What I meant was the kid still has a right to know his father. I'm not saying I'd send my kid off unsupervised with him, especially if there's a history of violence, but I'm really disturbed by how often women try to completely cut off a father from their child. There are worse things than getting high and not changing a diaper. , my husband's an excellent father, but he'll let my son wallow around in a poopy diaper until I get back from the store just because he doesn't like changing them.

(Sadly, that's true).
I absolutely agree she has a right to withhold visits... UNTIL she gets the situation sorted out. But if she just cuts him off, she's the one who has to answer to the kid when he's a teenager and starts asking questions about who his father is and how come he's never met him. If it were you, and your mom told you she stopped letting your father see you when you were an infant because you came back from his place smelling like weed and your diaper was wet, how would you feel? This guy may be a royal asshole, but she bred with him and she has a duty to her child to stay connected to him.