Mock trial for lord of the flies. Prove jack is guilty?

The insanity defense is a very powerful legal tool. The way to counter it is to prove that at the times of the incidents (i.e. quotes) that a) Jack was fully aware that what he was doing was wrong; b) that Jack performed the guilty action (actus reus); and c) that Jack understood that his actions were against the law (mens rea). That's the basics--you can't rely on the internet to do all of the work for you, but that's a definite start.