While mental health might sometimes play a crucial role in violent outbursts, in this instance the killer's family is trying to lay the blame at the feet of Asperger's Syndrome (recently renamed "autism spectrum disorder"). I know quite a bit about Asperger's and there is nothing about it that can account for this sort of planned, deliberately lethal attack. And I ascribe no shame to any sort of mental or developmental problem; I'm bipolar myself. Sorry to be preachy.