High schooled

A new study has found that medical-marijuana laws do not cause a rise in teen marijuana use—and, in fact, teen use drops when new pot laws hit the books.

Researchers D. Mark Anderson, Benjamin Hansen and Daniel I. Rees, working with funds from the Institute for the Study of Labor in Europe, published their findings as a discussion paper in May.

The team looked at national and state surveys of teen drug use from 1993 onward, and estimated the relationship between medical-marijuana laws and teen-marijuana use. They found that the results were not consistent with allegations made by the U.S. government and others that medical-marijuana legislation—also called MML, laws regulating or legalizing medical cannabis—was leading to more kids using pot.

First of all, kids used pot well before there was medical marijuana: Though it’s been around for thousands of years and use peaked in the ’70s, for decades about 71 percent of teens have consistently said that weed was easy or somewhat easy to get.

Two studies, from 2011 and 2012, tried to directly correlate medical-pot laws with teen use. The 2011 study found teen marijuana use higher in states that had medical-pot laws, but the study noted that “in the years prior to MML passage, there was already a higher prevalence of use and lower perceptions of risk.” Conversely, the 2012 study found “that legalization was associated with a small reduction in the rate of marijuana use among 12- through 17-year-olds.”

In this study, researchers looked at youth behavior surveys from 1993 to 2009 in 13 states that had legal medical pot, finding that “the legalization of medical marijuana was not accompanied by increases in the use of marijuana or other substances such as alcohol and cocaine among high-school students.

“Interestingly, several of our estimates suggest that marijuana use actually declined with the passage of MMLs.”

The researchers then double-checked their findings using other survey sources, adding: “Legalization of medical marijuana is associated with a 7.4 percentage point decrease in the probability of marijuana use within the past 30 days, and a 4.4 percentage point decrease in the probability of frequent use.”

Researchers note their findings directly contradict the demonization of medical marijuana by U.S. attorneys in California and other hardened drug warriors.

The study states: “Our results are not consistent with the hypothesis that the legalization of medical marijuana caused an increase in the use of marijuana and other substances among high-school students. In fact, estimates from our preferred specifications are consistently negative and are never statistically distinguishable from zero.”