By Miriam Boeri 4/25/15 at 3:03 PM
With states legalizing marijuana by popular vote, some politicians, including Boston mayor Marty Walsh and New Jersey governor Chris Christie, are still calling marijuana a gateway drug.
The gateway theory argues that because heroin, cocaine and methamphetamine users often used marijuana before graduating to harder drugs, it must be a “gateway” to harder drug use. The theory implies that there is a causal mechanism that biologically sensitizes drug users, making them more willing to try—and more desirous of—harder drugs.
Yet the gateway hypothesis doesn’t make sense to those who use marijuana or have used in the past. Research shows that the vast majority of marijuana users do not go on to use hard drugs. Most stop using after entering the adult social world of family and work.