The issue is not so black and white. Intervention and interning addicts in rehab centers is a very effective program for Rhode Island. They prosecute drug crimes and misdemeanors, and offer a choice between prison or enforced rehab. Many people who go through the program say it saved their life, and they come out with no criminal record.
West coast states have similar alternative drug courts and rehab available, but they are underutilized because there is no incentive. Even non-drug misdemeanors committed by addicts are ignored.
Why do you think it is very effective in Rhode Island? Oklahoma, which I think pioneered the concept of a special drug court for forced rehab, has maybe a 10% success rate.
West coast states have similar alternative drug courts and rehab available, but they are underutilized because there is no incentive. Even non-drug misdemeanors committed by addicts are ignored.