Last updated : November 11, 2024
Thanks to cultural changes in the United States, the number of deaths caused by drunk drivers has plunged in the past few decades. A different cultural change could cause the number of car traffic fatalities to soar in the future, however, and that is the acceptance of marijuana as a legal drug.
In November, 2012, Colorado and Washington became the first two states in the United States since the 1930s to permit their residents to possess and sell marijuana for recreational use. The referendums in these two states spurred successful pro-recreational marijuana referendums in Alaska, Oregon, and Washington, D.C., in 2014 and in California, Maine, Massachusetts, and Nevada in 2016. In addition, medical marijuana is now legal in 31 states.
Will the acceptance and growing use of marijuana negate, at least in part, the dramatic improvement in public safety that has occurred since driving while impaired with alcohol has become less accepted in the American culture and lawmakers have reacted to that change by passing far more stringent anti-drunk driving laws? According to Mothers Against Drunk Driving, the number of Americans killed in drunk driving auto accidents plunged from 1980 to 2014. There were more than 25,000 deaths in 1980 and fewer than 10,000 in 2014.
It’s far too early to say definitively, but the early studies of the effect of the more permissive attitude toward marijuana are certainly not promising. The early studies have focused on Colorado and Washington because they’re the first two states to legalize marijuana for non-medicinal purposes—a change that results in far more people using marijuana than medical marijuana laws. The findings of the studies include:
- The number of “marijuana-related traffic deaths in Colorado increased from 71 in 2013 to 94 in 2014, an increase of more than 32 percent, reported a federally-supported task force called the Rocky Mountain High Intensity Drug Trafficking Area (RMHIDTA) Investigative Support Center. In its report, which was entitled “The Legalization Of Marijuana In Colorado: The Impact,” RMHIDTA notes that retail marijuana businesses became legal in 2014, not 2013.
- The percentage of car traffic fatalities in Colorado that were marijuana-related began increasing substantially in 2009, the first year that medical marijuana was commercialized, reports RMHIDTA. The percentage figure rose from 7.85 percent in 2008 to 10.1 percent in 2009 and was 19.26 percent in 2014, the last year covered by the 2015 report.
- The number of hospitalizations in Colorado related to marijuana use increased 38 percent from 2013 to 2014, while the number of marijuana-related visits to hospital emergency rooms increased 29 percent during the same time. This indicates that more Coloradans have marijuana abuse problems because the drug is now legal.
- The number of marijuana-related deaths in the state of Washington began soaring nine months after the drug became legal for recreational use in late, 2012, reported the AAA Foundation for Traffic Safety in a report entitled “Prevalence of Marijuana Involvement in Fatal Crashes: Washington 2010-2014.” The number of drivers in fatal crashes who had Tetrahydrocannabinol (THC), the primary psychoactive chemical in marijuana, increased from 49 in 2013 to 106 in 2014.
- The percentage of drivers in fatal auto accidents in Washington who had THC in their blood increased from 8.3 percent in 2013 to 17 percent in 2014. From 2010 to 2013, the percentage was between 7.9 percent and 8.5 percent so the jump in 2014 was dramatic.
- Drivers who were arrested in Washington for driving under the influence and had only THC in their system performed far worse than “drug-free control” subjects in tests such as the finger-to-nose tests, the one-leg stand, and the walk-and-turn that measured whether they were impaired physically and mentally by marijuana, according to this AAA report. They were also more likely to have eyelid tremor and eyes that were bloodshot, red, and watery.
The AAA Foundation for Traffic Safety is concerned that the other states that recently legalized marijuana for recreational use have experienced similar jumps in auto traffic deaths although there are no published studies on those states yet.
Washington was one of the first two states to legalize the recreational use of marijuana, and these findings serve as an eye-opening case study for what other states may experience with road safety after legalizing the drug,” the AAA Foundation said in a press release entitled “Impaired Driving And Cannabis.
This is especially concerning considering the prevalence of drug use already within Denver’s transportation industry.
Measuring THC’s impact is difficult
The concern among the law enforcement community and safety regulators such as the Department of Transportation and the National Highway Traffic Safety Administration, are that marijuana-related traffic fatalities will soar if the drug becomes legal in more states is justified if an increase in marijuana use by drivers has already occurred regardless of whether it is legal.
In fact, the percentage of driving deaths in which marijuana was a contributing factor tripled from 4 percent to 12 percent from 2000 to 2010, according to a study by Columbia (N.Y.) University researchers, cited in a USA Today article. It reported that drugged driving was a particular problem among young drivers because about one out of every eight high school seniors has driven after smoking marijuana and almost half of the marijuana-related fatalities were younger than 25.
Unfortunately, there is a major problem in the fight against drugged driving that does not exist in the fight against drunk driving—THC doesn’t measure how people are impaired by marijuana in the same way that blood alcohol measures how people are impaired by liquor. Colorado and Washington have laws stating someone who has five nanograms of THC per milliliter of their blood is driving under the influence of marijuana, but it’s not an absolute indicator of impairment.
“While tests show the ability to drive gets worse as blood alcohol rises, laboratory studies show the same is not necessarily true with increased levels of THC, the main chemical component in marijuana, in the blood,” reports CNNMoney in an article entitled “Fatal accidents involving stoned drivers soared in Washington since pot was legalized.” “One driver with high levels of THC might not be impaired, while another driver with very low levels can be impaired.”
Martha Bebinger, a health-care reporter for WBUR, a Boston radio station, explains in an article she wrote entitled “No Widely Accepted Way To Test Marijuana Impairment In Drivers” that marijuana is stored in body fat so it can be found in a user’s blood, saliva or urine weeks after it no longer has an effect.
“Proponents of the legal marijuana law in Massachusetts say the best thing the Legislature could do to curb impaired driving would be to require that police videotape the entire encounter — from the alleged erratic driving through the field sobriety test,” wrote Bebinger.
Because it is impossible to quantitatively ascertain current impairment, the only rational answer at this point in time is to enforce a zero tolerance policy towards drivers. If a driver is found to have any traces of THC in their system, their licence should be revoked for a minimum of one year. This is absolutely necessary to help protect the safety of other citizens on our roadways.
