Global Ganja Report

Questions about road safety have been a real concern as cannabis legalization has unfolded across 11 states, with medical marijuana laws in many more. But with several years of data to analyze, a new study finds no link between these policies and traffic fatalities.

The annual carnage on America's highways is a grim reality that has caused some to question the wisdom of cannabis legalization. However, the notion of a link between road fatalities and lifting the legal pressure on cannabis doesn't stand up to the number-crunching.

The latest to reach this conclusion is a new study published in the journal Traffic Injury Prevention, looking particularly at pedestrian fatalities. Carried out by a team from the University of Minnesota School of Public Health, it found that enactment of state-level policies legalizing for either medical or general adult use has not been associated with an increase in the prevalence of fatal motor-vehicle crashes involving pedestrians.

According to a summary on the website of NORML, the national legalization advocacy group, investigators examined the association between loosening of cannabis laws and fatal crash rates (both pedestrian-involved and total fatal crashes) during the years 1991 to 2018—a period spanning the first moves toward medical marijuana laws and the embrace of general cannabis legalization by the three states the study focused on. Motor-vehicle accident trends in Colorado, Oregon, and Washington were compared to trends in five control states.

Relying on data from the Fatality Analysis Reporting System (FARS), maintained by the federal Transportation Department's National Highway Traffic Safety Administration (NHTSA), the researchers failed to identify any increase in pedestrian-involved fatal motor-vehicle accidents that could be attributable to enactment of more liberal cannabis laws. Indeed, they noted that two of the three states they examined, Washington and Oregon, actually saw decreases in fatal accidents following instatement of medical marijuana laws.

The study states: "While attention has been given to how legalization of recreational cannabis affects traffic crash rates, there was been limited research on how cannabis affects pedestrians involved in traffic crashes. This study examined the association between cannabis legalization (medical, recreational use, and recreational sales) and fatal motor vehicle crash rates (both pedestrian-involved and total fatal crashes)... We found no significant differences in pedestrian-involved fatal motor vehicle crashes between legalized cannabis states and control states following medical or recreational cannabis legalization. Washington and Oregon saw immediate decreases in all fatal crashes (-4.15 and -6.60) following medical cannabis legalization..."

The study did find: "Colorado showed an increase in trend for all fatal crashes after recreational cannabis legalization and the beginning of sales (0.15 and 0.18 monthly fatal crashes per 100,000 people)."

The authors concluded, "Overall findings do not suggest an elevated risk of total or pedestrian-involved fatal motor vehicle crashes associated with cannabis legalization."

A consistent finding
This is not the first time the scientific community has brought back such results from research on the question. As NORML states, "The study’s findings are consistent with those of others...reporting decreases in incidences of fatal motor vehicle accidents following the enactment of medical marijuana legalization."

And while NORML adds that "studies assessing the impact of adult-use retail sales on traffic safety have yielded more mixed results," the most recent of these have also dismissed a link between legalization and road fatalities.

For instance, one study last year by researches at Kansas State University found that cannabis legalization has not been linked to an increase in traffic deaths.

Also last year, a study by Canadian researchers on cannabis and driving cast doubt on zero-tolerance limits for THC. The study found that THC can indeed impair driving—but that applying laws designed for booze to cannabis is bad science and bad policy. THC, unlike alcohol, stays "in your system" (that is, detectable in your blood) long after its psychoactive effect has subsided—and also does not debilitate motor skills the way alcohol does. Instead, the authors of the Canadian study called for a "behavioral" test to see if a driver is impaired.

Economics versus cannabis as driving road carnage
The question of "marijuana-impaired driving" tends to be misunderstood. For example, it is true that Colorado has seen an increase in overall road fatalities since legalization in 2012, as well as an increase in cannabis-related driving offenses. But the increase in road fatalities is consistent with the trend across the US—and likely related to more motorists on the highways due to low oil prices. It was fortuitous for the prohibitionists that the world oil slump began in 2014—just in time to provide negative spin for cannabis legalization.

The Oregon Department of Transportation admits, "There was a dramatic increase in the number of fatalities, in line with the rest of the nation, in Oregon starting in October 2014," the year Oregon voted to legalize. But, as noted above, there was no such increase after Oregon (and Washington) legalized medical marijuana in 1998. 

Indeed, a 2011 study by the University of Colorado found a reduction in traffic fatalities in states that had legalized medical marijuana. A possible explanation is that folks began turning to more freely available cannabis instead of alcohol or meth—which impair driving far more dramatically.

A breakdown of the figures provided by the FARS shows that national traffic fatalities had been holding at between 40,000 and 42,000 from 1994 to 2008, the year of the economic crash. They then dropped below 40,000, reaching a low of 32,744 in 2014—the year oil prices began their plunge. After that, they started to rise again, reaching 36,560 in 2018, the last year for which the FARS chart provides figures.

Paradoxically, the total number of all deaths per week in the US actually dropped over the period this spring that economic activity ground to a halt under the COVID-19 lockdowns. This was due to reduced highway carnage—the same trend that we also saw during the last economic downturn in 2018, but which was dramatically reversed over the past years of low oil prices. 

Which brings us to the reality that the pandemic and attendant economic crisis may afford us the opportunity to rethink and redesign our modes of transportation. Because ultimately, it is automobiles that are responsible for the carnage on the nation's roads. A fundamental and obvious fact that tends to get lost in all the talk about THC (or even far more debilitating things, like alcohol) in the bloodstreams of motorists.

Cross-post to Cannabis Now

Image: Karin Dalziel via Flickr

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