The June 17th issue of The Marijuana Report summarized a new study, published by Lancet, that finds marijuana use does not increase among high school students when a state legalizes medical marijuana. Researchers analyzed data from the Monitoring the Future Survey about past-month marijuana use among 8th, 10th, and 12th grade students between 1991 and 2014.
Although use does not increase after legalization, a key finding of the study—ignored by most of the press—is that use was already higher in states before such laws were passed than in states that have never legalized medical marijuana.
The question is why? What is different about these states from states that haven’t legalized medical pot?
“These states might differ from the others on common factors yet to be identified (eg. norms surrounding marijuana use or marijuana availability),” say the researchers. “Investigation of these factors is warranted.”
There is no doubt that nationally, taking all states together, marijuana use increased dramatically between 1991 and 2014. As shown in the above graphic, past-month use doubled among 8th graders, nearly doubled among 10th graders, and increased more than 50 percent among 12th graders.
The Marijuana Reports states, “We need to understand what drove these increases.”
At the same time, the perception that regular marijuana use is harmful decreased among 8th graders from 83.8 percent in 1991 to 58.9 percent in 2014, among 10th graders from 82.1 percent to 45.4 percent, and among 12th graders from 78.6 percent to 36.1 percent. Why so many high school students believe regular marijuana use is harmless also needs to be understood so that this misperception can be corrected.
Read Lancet study here.
See Monitoring the Future past 30-day marijuana use data here.