I believe the father of the prodigal son would object to the act of giving unrestrained access of an automobile to a fifteen year old. Remember he was a liberal. I have three adult sons none of which was give unfettered access to the family automobile. It was required they show responsibility for their actions with the car, one was arriving home as scheduled. Ask any one of these sons of mine of their parents actions. You will receive an angry reply from each.
On the other hand I wonder why parents go to barber shops with their children and tell the barber how to cut their hair. A part of parenting is watching a child grow within his own self, conforming, rebelling or both. We as parents must learn spiritually when and how to let go. Also we must not allow our children to inflict their immaturity upon the society as a whole. This can only be accomplished via spiritual principles.
Remember the most dangerous unintended acts of violence are committed via inexperienced driving and inexperienced drinking of alcohol