Answer:

The “Gateway Theory” was formulated and promoted by the Drug Enforcement Administration (DEA) for decades touting the theory that marijuana use was a ‘gateway' for consumers to be introduced to and become abusers of harder drugs like heroin, PCP, cocaine, and other illicit substances. That theory was a key propaganda tool to fuel the continued federal prohibition of marijuana cannabis from 1970 to present day. However, in 2014 – DEA abandons the “gateway theory” that marijuana use leads to harder drug use citing that there was and is no statistical basis for that claim that led to the arrest and incarceration of more than one million individuals.