Yep, if I was representing someone who had committed a violent crime, that would probably be my defense too. If there are people stupid enough to hold him less responsible for his actions because he'd heard of a video game, more fool them for letting him get away with it. One day we might learn that it's our newfound love for finding ways to justify violent crime that is responsible for the rise in said crimes, but until then, we'll just keep looking for the easy answers and letting it get worse.