The number of drivers with alcohol in their system has has gone down significantly while the number of drivers using marijuana has gone way up. Safety-wise this doesn’t seem to be a bad trade. A recent National Highway Traffic Safety Administration (NHTSA) study (.pdf) has found that drivers with THC in their blood are no more likely to be involved in car crashes than are drug-free drivers.
In the largest survey of its kind ever conducted, NHTSA assessed whether marijuana use by drivers is associated with greater risk of crashes. Its findings were an interesting yes and no: marijuana-using drivers are more likely to be involved in car accidents, but that increased risk appears to be because marijuana users are more likely to be in groups at higher risk of crashes, i.e., marijuana users are more likely to be young men.
As Paul Armentano explains it in his blog post on the NORML website, the drivers who tested positive for any amount of THC have an unadjusted, elevated risk of having an accident of 25 percent (Odds Ratio=1.25) compared to drivers who tested negative for any drug or alcohol. But “this elevated risk became insignificant (OR=1.05) after investigators adjusted for demographic variables, such as the drivers’ age and gender.”
These results are vindication for marijuana rights advocates, as they contradict allegations that marijuana use increases car accident risks. Instead, Mr. Armentano says the results are “largely consistent with those of a 2013 literature review published in the journal Accident Analysis and Prevention which reported that cannabis-positive drivers did not possess a statistically significant risk of a either fatal accident or a motor vehicle accident causing injury.” The NHTSA made a similar acknowledgement in their report, stating that “the results of this study are consistent with previous well-controlled studies.”
The NHTSA study is likely to become fodder for the marijuana legalization political movements in California and other states.
For more on this issue, check out CEB’s CLE program Marijuana DUI: Does Cannabis Impair Driving?, available On Demand.
Other CEBblog™ posts you may find interesting:
- The Green Rush: Can City Regulations Keep Up?
- The Reek of Reefer Alone Does Not Justify Warrantless Search
- DUI Basics Every Attorney Should Know
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