Sad story. Seems to me, though, that over the past 40 years or so, our culture has generally cheapened the value of life. From violent video games, movies, and television shows, to abortion, assisted suicide, and the so-called "complete lives" and "death panels" popularized in current political rhetoric, the idea that life is sacred is something recent generations just haven't gotten. How else do you explain gang bangers looking to "mess someone up" for no ulterior purpose?
Take guns out of it. When I was a kid, all the guys (and some of the girls) at school carried pocket knives. We used them to sharpen pencils, whittle sticks, play mumblety-peg, and carve our initials where they shouldn't be. But not one of us would have thought of using our knives as weapons. My dad used to hitchhike across country. I did some hitchhiking during my college years. I wouldn't consider it at all today, have strongly counseled my kids against it, and in some states, it's illegal. Too dangerous. Something has slipped.
I have reason to be aware of young people whose first run in with the law was a serious offense against persons or property. It would not have appeared that they were "problem kids" prior to the first incident. But each of the cases I am aware of had some history of trauma, in some instances unknown to the parents, that resulted in suppressed memories that came back to haunt the kid. When they couldn't handle it any more, it came out in some unexpected way. I don't know enough to be able to draw conclusions in this case; I have no idea whether there were warning signs or not. But I'm familiar with enough situations first-hand to know that (1) such behavior typically has a cause, and (2) that cause could be something long past and deeply suppressed that the parents know nothing about.
So I say again, this is a sad story. I'm sure the young man has had difficulty. I pray he is able to work through his demons. At the same time, I don't believe prior trauma excuses his behavior, and think he should be tried as an adult. But I say again that I believe there has been a general cultural slippage in the value of human life that is showing up in many places. This seems like one of them.
Oh, and given all the above, my firearms are locked in the safe when not under my direct control or supervision.