You have to prove that when he is with child, he is not capable of parenting him. If child was a witness to those past events that can hold wait, and his criminal background too. Is child seeing him now? How is it going? When was the last time child saw him? Hold old is child ? All this will come into play. If father plays by the courts rules he will eventually get some time with his child. Courts usually do not care so much about the past, it is what is happening with child now...