Earlier quoted context omitted.
This is a strange reply. What makes you think that that is what the poster to whom you reply is concerned about? People don't commit violent crimes for weed . The crime is having weed . And things that are not weed are not being legalized state-by-state.
The subject is analyzing prison's role in rehabilitation. If we consider prison a failure as a rehabilitation device, then maybe we should focus on rehabilitation before prison. This is a reasonable suggestion. However, if the reason they're in prison is for drug possession, which makes up a huge portion of the prison population, I'm suggesting that any kind of rehabilitation is nearly impossible. With cannabis legal…
But we also have very high recidivism rates for stuff like "armed robbery", independent of social-issue crimes like marijuana possession. And society generally has an Opinion about armed robbery. (It's bad!)