Insanity defense (potential spoilers)
So after the personality "Roy" is revealed to Vail, Vail talks to his associates and says that it's too late to put in an insanity defense. Okay that makes sense. The thing that bothers me though is it takes a long time to actually get to trial after a crime, even longer when it's murder and longer when it's a death penalty case. Before this case went to trial all of the psych evals would have been completed, so the multiple personality would have been revealed. So of course the insanity defense could have been entered before the trial. Also Aaron would have made sure that his lawyer knew he was "insane" before the trial, he can't take a chance that Vail wouldn't have known in time.
Oh and the judge just deciding on her own that he was insane wouldn't ever have happened. People fake being insane in court all of the time.
Still an entertaining movie, mostly because of Norton's great performance.
Don't play leapfrog with a Unicorn.