Rules of the Road

No, smoking pot will not sober you up after drinking – but some drivers think it will

Here are some of the myths about driving while high

Vivian McPeak, the director of HempFest, and Darrin Grondel, the director of the Washington Traffic Safety Commission, sat down to talk about some cannabis myths and the risks of driving high.
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Vivian McPeak, the director of HempFest, and Darrin Grondel, the director of the Washington Traffic Safety Commission, sat down to talk about some cannabis myths and the risks of driving high.

What kind of behavior do you visualize when you hear the terms “impaired driving” or “DUI?” If your mind translated the word “impaired” to the word “drunk” or “DUI” turned into “driving under the influence of alcohol” that would be understandable, but no longer entirely accurate.

Impaired driving is changing, or more accurately, has already changed in Washington.

Impaired driving is the leading contributing factor in Washington fatal crashes, and has been for many years, but the dominant form of impairment is no longer just alcohol.

Of the 565 traffic fatalities in Washington in 2017, 266 involved an impaired driver. Of those 266 drivers, 181 of them had been drinking alcohol and 200 of them were impaired by drugs. That adds up to a lot more than 266, and that overlap is where we encounter poly-drug impairment; using two or more impairing substances at the same time.

You can probably guess the most frequently combined substances: alcohol and cannabis. By 2016 poly-drug drivers involved in fatal crashes were more than twice the number of alcohol-only drivers and more than five times the number of cannabis-only drivers.

There is reason to be concerned. From 2007 to 2014 drivers testing positive for cannabis increased by 50 percent. We still have a segment of our population that isn’t convinced that cannabis impairs their driving, despite multiple studies confirming that driving under the influence of cannabis increases crash risk. That seems obvious to me, even without a study.

Sometimes drivers use cannabis in an attempt to counteract the effects of alcohol. In a recent survey, 77 percent of people who drive under the influence of cannabis and alcohol (DUICA) stated that they are likely to feel anxious after drinking alcohol and use cannabis to calm down, and 52 percent said they are likely to feel too impaired after drinking and then use cannabis to sober up.

Just to be clear, cannabis does not reduce alcohol impairment. It may alter the feeling of impairment, but combining alcohol and cannabis makes us more impaired, not less impaired.

Do I have you concerned about the kinds of people driving on our roads? That concern is well-founded, but allow me to offer some hope. Despite the increases in poly-drug driving, most Washingtonians (81 percent) have a negative attitude about DUICA. And an even higher percentage of drivers (91 percent) don’t ever do it.

When a dangerous behavior, like DUICA, has such a negative impact on our community, it’s common to overestimate how often it happens or how many people are doing it. It turns out that only a small percentage of our population engages in the behavior.

That in itself is a good thing, but it also means those of us who are concerned are in a good position to do something about it.

We can start by influencing cultural attitudes about poly-drug use and driving. If you find yourself in a conversation with someone who has misperceptions about the risk of DUICA, take an opportunity to share with them what you know: that DUICA is not safe, most people believe it is unacceptable, most people don’t do it, and using cannabis after drinking does not make it safer to drive.

With more than four out of five Washingtonians concerned about DUICA, If you’re in a group conversation there’s a high likelihood that others in the group will back you up.

We’re in the midst of holiday celebrations right now, so there’s a pretty good chance that some of us will encounter someone who not only has misperceptions about DUICA, but is also impaired and intends to drive. If you’re in that circumstance it might be reassuring to know that when Washingtonians are in a situation to intervene, most (81 percent) take steps to prevent someone from driving impaired.

If you try to intervene but the person insists on driving impaired, don’t hesitate to call 911 and report the driver. That might be hard if it’s someone you know, but considering the terribly outsized impact that impaired driving has on traffic fatalities, you could be saving someone’s life. To back you up, law enforcement agencies are conducting extra DUI patrols through the holidays.

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Doug Dahl, Target Zero Manager for the Whatcom County Traffic Safety Task Force, answers questions about road laws, safe driving habits and general police practices every Monday. Ask him a question using our form. Target Zero is Washington’s vision to reduce traffic fatalities and serious injuries to zero by 2030. For more traffic safety information visit