Why are politicians still referring to marijuana as a gateway drug?

A myth ingrained in politics, perpetuated through policy
20 April 2015
Other news

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.

Most of the research linking marijuana to harder drug use comes from the correlation between the two. However, as any junior scientist can tell you, correlation does not mean causation. On the periphery of the marijuana-as-gateway-drug debates are studies showing marijuana as beneficial for the treatment of opiate addicts. These have been largely ignored.

The Conversation (US)
Monday, April 20, 2015