According to a new study published in the journal JAMA [Journal of the American Medical Association] Pediatrics, marijuana legalization not only doesn’t increase teen usage rates, but it may also actually decrease them.
For the study, researchers examined survey data on substance use collected from 1.4 million adolescents between 1993 and 2017, reports Reuters. During that period, 27 states and Washington, D.C. legalized medical marijuana and seven states legalized cannabis for recreational purposes. The study found that while medical marijuana laws didn’t appear to influence whether teens used marijuana, recreational marijuana laws were actually associated with an 8% decline in the odds that teens would report trying marijuana in the previous 30 days and a 9% decrease in teens reporting frequent use.
Reduced supply may explain why, said lead study author Mark Anderson, an associate professor in agricultural economics at Montana State University in Bozeman.
“It may actually be more difficult for teens to obtain marijuana as drug dealers are replaced by licensed dispensaries that require proof of age,” Anderson said by email. “Selling to minors becomes a relatively more risky proposition after the passage of these laws.”
It’s possible legalizing marijuana leads more parents to talk to kids about the risks of drug use, said Rebekah Levine Coley, a professor of developmental and educational psychology at Boston College who wasn’t involved in the study.
These laws may lead to “increased parental supervision or discussions between parents and adolescents regarding the dangers of marijuana use in reaction to legalization and the resultant increases in political and news attention and perceived availability,” Coley told Reuters in an e-mail.
For these conversations to have the intended effect, parents need to listen, not just lecture, said Dr. Ellen Rome, head of the Center for Adolescent Medicine at Cleveland Clinic Children’s in Ohio.
“Have frank discussions with your teen, where you ask first what they believe about teens and marijuana use before and after legalization,” Rome, who wasn’t involved in the study, said by email. “Then share your own beliefs, and encourage dialogue – and ask what they believe will help prevent youth from using illegally.”
According to a study published earlier this year in The Journal of Adolescent Health, the legalization of marijuana in Washington State is not associated with an increase in marijuana use by most teens. The study found that “marijuana use decreased significantly among working and non-working 8th and 10th graders.” Marijuana use similarly declined among 12th graders who were not employed, while among 12th graders who were employed more than eleven hours per week marijuana use actually increased over the study period, though just slightly. The study’s authors acknowledged that this latter finding was not unexpected because “the workplace may expose adolescents to peer or adult coworkers’ potentially unhealthy behaviors, including substance use.” Authors further acknowledged that working youth were also more likely to have reported using cannabis prior to the passage of legalization.
The full text of the study, titled “Employment and marijuana use among Washington state adolescents before and after the legalization of retail marijuana,” appeared in The Journal of Adolescent Health.