Researchers Debunk the Gateway Theory … Again

For decades, prohibitionists have claimed that marijuana is a “gateway drug” that inevitably leads to use of harder substances like heroin and cocaine — despite the fact that every objective study ever done on the gateway theory has determined that it’s absolute crap.

Last week, researchers at the University of New Hampshire released yet another study discrediting the gateway theory. Their findings, based on survey data from more than 1,200 students in Florida public schools, showed that a person’s likelihood to use harder drugs has more to do with social and environmental factors than whether or not they’ve ever tried marijuana.

"There seems to be this idea that we can prevent later drug problems by making sure kids never smoke pot," lead researcher Dr. Karen Van Gundy, associate professor of sociology at UNH, told CBS News. "But whether marijuana smokers go on to use other illicit drugs depends more on social factors like being exposed to stress and being unemployed - not so much whether they smoked a joint in the eighth grade."

These findings echo virtually every other previous study done on the topic. In 2008, for example, the RAND Corporation found that “[t]he gateway theory has little evidence to support it, despite copious research,” and the federal government’s own Institute of Medicine, in a report commissioned by the drug czar’s office, has declared that “[t]here is no evidence that marijuana serves as a stepping stone [to other drugs] on the basis of its particular physiological effect.”

In a news release last week, the UNH researchers urged American drug policy makers to reconsider current penalties in light of their findings. “Employment in young adulthood can protect people by 'closing' the marijuana gateway, so over-criminalizing youth marijuana use might create more serious problems if it interferes with later employment opportunities,” Van Gundy said.

Of course, no one should expect these findings to have much of an impact on prohibitionists’ rhetoric, since that would require them to acknowledge, well … reality. But it was encouraging to see this study reported in such mainstream news outlets as The Los Angeles Times, Business Week, and CBS News. The next time some dishonest prohibitionist tries to call marijuana a gateway drug in print or on the air, any reporter or anchor worth their salt should be able to point out that there isn't any scientific evidence to support the gateway theory. But maybe that’s wishful thinking.