I first want to say there are NO excuses for things he may have done as an adult, period.
Did anyone see that special where he was interviewed about when he was first joining the family as a performer ?
The interviewer asked him about the family's rehearsal's, he said if they missed a step or did not sing just right his father would beat them. He was crying and was not acting he was/is afraid of his father. He said we were beat with what ever was there that his father would pick up, they were thrown against the wall, kicked and beat until they would be bleeding and have bruises. He was asked what his mother would do, not much but she did try to stop him screaming "your going to kill him stop" but she could not stop him. MJ said look at any of the TV programs when they first started preforming on TV, he said were all terrified our father would think we could have done better because we knew what would happen when we got home.
From the way he talked he was still scared of him and did not care if he ever seen him. Whatever MJ did in the rest of his life is on him, but I guess back then people got away with doing things like that to kids, he used the kids to make a living after he singing career failed, he said they would get the family out of that town if it killed them.