A prison in Washington pairs up "death row" shelter cats with select inmates as part of a rehabilitation program. It seems to be a pretty wonderful thing for both the inmates and the cats.
Inmates are screened very carefully before even being considered as kitty foster parents. First of all, they have to be in jail on nonviolent offences: no crimes against people or animals. While in prison, they have to have a record of consistent good behavior for at least six months.
We hope to see a lot more cat therapy (or any kind of animal therapy) taking place in prisons. It's a win-win situation: it helps inmates feel human, it gives cats a chance to recover from whatever trauma brought them to the shelter.