"We can't predict who will re-offend."
Sure we can.
Most who go to treatment against their will, for any reason other than they want to quit using, will use again.
"Most who go to treatment against their will, for any reason other than they want to quit using, will use again."
Actually most who go to treatment for any reason will use again. It takes a long time for hardcore drug addicts to get off of drugs. Just as it is for alcoholics, most try several times before they are successful and some never succeed.
Sending people to a thirty day rehab and then just letting them go without closely monitoring them will never work. Make them do after care and drug test them constantly with punishments for every time they relapse and the success rate will be a lot better.