Putin isn't likely to face a war crimes trial, but courts have other options

“My best bet, and I think the great promise of international justice for abuses in Ukraine, is going to be European courts” using the universal jurisdiction doctrine to prosecute Russians, Zvobgo said.

Universal jurisdiction is the legal concept that a country’s domestic court system can take up cases against people who are accused of committing grievous offenses, such as war crimes and genocide, even if the alleged crime happened outside of the prosecuting country’s territory. The rationale behind the idea is that the authority and duty to prosecute serious crimes extends beyond international borders because people who commit such acts are deemed hostes humani generis — “enemies of all mankind.”

The doctrine was used when Spanish courts tried dictator Augusto Pinochet, over abuses when he ruled Chile; more recently, it allowed a German court to sentence a Syrian intelligence officer to life in prison for murders and torture that took place in Damascus…

Another approach to hauling Russians into court would be for the U.S. and its allies, such as France, U.K. and Germany, to try to create an ad hoc international tribunal outside of the U.N., similar to the Nuremberg and Tokyo war crimes trials. But such an undertaking would pose a number of challenges — including questions of legitimacy, in Zvobgo’s view.