From the NYTimes reporting, there’s no indication this person showed any signs of being mentally disturbed, though other news stories have been saying this.

Again, I don’t like guns and choose not to own any, but I also don’t like laws passed after a crime that wouldn’t have prevented the crime in the first place (e.g., “Three Strikes” and numerous “Megan’s Laws”)

If the reports that the shooter had a “personality disorder” are accurate, then the real culprit here is the schoolteacher/mother that kept her legal guns within easy reach of her disturbed son.