All members of the ethnic group in the whole former Yugoslavia? In the relevant republic? The number of combatants? Or would you expect the number of indictees to be independent of the size of the ethnic group? How about proportionality to the number of dead civilians in other factions, etc?

All this for an unbiased court. You can then quantify the deviations from the model.

Most economists teach a theoretical framework that has been shown to be fundamentally useless. -- James K. Galbraith