• Posted October 6, 2025

Two Of Five Drivers Killed In Car Crashes Were Stoned, Study Says

More than 2 in 5 drivers were driving while stoned when they died in car wrecks in a major Ohio county, a new study says.

Coroner records show that nearly 42% of drivers who died in motor vehicle collisions during a six-year period tested positive for THC, researchers are to report Tuesday at a meeting of the American College of Surgeons in Chicago.

The deceased drivers had an average THC level of 30.7 ng/mL — far above the 2 ng/mL to 5 ng/mL legal limit set by other states, researchers said. THC is the chemical in weed that produces intoxication.

“I was surprised to see that level,” lead researcher Dr. Akpofure Ekeh, a professor of surgery at Wright State University in Dayton, Ohio, said in a news release.

“An average level of 30.7 ng/mL generally means those people must have consumed marijuana at some time close to driving,” Ekeh said. “This isn’t about residual use; it’s about recent consumption.”

For the study, researchers analyzed death records from Montgomery County, Ohio, where Dayton is located. Medical cannabis was approved in Ohio in 2016, and recreational use in 2023.

The team focused on 246 drivers between January 2019 and September 2024 who were tested for THC following their fatal crash.

Of those drivers, 103 tested positive for THC. These blood tests are typically drawn within hours of death, providing an accurate snapshot of a driver’s state of impairment at the time of the crash, researchers said.

However, the 2023 legalization of recreational marijuana did not appear to change the rate of people killed driving while stoned, researchers found.

The rate of deceased drivers who tested positive for THC did not change significantly before or after legalization – 42% on average versus 45%.

“The messaging over the last few years has been just the push towards recreational legalization,” Ekeh said.

“The problem is that from a public health standpoint, there has not been enough emphasis on some of the downsides and the dangers that can occur,” Ekeh continued. “People should treat smoking marijuana just like they treat alcohol: don’t smoke and drive.”

More information

The U.S. Centers for Disease Control and Prevention has more on cannabis and driving.

SOURCE: American College of Surgeons, news release, Oct. 23, 2025