School shootings are no accident. The shooters prepared, aquired weapons and trained. At some point they made a decision to kill. The question about that decision is never asked. There has to be a reason or 100 reasons but there has to a reason. The problem is that these killers usually don't survive so asking them is not a option. But there are many murderers in prison including multiple murderers who could still be used to investigate why humans murder. It's easy to call people crazy and monsters and they may very well be but there is a foundation to their mindset.