To be honest, i think he will get off. He has pulled out the "mentally unstable" card.
That claiming insanity shit is fucking bullshit in my eyes. Not that he isn't mentally unstable, but they can't just let him go because of it. Send him to a hospital, right where everyone like him belongs. Previous court rulings will help his side of the situation, but i hope to god that he doesn't go back out into society soon. Too much feeling sorry and excusing them for their "helplessness".