More Car Crashes in States with Marijuana Legalization

Home » More Car Crashes in States with Marijuana Legalization
June 21, 2021
Edward Smith

New IIHS Study Looks at Rising Crash Rates

A new study shows that car crash rates rise when states pass laws that legalize the recreational use of marijuana. The following states saw an increase in the number of crashes following the legalization of retail sales and recreational use of marijuana:

  • Oregon
  • California
  • Nevada
  • Colorado
  • Washington

These results are from a recent Insurance Institute for Highway Safety (IIHS) study. The conclusions were supported by a separate study done by the Highway Loss Data Institute (HLDI), an agency affiliated with IIHS.

Contrasting Evidence Exists

The IIHS has also conducted a different study, of which the preliminary results suggest that drivers who use only marijuana were not any more likely to be involved in a car crash than drivers who had not used the drug. This study was based on visits to emergency rooms in Colorado, California, and Oregon. A 2015 study done by the National Highway Traffic Safety Administration (NHTSA) also found that a positive marijuana test was not associated with a higher risk of being in a police-reported auto accident.

Considerations of the Newest Study

The President of IIHS-HLDI states that the newest research clearly shows that the legalization of recreational use of marijuana does cause an increase in crash rates. He suggests that this will need to be addressed by safety professionals and policymakers as additional states move toward legalization. This is despite the uncertainty of whether marijuana use affects the crash risk for drivers on an individual basis.

Driving Simulation Tests

Interestingly, driving simulation tests have revealed that drivers high on marijuana have a tendency to have reduced attention, react more slowly, and have difficulty staying in their correct lane position. They also have been shown to make more mistakes when things go wrong versus when they are unimpaired. However, the same tests show that drivers who have used marijuana are more likely to drive slower, keep a greater distance between their vehicles and others, and make fewer attempts at overtaking other vehicles. These factors seem to offset the negative effects, which may help to explain the prior studies’ findings. 

Other Factors to Consider 

One reason crashes may have increased despite inconsistent studies is that people are using legalized marijuana in conjunction with other substances, such as alcohol. The latest research done by the IIHS showed that the use of marijuana alone did not increase the crash risk, but the risk rose when marijuana use was combined with the consumption of alcohol. The combined-use findings may help explain why crash rates have risen. The legalization of the recreational use of marijuana may have led to more people drinking and using marijuana together.

Colorado was the first state to legalize recreational marijuana use. That state experienced a car crash spike shortly thereafter, which may have signified a burst of enthusiasm for using, which has since worn off. There may have also been people from other areas traveling to Colorado to buy marijuana, which could account for some of the crash increase as well.

Given the conflicting studies and multiple factors, the net impact on traffic safety resulting from the legalization of recreational marijuana use requires further study. 

Watch the YouTube video. Below is a TEDx talk on the complicated issue of marijuana’s effect on driving.

Sacramento Personal Injury Lawyer

Welcome – and thank you for reading our discussion of the potential effects that marijuana legalization has on car crash rates. I’m Ed Smith, a personal injury attorney in Sacramento, California. For more than 38 years, the injury lawyers at my firm have advocated for injured area residents. If you have suffered injuries due to the negligence of an impaired or reckless driver, call us for experienced legal counsel. One of our skilled injury lawyers would be happy to dispense free and friendly advice. Our local number is (916) 921-6400 and our toll-free line for Northern Californians outside of the Sacramento region is (800) 404-5400. 

Photo: https://pixabay.com/photos/seedling-cannabis-marijuana-1062908/

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