Discovered recently that Electric Wizard were kinda dicks back in the day. "At the time, we were pretty bad people. I got arrested for arson of a car, outside a police station. Tim [Bagshaw] went to nick a crucifix off a church roof so we could use it onstage..."

R. L. Burnside killed a man "possibly at a craps game."

Varg of Mayhem Burzum burned a couple churches and killed a bandmate.

I could list other examples, but would like to hear from other people and other music genres.