I've done time. A lot of the prison population are as you say. Certain demographics, not so much. It's the exception, not the rule. I've met the brightest and dumbest people I've ever met there.

Truth be told, the staff is usually worse than the inmates. I've seen them killed, beat up, etc for crap they've pulled on inmates. Women's prison, if it's state, isn't much less violent than men's. She's a high value target for the clout alone.