Why would do hurt himself? over a dui? doesnt make sense....
When someone is a child prodigy like that, their life isn't the same as everyone elses. It isn't like someone from the local scene that gets a little bit of success at a young age and that is it. I mean Johnny J was huge, he had a lot of pressure on him within his life and a lot of adults at that young age controlling aspects of his situation (which messes you up mentally for life). Imagine being a Youngster and being around Suge Knight at the Hey Day of Death Row.
Now mount on top of all that trying to keep that success you had while you were younger going as an adult. It is pressure. Enough to make a lot of people give up on life and just end it. And you don't have to be weak to do it. Life just gets to people sometimes. He was in jail for D.U.I so that says somethings about his lifestyle at the time right there.
The Entertainment Industry will mess you up man. I started selling songs at the age of 8 years old. Look at Actors like River Pheonix, look at how messed up Cory Haim and Corey Feldman are. Todd Bridges, Dana Platto, Drew Barrymore (was) and even more recently Heath Ledger.
Life is hard enough without having the pressures of having to live up to the industry standards, and when people feel you failed or ask what has he done lately/where is he now, that is just added pressure.
R.I.P Johnny J. You will be truly missed and mourned. God Speed. D.P.G.C.