Marijuana and Driving: 2014 Update

As Washington’s first wave of pot shops opened in early July, it is high time for a quick recap of our state’s laws prohibiting stoned driving. It has been over a year since Bill Kirk’s excellent post on the myths and facts of Washington marijuana law, and DUI laws have since changed.

It is a crime to drive a motor vehicle while under the influence of marijuana. There are two ways that a prosecutor may prosecute driving under the influence of marijuana.

The “Affected By” Prong

First, he or she may prosecute under the “affected by” prong. This means that the prosecutor will have to prove that the driver was under the influence of, or affected by, marijuana when he/she drove a motor vehicle. This is usually done by introducing testimony from an officer who will state that the driver smelled of marijuana, behaved in a manner consistent with marijuana intoxication, and otherwise exhibited symptoms of being under the influence of marijuana. The most useful evidence the prosecutor may have is the result of a “drug recognition exam” (DRE). This exam is similar to the standardized field sobriety tests, but is much more involved, and requires an officer who has been trained and certified in the administration of DREs.

The Per Se Prong

Second, the prosecutor may introduce evidence that the driver had 5.00 or more nanograms per milliliter of whole blood of active THC in his or her system within two hours of driving a motor vehicle. This is a per se equivalent to the .08 alcohol limit. The only way to obtain this evidence is with a blood test. Drivers who are under 21 and have a THC concentration of below 5.00 but above 0.00 may be charged with minor DUI.

Drivers May Refuse a Blood Test

Needless to say, proving marijuana DUI under the per se prong is much easier than the “affected by” prong. However, the most drastic change to DUI laws last year is the removal of blood testing from the state’s Implied Consent Warning statutory scheme. The state may no longer suspend the license of a driver who refuses to take a blood test. Thus, the Legislature removed the prosecution’s principal vehicle for obtaining marijuana DUI convictions.

In its place, police are now asking for “voluntary” submissions of blood samples from arrestees. Refusing to provide a voluntary blood sample has no negative consequences. In order to secure a blood sample, police must now apply for a search warrant. Fortunately, getting a search warrant really is not difficult at any time of day, as most counties have on-call judges specifically for that purpose.