A study posted by Bryan Caplan suggests so. 2.9% of prisoners in surveyed said they had been sexually abused by a staff member at the prison, while 2% said they had be sexually abused by another inmate.

Not surprising actually given this finding

Girls are disproportionately represented among sexual abuse victims. According to data collected by BJS in 2005-2006, 36 percent of all victims in substantiated incidents of sexual violence were female, even though girls represented only 15 percent of confined youth in 2006.