What You Need to Know About Marijuana DUIs in Washington

What You Need to Know About Marijuana DUIs in Washington

Marijuana joint Creative Commons Photo by Torben Bjorn HansenIn December 2012, Washington legalized the recreational use of marijuana with Initiative 502. If you are at least 21 years old, you can possess up to one ounce of marijuana in Washington. But, as Tom Waits once said, “[t]he large print giveth and the small print taketh away.” Sure, I-502 made some acts legal, but it criminalized others: I-502 created a new way to get marijuana DUIs in Washington State.

Knowing how I-502 changed the landscape of DUI laws may keep you out of handcuffs. These types of DUIs are not rare: marijuana is the second most frequently detected drug among drivers, after alcohol.

Before I-502, to get a DUI after consuming marijuana, the prosecutor would need to prove the driver was under the influence of marijuana to the point that it affected the person’s driving under what is known as the “affected by” prong of the DUI statute. After I-502, the prosecutor needs to prove the driver had 5.00 nanograms per milliliter of whole blood or higher of THC (“5 ng/mL”) under what is known as the “per se” prong. The key difference: a conviction under the affected by prong requires evidence of possible impairment (i.e., bad driving, appearance of having consumed marijuana, poor performance on roadside tests, etc.), but a conviction under the per se prong requires no outward indicators of impairment (apparent/actual sobriety). Often, drivers accused of DUI will believe that they were totally okay to drive, yet still test above 5 ng/mL.

How Impaired is Impaired?

The short answer is you may not be impaired at 5 ng/mL of THC in your blood. In other words, you might look and feel “sober” at or above the 5 ng/mL per se marijuana limit.

People’s response to drugs and tolerance vary significantly. And, a person’s tolerance can increase with use. Take a frequent or medical user: such a person may have THC in his or her system for days after abstaining from marijuana.

Because of these variables, any one value of blood-THC content may not translate to a predictable level of impairment in some people. Compare this to alcohol, where blood-alcohol does translate to predictable levels of impairment. Since blood-alcohol correlates predictably to levels of impairment, a per se law is reasonable for alcohol DUI.

Not so with THC.

Even if everyone if blood-THC was a predictable indicator of impairment from person to person, there is no consensus as to what blood-THC content is impaired. Among these studies, few studies evaluate driving performance on drugs. Problematically, the studies that are available are usually based on laboratory performance or closed-track studies, the findings of which may not apply to actual driving situations.

How do I know I am okay to drive?

In a DUI trial, the prosecution will often call an expert on the symptoms, effects, and detection of alcohol and drugs in the human body, called a toxicologist. I have heard the state toxicologist testify that a person’s blood THC concentration will fall to less than 5 ng/mL within 2-3 hours of smoking marijuana.

This testimony is deeply flawed because it suggests that related variables have no effect on the body’s elimination of THC in its system. What if the marijuana smoked is exceptionally strong (medical grade)? What effect does a person’s physiology have? What if the person is a chronic/medical user?

What’s more, the toxicologist doesn’t know the answers to these questions. (Because of this, seeing how many “I don’t knows” you can get out of the toxicologist is generally a good tactic for cross examination.)

Whether 2-3 hours is an appropriate guideline is specific to the individual. My default advice is to get a ride. Of course, if you are medical user, there may never be a time when you can lawfully drive under the per se statute.

 Crazy Drivers / Road Lightning Creative Commons Photo by Rhys AsplundhTo avoid marijuana DUI in Washington, first and foremost, understand your limit and be safe. If you are being safe, three ways you can avoid a false accusation of DUI:

1. Obey traffic laws and go the speed limit. If you aren’t stopped, an officer can’t investigate. Many people commit traffic infractions out of habit; remember to signal, don’t change lanes in an intersection, stay in the right lane, etc.

2. Don’t smoke marijuana or store marijuana in your car. Smell is almost always the first thing an officer notices before a traffic stop turns to a DUI investigation. Have your legal ounce of marijuana? Put it in the trunk.

3. Exercise your right to privacy. Just because marijuana is legal, doesn’t mean you need to brag to the officer about it. If you are asked if you smoked recently, exercise your state constitutional right, and say, “I’m not gonna go there…”

Do you have a specific concern about driving and marijuana? Give me a call at (253) 906-0393 and we can talk about some more ways to drive lawfully.

Photo Credits: Torben Hansen, Rhys Asplundh


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