Writing in The New York Review of Books, David Kaiser and Lovisa Stannow take a detailed look at the data on sexual abuse in prisons and jails. There's far more in the article than I can summarize in a short blog post, and I recommend you read the whole piece. But this is a passage worth highlighting:
The new studies confirm previous findings that most of those who commit sexual abuse in detention are corrections staff, not inmates. That is true in all types of detention facilities, but especially in juvenile facilities. The new studies also confirm that most victims are abused repeatedly during the course of a year. In juvenile facilities, victims of sexual misconduct by staff members were more likely to report eleven or more instances of abuse than a single, isolated occurrence.
And here is a passage where the authors step away from the statistics and zero in on a particular person's experience:
A.A. is a gay man who had a prior history of being sexually abused—again, the two characteristics that most strongly predict rape in jail—but he wasn't asked about either of these things when he was admitted to the OPP. Instead he was put in a crowded communal cell where he was beaten, choked until he passed out, cut with a knife, masturbated upon, and orally and anally gang-raped by other inmates "so many times I lost count."
There were no security cameras in the cell and no guards around to hear him screaming. He filed grievances claiming that he had been raped, but they went unanswered. ("We dropped the ball on that," said a representative of the OPP at the hearing.) When he finally found the courage to ask a guard for help directly, he was laughed at and told, "a faggot raped in prison—imagine that."