. >> the crime rate in the historic town of fort madison, iowa, is almost nonexistent. and yet many of the state's most violent offenders call this small town home, sort of. they live at the iowa state penitentiary. behind this maximum security facility's 40-foot stone and concrete exterior is a population of drug abusers, murderers, and the mentally ill. on the west bank of the mississippi river is one of the oldest prisons in the country, iowa state penitentiary. there is a separate facility at iowa state penitentiary called ccu, the inmates who are considered mentally ill are housed here. lieutenant john fedler oversees the correctional staff at ccu. >> the staff have been through specialized training to be able to deal with the mentally ill inmates. >> up to 200 men can be housed in ccu. most of them reside in single cells in one of the four general population pods. >> i am here for depression. i was out on work release. i escaped from a work release center because i couldn't find a job. i robbed a bank in my hometown where the work release center was. i got in a hi