The research, titled “Marijuana Legalization and Rates of Crashing Under the Influence of Tetrahydrocannabinol and Alcohol,” and published in The American Surgeon, was carried out by researchers in New Jersey at the Hackensack University Medical Center. The medical facility looked at patient data from states that had legal cannabis, as well as states that did not, and compared them over the period of 12 years. The study started in 2006 and concluded in 2018.
In order to determine these patterns, the study looked at the percentage of patients who tested positive for THC and compared it to the percentage of patients who drove under the influence of alcohol.
From the beginning, the aim of the study was to show whether or not cannabis incidents in car accidents were different in states with legal cannabis. In the words of the study, the goal was “to determine if statewide marijuana laws impact upon the detection of drugs and alcohol in victims of motor vehicle collisions.”
Overall, when the date was compared, the rate of cannabis apparent in crash patients did increase, but across the board—not just in legal states. Arizona, California, Ohio, Oregon, New Jersey, and Texas all experienced increases. Also of note, Texas, where cannabis is not legal, experienced the highest rate of increase, and California and Oregon both saw increases on the lower end.
“There did not appear to be a relationship between the legalization of marijuana and the likelihood of finding THC in patients admitted after MVC (motor vehicle crash).,”the study explained. “In fact, in Texas, where marijuana remains illegal, there was the largest change in detection of THC.”
Along with this assessment, the authors of the study also looked at changes in patients involved in motor vehicle accidents with alcohol in their systems. The goal was to look at how cannabis use and driving was impacted by cannabis legalization. Overall, the study found no significant change after cannabis became legal in some states.
The Conclusion and Other Studies
Regarding the study and the patterns noticed, “There did not appear to be a relationship between the legalization of marijuana and the likelihood of finding THC in patients admitted after MVC (a motor vehicle crash).” The researchers came to the conclusion that, “There was no apparent increase in the incidence of driving under the influence of marijuana after legalization. In addition, the changes in marijuana legislation did not appear to impact alcohol use.”
This was not the first study to look at the relationship between cannabis legalization and car accidents, or to try to determine if there is a relationship at all. Some of the studies carried out showed findings similar to this one, noting a minor increase in crashes since legalization, and others did not show a change at all.
Based on the results of this study, there is no clear connection between cannabis legalization and cannabis use in crash victims.