While I do agree that it was the law enforcement agencies job to ensure the child safety, and they are totally at fault for his death, I do not agree on the parents actions.
I did some stupid stuff when I was a kid, and I even got arrested because my mother called the cops on me. She did not, however, press charges and have me set to prison. The parents failed, whether it was prior to this by not giving him proper discipline, or this time by chosing prison for him. I don't care how bad a kid gets, prison at 17?!? For taking the car without permission?!? That's parents who got lazy, nothing more. They let the state do their parenting instead of handling it themselves. Control of a child is easy, you provide EVERYTHING. Simply cut them off, no money, no car (hello!? lock up the keys), stop buying soda for the house, cut off everything they know and love and take for granted. There's always a solution, parents have been dealing with kids forever, but proxy-parenting via the state is BS and a cop-out.
E1