It's about the same here. And the fact that Mimi was trying to do the same thing to him wouldn't make any difference. He couldn't claim self-defense, since his "defense" was premeditated. If she'd gone after him with a knife and he killed her in the struggle, then he would have a defense. But the two of them locked in their separate rooms, tinkering with lethal toys to entrap each other -- no winners in that game.