And by the way I'm not just talking about non-violent drug offenses. Armed robbery, simple assault, manslaughter, negligent homicide and all the other violent crimes that can carry a prison sentence but not for the rest of your life. I think there are two things you could do with these people.
A.) Become more draconian. Because going to prison makes them more likely to commit a crime when they get out, let's never let them out. Life sentence without parole for any violent crime.
B.) Create a new network of correctional facilities that would be vastly different from what we know of today as prison. Zero tolerance for all the bullshit that is for some reason just allowed to go on in real prison (violence, gangs, intimidation/coercion, sexual assault/rape). Anyone who tries to turn these rehab facilities into real prison gets to go there himself for a very long time. The new correctional facilities for non-lifers is a safe place that encourages personal growth, contrition for your past crimes, and preparation for re-entering society as a changed person. Along with this would have to come an aggressive public campaign to characterize such facilities very differently from what society thinks about prison. It's essential to removing the stigma that comes with having served jail time. If you apply for a job and have to explain your criminal record, you explain that after a regrettable incident, you spent some time a Rehabilitative Correctional Facility, not a penitentiary, and found it very helpful in turning your life around.
Meh. Those dickhead employers would probably still trash your resume immediately but maybe over a few generations the attitude changes.