Sorry, I cannot buy into a conspiracy theory here. A young man that will murder his own mother, along with 26 people we assume unknown to him is obviously disturbed in ways I cannot comprehend. As our society cheapens life through abortion, the morning after included, along with talk of "should the elderly receive expensive medical options", we have lost respect for God given life.
No amount of legislation can make crazy people sane, nor can it protect us from these events. In Japan, there were two events in the last 3 years where multiple school children were killed with both a truck and a knife.
The best answer is for parents to reinforce in their young ones the sanctity of life, and TAKE AWAY THOSE VIOLENT VIDEO GAMES.
Just my opinion.
Ben