In December 2011, Join Together published a commentary entitled “Legalization of Marijuana and the Impact on Children.” The article stressed that future laws legalizing marijuana use should have strict provisions designed to prevent underage consumption. In the intervening 44 months, four states plus the District of Columbia have legalized the personal use and possession of small amounts of marijuana,[1] the number of states allowing the medicinal use of marijuana for debilitating medical conditions has increased from 16 to 24[2] and 18 states now allow the limited use of low-tetrahydrocannabinol (“THC”) products to treat seizure disorders.[3] Given all this legislative focus on marijuana laws, are we now at a point where we can determine the impact of marijuana legalization on children?

Well, yes and no. In the sense that there is a growing body of scientific evidence, increased research and more recent data, yes. In the sense that the studies are providing clear answers, no.

At least there is some positive news. Two recent studies published earlier this summer using data from the Monitoring the Future program (MTF) suggest that the expansion of marijuana laws has not resulted in increased usage by teenagers.[4] In particular, these studies conclude that:

in the states that legalized the medicinal use of marijuana before 2014, there was no statistically significant change in teens’ (age 13-18) use of marijuana after the law was passed;[5] and
when comparing data from 2002 and 2013, the proportion of younger adolescents (age 12-14) strongly disapproving of marijuana use has increased slightly, while the percentage of teens (both ages 12-14 and 15-17) who have used marijuana in the past 12 months has decreased slightly.[6]

And, when looking at the published MTF data, it appears that the students’ perception of the ease with which they can get marijuana has not changed substantially in recent years (if anything it has lowered) and remains lower than the high water mark in the late 1990s.[7]

There are areas of concern in these and other recent studies, however. The same researchers noted above report that:

although changes in the law did not alter usage, teen use of marijuana is higher in the states that have legalized the medicinal use of marijuana than in other states, suggesting that the usage rate is a product of “state-level” factors that warrant additional study;[8] and
the percentage of adults aged 18-25 who strongly disapprove of marijuana use has dropped significantly in recent years.[9]

Moreover, in data gathered during 2010 and 2011, California students in grades six through eight who had seen marijuana advertising reported that they were twice as likely to use marijuana (or consider using it) than those who had not seen the advertising.[10] Furthermore, since 2000, the number of calls made to U.S. poison control centers concerning marijuana ingestion by children under age six has increased generally, with particular increases in the states that legalized the medicinal use of marijuana during that time.[11]

Although the available research may not yet provide clear answers, lawmakers do seem to be taking heed of concerns about underage access and non-authorized use of marijuana. For example:

only one state that legalized the medicinal use of marijuana after December 2011 allows any form of home cultivation, instead requiring patients to obtain marijuana at state-licensed cultivators/dispensaries;[12]
more recent laws and regulations allowing the medicinal use of marijuana often limit the number of cultivators/dispensaries that will be allowed, sometimes require licensed pharmacists to be involved with dispensaries and routinely place stringent restrictions on who can enter dispensaries and on the packing/labeling/testing of marijuana;
Louisiana, Minnesota and New York exclude smoking from the list of allowable methods to use marijuana medicinally; and
within the past six months, Oregon and Washington have tightened up their regulations concerning the medicinal use of marijuana.

Unfortunately, there is not yet sufficient data from Washington and Colorado to support large scale studies of the impact of legalizing the personal use of marijuana on children in those states. However, once that data develops and researchers have more time to look at it and pre- and post-law change data in all states, it will be important to revisit this question.

Jon Woodruff, Legislative Attorney, National Alliance for Model State Drug Laws

[1] Alaska, Colorado, Oregon and Washington.

[2] The eight states who have passed laws since December 2011 are: Connecticut, Illinois, Louisiana, Maryland, Massachusetts, Minnesota, New Hampshire and New York.

[3] Alabama, Delaware, Florida, Georgia, Iowa, Kentucky, Mississippi, Missouri, Nebraska, North Carolina, Oklahoma, South Carolina, Tennessee, Texas, Utah, Virginia, Wisconsin and Wyoming.

[4] “Monitoring the Future” is an ongoing study of U.S. 8^th, 10^th and 12^th graders’ behaviors, attitudes and values on a variety of topics, including illicit drug use. www.monitoringthefuture.org/. The program started collecting data from 12^th graders in 1975 and data from 8^th and 10^th graders in 1991. The latest year of data available is 2014.

[5] Hasin DR, Wall M, Keyes KM, et al. Medical marijuana laws and adolescent marijuana use in the USA from 1991 to 2014: results from annual, repeated cross-sectional surveys. Lancet Psychiatry 2015; 2: 601–08.

[6] Salas-Wright CP, Vaughn MG, Todic J, Cordova D, Perron BE. Trends in the disapproval and use of marijuana among adolescents and young adults in the United States: 2002–2013. The American Journal of Drug and Alcohol Abuse (posted online July 9, 2015). www.informahealthcare.com/doi/abs/10.3109/00952990.2015.1049493.

[7] See Johnson LD, O’Malley PM, Miech RA, Bachman JG, Schulenberg JE. Monitoring the Future National Survey Results on Drug Abuse 1975-2014: 2014 Overview. www.monitoringthefuture.org/pubs/monographs/mtf-overview2014.pdf.

[8] Hasin DR, Wall M, Keyes KM, et al.

[9] Salas-Wright CP, Vaughn MG, Todic J, Cordova D, Perron BE.

[10] D’Amico, EJ, Miles JNV, Tucker, JS. Gateway to Curiosity: Medical Marijuana Ads and Intention and Use During Middle School. Psychology of Addictive Behaviors June 1, 2015.

[11] Onders B, Casavant MJ, Spiller HA, Chounthirath T, Smith GA. Marijuana Exposure Among Children Younger Than Six Years in the United States. Clinical Pediatrics June 7, 2015. Thankfully, the total volume of calls remains low, with fewer than 2,000 calls total over the 14-year period.

[12] The state is Massachusetts, and a patient is allowed to cultivate marijuana at home only if the overseeing state agency is satisfied that the patient faces hardship in accessing a dispensary.