New data from the Centers for Disease Control and Prevention shows about 12 million Americans operated a vehicle while under the influence of marijuana.
Based on a survey of almost 48,000 people in 2018, 4.7 percent of Americans 16 years or older reported saying they drove while high on cannabis during the last year. The most recent data prior to this study came in 2014 when a Substance Abuse and Mental Health Services Administration's survey found 3.2 percent of persons aged 16-25 drove under the influence of marijuana.
Those answering yes to the question “During the past 12 months, have you driven a vehicle while you were under the influence of marijuana?” were more likely to be men between the ages of 21-25 years, with the second-highest coming being a younger age group at 16-20. It's that second group that researchers are particularly concerned about due to marijuana's influence on a still-developing brain, and the relative inexperience of drivers at that age.
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The uptick in usage while driving follows a building momentum of marijuana legalization across the state, with Michigan being one of the most recent additions to that list. Currently, 11 states and the District of Columbia allow for the recreational use of marijuana by adults 21 years or older.
The survey also found 2.3 million participants said they had driven under the influence of other illicit drugs like cocaine, meth, and opioids like heroin.
Data from trauma centers in Arizona between 2008-14 show 10 percent of drivers aged 16-20 that were injured from vehicle crashes were under the influence of both alcohol and THC, the main psychoactive component in cannabis.
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While there are some roadside tests that police can administer to drivers suspected of being under the influence of marijuana, there's no chemical test that detects marijuana content in the blood like there is for alcohol.
A file image shows a man smoking a joint during a march demanding the legalization of marijuana in Sao Paulo, Brazil, on June 1, 2019. (Photo credit: MIGUEL SCHINCARIOL/AFP via Getty Images)
Jack Nissen is a reporter at FOX 2 Detroit. You can contact him at (248) 552-5269 or at Jack.Nissen@Foxtv.com