WASHINGTON — An alarming number of people think they drive better after smoking pot, but the numbers say otherwise. Since recreational marijuana was legalized in 2012, a growing number of Washington drivers have been combining pot and alcohol with “deadly consequences,” according to a new state report.
The Washington State Traffic Safety Commission released “Marijuana Use, Alcohol Use and Driving in Washington State: Emerging Issues With Poly-drug Use on Washington Roadways” in April. The study used data from several surveys and other research projects to evaluate the safety-threat posed by people who drive under the influence of two or more substances.
Researchers found that these “poly-drug drivers” — most of whom use a combination of pot and booze — are killing people. According to the report, “Since 2012, the number of poly-drug users involved in fatal crashes has increased an average of 15 percent every year.”
There isn’t a lot of credible, current research about how marijuana affects drivers, because scientists and policymakers can’t keep up with the rapid expansion of the legal cannabis industry. Some widely-cited older studies found that cannabis had little to no effect on drivers. However, these studies aren’t credible because they included a large number of people who only tested positive for a marijuana compound that does not cause intoxication.
Scientists do know that it seems to amplify alcohol’s impact on a driver’s reflexes, coordination and judgement. The Washington study found fatal crashes involving poly-drug users started to spike around the time retail pot shops began doing business in 2014. These drivers appear to cause more damage than people who use marijuana or alcohol alone — by 2016, the number of poly-drug drivers involved in fatal crashes was more than double the number of alcohol-only drivers, and five times the number of pot-only drivers.
When Washington officials set about deciding how to set up a legal pot industry, they gave a lot of thought to ensuring ethical production and sales practices, keeping it away from kids and preventing drug-use in public spaces. They gave less thought to how the state might cope with a new onslaught of stoned drivers. Six years later, trends and patterns are emerging, and they’re not good.
Researchers used a variety of surveys to gather information about pot-related habits and attitudes in Washington. They learned that nearly one in five daytime-drivers may be under the influence of pot, up from less than one in ten drivers prior to the start of retail marijuana sales. Additionally, more than half of drivers between 15 and 20 think marijuana use makes their driving better. People who drove within three hours of using pot reported being more likely to drive after drinking, and less likely to use their seatbelts.
These risky behaviors have contributed to the state’s highest-ever numbers of poly-substance-involved deadly wrecks in recent years. According to the study, 90 percent of drivers in fatal crashes get blood-tested. Of these, 44 percent tested positive for two or more substances — mostly alcohol and pot — between 2008 and 2016.
State law sets a legal limit for driving under the influence of pot, but it’s hard to enforce. Police have tools for assessing drunk drivers in real-time, including field sobriety tests and breathalyzer tests, but these tools don’t work on pot-users. The only way to confirm marijuana intoxication is a blood test, so days or even weeks can pass before the officer has any proof that the driver was high. Without a scientifically-approved way to back up their observations, it’s harder for police to prove marijuana DUI cases.
Furthermore, many people in law enforcement suspect that, when combined, substances can act in unique ways, even when the user consumed only small amounts of each, but again, there isn’t enough research to back up their observations.
The unpredictable effects of combining substances may have been a factor in a July 3, 2016 collision near Black Lake that killed two local women. An autopsy later revealed that the causing driver, a 58-year-old Long Beach woman, had marijuana, alcohol, an antidepressant and two antihistamines in her blood. She was under the legal limit for both marijuana and alcohol, but investigators pointed out that alcohol can cause negative side-effects, including drowsiness, impaired thinking and slowed reaction times when combined with the two of the medications she was taking. The authors of the report concluded that more research is urgently needed to determine whether the same is true of marijuana and alcohol, but noted that “the consequences of combining these two impairing substances and driving are already apparent in Washington fatal crash data.”
There have been few other fatality crashes in the county in recent years, Washington State Patrol Sgt. Bradford Moon said on Sept. 10, but people in law enforcement believe they started seeing an uptick in less serious marijuana-related incidents soon after pot stores started doing business. He doesn’t expect that trend to change anytime soon.
“We do see a lot more marijuana-involved-with-alcohol,” Moon said.