Colorado releases 5-year marijuana study on teen use, driving stats

Sam Tabachnik
The Denver Post
FILE - In this Oct. 4, 2016, file photo, farmworkers remove stems and leaves from newly harvested marijuana plants, at Los Suenos Farms in Avondale, Colo. (AP Photo/Brennan Linsley, File)
Associated Press file photo

After five years of data collection, the Colorado Department of Public Safety released its much-anticipated baseline report on the impacts of marijuana legalization.

The data provide glimpses for the first time into the how legalization has impacted several highly-charged subjects, including usage among young people and driving impairment.

The report shows that Colorado has not experienced an increase in marijuana use among young people, although it was the single most common reason for school expulsions in the 2016-17 school year. Marijuana also has not impacted graduation rates or drop-out rates Graduation rates have increased while drop-out rates have decreased since 2012.

Marijuana’s impact on driving is a mixed bag, the report found. The number of fatalities where a driver tested positive for any cannabinoid increased to 21 percent in 2017 from 11 percent in 2013.

However, the percent of drivers who tested above the legal limit of THC decreased to 7.5 percent in 2017 from 11.6 percent in 2016 while the number of citations for marijuana-only impairment stayed steady at around 7 percent over the 5-year time period, the report said. Overall, Colorado State Patrol DUI cases were down between 2014 and 2017.

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