Changes In State Marijuana Laws Associated With Declining Teen Use.
CDC data reports that the percentage of high-schoolers ever reporting having used cannabis fell from an estimated 43 percent in 1995 to just under 39 percent in 2015. The percentage of teens currently using cannabis (defined as having used marijuana at least once in the past 30 days) also declined during this same period, from 25 percent in 1995 to just under 22 percent in 2015.
During this time period, two-dozen states enacted statutes permitting qualified patients to consume cannabis, and four states enacted laws permitting the commercial production and retail sale of marijuana to adults.
The Youth Risk Behavior Survey results are consistent with those of numerous other studies — such as those here and here — finding that changes in cannabis’ legal status are not associated with increased use among adolescents.