paul payne has a track record. not just violence. chronic, terrible violence. >> thomas headley is in unita-1 for his own protection. >> because i was a member of the mormon church and a sex offender. this individual decided he was going to beat the living crap out of me and in the process of it, decided he was going to kill me. >> he is serving 15 years. >> they have been holding me in the section that they're in right now, because i absolutely refuse to be housed among people that are going to cause me harm. >> about a quarter of usp's 4,000 inmates are sex offenders. most, like thomas, have been targeted for their crimes. >> we're constantly finding them assaulted. we're constantly finding them extorted. >> i've got a safety list that's got at least 20 names on it with people that told me in no uncertain terms, you're a dead man if we ever get our hands on you. i admitted to have improper sexual relationship with this girl. she was 14. i am a man that is attracted to young women, god forbid. i have 16 months left to go. and all i'