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Cannabinoid Positivity in Traffic Fatalities Before and After Cannabinoid Legalization: A Retrospective Analysis in
Stacy K Thomas1, Michelle S Clark2, Amanda L A Mohr3
1Department of Pathology, Yale University School of Medicine, New Haven, CT.
Abstract:
Cannabinoid positivity in motor vehicle collision (MVC) fatalities is a topic of public interest, particularly as cannabis legalization expands. In Connecticut, recreational cannabis legalization in 2021 raised questions about impairment in fatal motor vehicle crashes. A retrospective study using Connecticut Office of the Chief Medical Examiner (CT OCME) data investigated MVC fatalities between 2018 and 2024, providing 3.5 years of data before and after legalization. We examined 1168 driver, 380 pedestrian, and 52 suicide fatalities. For the drivers, cannabinoid positivity increased from 32.8% prelegalization of cannabis to 37.9% postlegalization (P=0.0789). There was a statistically significant increase in cannabinoid-positive motorcyclist deaths following legalization. For pedestrians, cannabinoid positivity increased from 11% prelegalization to 20.6% postlegalization (P=0.016). Multidrug detection was common in cannabinoid-positive cases, most frequently with ethanol. This study demonstrates a rise in cannabinoid positivity in driver and pedestrian MVC fatalities in Connecticut after cannabis legalization. The findings suggest cannabis may play a growing role in MVC fatalities, and/or a demonstration of greater cannabinoid use following legalization. The challenges with interpreting cannabinoid concentrations and the multidrug findings complicate the ability to attribute cannabinoid use to impairment. These data, however, are useful for understanding and responding to evolving drug trends in traffic fatalities.
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