Researchers like Timothy Leary felt psychedelics could alter the fundamental personality structure or subjective value-system of an individual to great potential benefit. Beginning in 1961, he conducted experiments with prison inmates in an attempt to reduce recidivism with short, intense psychotherapy sessions. Participants were administered psilocybin during these sessions weeks apart with regular group therapy sessions in between.[24] Psychedelic therapy was also applied in a number of other specific patient populations including individuals with alcoholism, children with autism, and persons with terminal illness.[24]

Studies on medicinal applications of psychedelics ceased entirely in the United States when the Controlled Substances Act was passed in 1970. LSD and many other psychedelics were placed into the most restrictive "Schedule I" category by the United States Drug Enforcement Administration. Schedule I compounds are claimed to possess "a high potential for abuse and the potential to create severe psychological and/or physical dependence" and have "no currently accepted medical use",[28] effectively rendering them illegal to use in the United States for all purposes. Despite objections from the scientific community, authorized research into therapeutic applications of psychedelic drugs had been discontinued worldwide by the 1980s.

Can't have prisoners being reformed when they can be rented out as ditch-diggers for less than minimum wage. Just don't call it slavery.