Right now, Iowa and most jurisdictions deal with drug abuse almost exclusively through law enforcement. If you're caught with a prohibited drug, or one you don't have a prescription for, you can be arrested, charged and convicted of a criminal offense. In most cases, that means you'll be incarcerated -- with little to no access to drug treatment.
The idea of parole and probation was to reduce the number of people in prison, but states are spending millions on incarcerating people for technical violations of their supervision agreements. In Iowa, for example, 40% of the prison population is made up of parole and probation violators. And, 56% of all new prison admissions are for supervision violations -- 22% of them technical violations.