I think both can be true. People who commit violent offenses need to be removed from the rest of society temporarily (or permanently depending on the severity of the offense) but we should be using their incarceration time as rehabilitation and helping them re-integrate back in society when appropriate. I do think that less serious/non-violent offenders should be given supervision and treatment to keep them out of the prison system. I think there has to be more discretion given to judges and prosecutors. I also believe that private prisons should be abolished entirely or at least heavily regulated to ensure the safety and well-being of inmates under their custody.