Society once vilified marijuana. Later generations of hipsters laughed off the stigma. 

Now, mounting evidence has brought things full circle — vindicating the psychoactive drug’s original critics after all. 

Today’s high-potency pot — legalized for recreational use in Colorado in 2012 and in over two dozen other states since then — is leaving a trail of destruction. Whether it’s marijuana’s devastating impact on the mental health of our youth, or on the safety of our highways, it’s drawing overdue scrutiny that is justified by hard data.

Pot’s toll in traffic fatalities in particular is back in the news. A new study by Wright State University in Dayton, Ohio, looked at driver autopsy results from car crashes in surrounding Montgomery County, Ohio, from 2019 to 2024. It turned out more than 40% of the drivers who had died in those accidents had elevated levels of pot’s THC in their blood.

The Wall Street Journal recounted the compelling findings in an editorial last week, observing, “Auto fatalities have increased over the last decade even as cars have become safer and alcohol consumption has fallen. Could marijuana be contributing to more reckless driving?”

“It’s a fair question,” the Journal’s editorial continued. “Nearly a quarter of 18- to 25-year-olds used marijuana in the last month, according to a federal survey. As did 15% of those 26 or older.”

Pot pioneer Colorado is of course no newcomer to marijuana’s role in traffic tragedy. The chief of the Colorado Department of Transportation’s highway safety office testified at a hearing in 2023 before the state’s Marijuana Enforcement Division that more drivers involved in fatal crashes were testing positive for THC. And half of all drivers who tested positive showed levels above 5 nanograms per milliliter, the state standard for THC intoxication. 

An analyst with Colorado’s Department of Public Safety said at the same hearing that overall detection rates for THC went from 18% in 2016 to 29% in 2022. The department has also seen a gradual rise over the same time period for drivers who test positive for THC at the 5 mg/ml level.

About one out of every three drivers convicted of a DUI in 2020 was involved in a crash, department data shows. And those crash rates increased for drivers who tested positive for both alcohol and THC, to about 36%. For those who tested positive for alcohol, THC and another drug, it increased to 39%. 

Indeed, an extensive analysis of 26,000 impaired-driving cases in Colorado in 2019 showed 45% of drivers tested positive for more than one substance, according to the state’s Division of Criminal Justice. The most common combination was alcohol with THC — the psychoactive chemical in marijuana — followed by alcohol combined with other drugs, the analysis found.

Last week’s Wall Street Journal editorial also aptly noted that the Ohio study, presented recently at an American College of Surgeons conference, “ought to prompt the Trump Administration to slam the brakes on a mooted plan to move marijuana to a less risky level on the federal drug schedule. Such a move would cultivate the spurious belief that marijuana isn’t all that harmful despite reams of evidence to the contrary.”

Agreed. State policies liberalizing pot use evidently have done plenty to unleash carnage on our highways — without the feds giving it a green light, as well.