Teen Marijuana Use Does Not Increase Following Marijuana Policy Reforms
Study after study has concluded that cannabis policy reform is not linked to increased rates of marijuana use among teens. As National Institute on Drug Abuse Director Nora Volkow testified at a March 23, 2022 Senate Health, Education Labor & Pensions Committee hearing, “in the United States, legalization by some states of marijuana has not been associated with an increase in adolescents’ marijuana use."
In July 2021, the Journal of the American Medical Association published a major report analyzing federal data from more than 1.4 million high school students.[1] The researchers found no significant associations between the enactment of adult-use legalization laws and marijuana use or frequency of use among high school students. The study also looked at medical cannabis laws and concluded they had no impact on youth marijuana use. These findings were consistent with the results of a meta-analysis of 55 academic papers and multiple data sources published by the journal Current Addiction Reports in September 2018. Those researchers wrote that, “Liberal forms of medical cannabis regulation … have not to date increased rates of cannabis use among adolescents.”[2]
Below are data tables for youth surveys comparing past 30-day marijuana use for high school students before and after adult-use legalization laws passed in the 14 states with before-and-after data. In 13 of the 14 states, government surveys indicate a decrease in teens’ marijuana use rates, a few of which are within the margin of error. In a single state, the surveys suggest a slight increase, within the margin of error. Meanwhile, the CDC’s nationwide survey data shows a modest decrease in teen use since states began legalizing cannabis for adults.
Note: Prior to the COVID pandemic, surveys of high schoolers’ marijuana use before and after legalization indicated no statistically significant changes overall, with a slight decrease as a whole. Results from 2020-2021 indicate more consistent and significant decreases in adolescent’ marijuana use than the previous data. (Of note, in every legalization state other than Massachusetts, adult-use cannabis stores were deemed essential and were not subject to shut-down orders.) It remains to be seen if the 2021 dip was a short-term, pandemic-related change or if it will be more sustained. However, even if the 2020-2021 drop were an anomaly due to the pandemic, the data is clear: legalization for adults does not increase teens3 marijuana use.
Washington State Healthy Youth Survey (past 30-day use) — Law enacted in November 2012 4
2010
2012
2014
2016
2018
2021
8th grade
9.5%
9.4%
7.3%
6.4%
7.0%
2.8%
10th grade
20.0%
19.3%
18.1%
17.2%
17.9%
7.2%
12th grade
26.3%
26.7%
26.7%
26.4%
26.2%
15.9%
Colorado Healthy Kids Survey (past 30-day use) — Law enacted in Nov. 2012 5
2011
2013
2015
2017
2019
2020
2021
9th – 12th grade
22.0%
19.7%
21.2%
19.4%
20.6%
13.3%
13.3%
Oregon Healthy Teens Survey (past 30-day use) — Law enacted in Nov. 2014 6
2013
2015
2017
2019
2020
8th grade
9.7%
8.8%
6.7%
7.8%
3.3%
11th grade
20.9%
19.1%
20.9%
20.4%
13.5%
Alaska Youth Risk Behavior Survey (past 30-day use) — Law enacted in Nov. 2014 77
2013
2015
2017
2019
9th – 12th grade
19.7%
19.0%
21.5%
21.5%
California Youth Risk Behavior Survey (past 30-day use) — Law enacted in Nov. 2016 8
2015
2017
2019
9th – 12th grade
22.9%
21.8%
17.1%
Massachusetts Youth Risk Behavior Survey (past 30-day use) — Law enacted in Nov. 2016 9
2015
2017
2019
2021
9th – 12th grade
24.5%
24.1%
26.0%
16.6%
Maine Youth Risk Behavior Survey (past 30-day use) — Law enacted in Nov. 2016 10
2015
2017
2019
2021
9th – 12th grade
19.9%
18.8%
22.3%
17.1%
Nevada Youth Risk Behavior Survey (past 30-day use) — Law enacted in Nov. 2016 11
2015
2017
2019
2021
9th – 12th grade
19.3%
17.9%
19.8%
16.3%
Vermont Youth Risk Behavior Survey (past 30-day use) — Law enacted in Jan. 2016 12
2017
2019
2021
9th – 12th grade
23.5%
26.5%
19.9%
Michigan Youth Risk Behavior Survey (past 30-day use) — Law enacted in Nov. 2018 13
2017
2019
2021
9th – 12th grade
23.7%
21.5%
14.4%
Illinois Youth Risk Behavior Survey (past 30-day use) — Law enacted in June 201914
2017
2019
2021
9th – 12th grade
20.8%
21.8%
15.1%
Arizona Youth Risk Behavior Survey (past 30-day use) — Law enacted in Nov. 202015
2019
2021
9th – 12th grade
26.1%
19.2%
Montana Youth Risk Behavior Survey (past 30-day use) — Law enacted in Nov. 202016
2019
2021
9th – 12th grade
21.1%
19.7%
New Jersey Youth Risk Behavior Survey (past 30-day use) — Law enacted in Nov. 2020 and Feb. 202117
2019
2021
9th – 12th grade
20.1%
17.3%
Connecticut, Delaware, Maryland, Minnesota, Missouri, New Mexico, New York, Ohio, Rhode Island, and Virginia's legalization laws are too new to have "after" data. They all passed in 2021 or later.
National Survey on Drug Use and Health (past 30-day use, small sample size, no ‘20-’21 data)18
1 Anderson, Mark D., et al. “Association of Marijuana Legalization With Marijuana Use Among US High School Students, 1993-2019”, September 2021. 2 Leung, Janni, et al. “Has the Legalisation of Medical and Recreational Cannabis Use in the USA Affected the Prevalence of Cannabis Use and Cannabis Use Disorders?,” Current Addiction Reports, September 2018. 4 Accessed here: http://www.askhys.net/FactSheets Due to disruptions in education related to the coronavirus pandemic, the survey was not conducted in 2020. 3 Centers for Disease Control and Prevention, “Youth Risk Behavior Survey: Data Summary and Trends Report,” February 2023, p. 22.; "Trends in the Prevalence of Marijuana, Cocaine, and Other Illegal Drug Use National YRBS: 1991—2019," CDC. The last, pre-COVID national figure on current teen cannabis use (21.7% in 2019) was slightly lower than the rate before any state legalized cannabis for adults’ use (23.1% in 2011). 5 Accessed here: http://www.askhys.net/FactSheets Likely due to disruptions in education due to the coronavirus, the survey was not conducted in 2020. The next survey, the Healthy Youth Survey, will be administered in October 2021. 6 Accessed here: https://www.oregon.gov/oha/PH/BirthDeathCertificates/Surveys/OregonHealthyTeens/Pages/index.aspx 7 Accessed here: https://www.cdc.gov/healthyyouth/data/yrbs/results.htm 8 Ibid. 9 Ibid. 10 Ibid. 11 Ibid. 12 Ibid. 13 Ibid. 14 Ibid. 15 Ibid. 16 Ibid. 17 Ibid. 18 Accessed here: https://pdas.samhsa.gov/saes/state (N/A is listed for pre-legalization years) 19 Accessed here: https://nccd.cdc.gov/youthonline/App/Results.aspx?