He was tried under his own laws. That's fair. If he had been tried under, say, the Laws of the United States, with all the legal protections for the Accused; THAT would have been manifestly arrogant and unfair.
ME, I'da just taken him back, around behind the barn, and shot the S.O.B., or dropped a couple a' Grenades down in his little Hidey Hole.
But that's me...I'm eevil.:D