carl abul from the spring creek correctional center in alaska. >> there are people with certain criteria, rapos, child molesters. you can't cure them. there's no cure for them. you kill them. that's how you deal with the problem. there's no more problem, then. >> abuhl sentenced to 77 years for murdering a co-worker killed again at spring creek. he says he strangled his cellmate when the man began talking about sexually assaulting female staff. >> why don't you try raping another man? why don't you do that? why you got to rape on a woman? why don't you [ bleep ] try to rape me. i know there's someone out there bigger and badder than me. but, i'm going to die. i'll die for what i believe in. i have a lot of experience. >> a lot of experience in what? >> doing what i do. >> which is? >> taking out the garbage. >> because they so frequently become the prey of inmates like abuhl, most sex offenders live in protective housing units. that's where we met ray rowe. >> it's a big honor badge for general population to kill somebody, especially a sex offender. >> rowe. >> rowe was sentenced to 230