (hybrid) tribunal.
While it is not easy to create one of such tribunals when the UN Security Council is blocked, there are alternative ways to do it. In both cases, it can be a combination of a General Assembly resolution and an international treaty.
The proposal to establish an international tribunal appears to be better, although it is still associated with a number of political and legal difficulties. The legal basis could be a multilateral treaty concluded by as many states as possible, including Ukraine, on the basis of recommendation in the General Assembly resolution.
This contribution argues that it is not only an obvious question of the legitimacy of the special tribunal established in this way, but also of its legality.