Be there to help him out by just being his friend, and most important remember you cannot change him, no one can. Only he can change his self, and that will only happen when he is ready to do it, I had a son who was a delinquent, out of three kids, he was the hardest, but now he is the best one out of the bunch, because he finally decided to make his changes on his own, and I was there to support him when he was doing good. I did not support the bad, and made that clear to him that he was not welcome around me, while he was high or drunk.