The root cause is that a huge portion of the US population sees prisons entirely from a punitive point of view. Want to reduce prison sentences? Improve conditions? You're soft on crime!
It seems like there might be room for improving conditions in ways that will help prevent them from being back in prison later. Education and working in a way that develops skills are two ways that come to mind.
Good luck making that argument to the median voter. The entire conservative wing believes prisoners deserve torture (unless it’s them or their immediate family); half of the center-left is too busy projecting a “tough on crime” image to give much thought about improving conditions.
Even if you can prove a non-profit, non-funded program reduces recidivism, if it also happens to make prisoners’ lives marginally better in the process, that’s an immediate no.
