Jul 30

Harlan Law Staff


by Harlan Law Staff

For most people, driving drunk is the only way they think about DUIs.  However, especially with the recent legalization of marijuana in Washington, drug DUIs are becoming increasingly more common.  A person can be DUI if their driving is affected by alcohol, drugs, or some combination of the two.  For marijuana, a person can be under the influence, or have their blood show that they’re over the legal limit for THC in the system.  It can be a complicated area where a person might be committing the offense and not even know it.  Being lawfully able to use the drug, even if prescribed, is not a defense to driving under the influence of drugs.

First, since marijuana DUIs are most similar to alcohol-related DUIs, they are probably the easiest to understand.  It is not unlawful to consume marijuana and drive, but it is unlawful to have your driving affected to any appreciable degree by the drug, or to be over the legal limit.  In Washington, for people who are over 21 years old, the legal limit is 5 nanograms of THC.  For under 21 drivers, the limit is 0 nanograms.  The question of whether a person’s ability to drive is affected is a question of fact, and the answer will look similar to alcohol DUI.  It is commonly referred to as an “affected-by” case.  Either way, there can be a lot of uncertainty in both prosecuting and defending these types of cases. 

As to the legal limit, the science behind marijuana can help shed some light.  As a quick aside, the Department of Licensing will only take an action separate from the criminal process in alcohol and marijuana cases when there is evidence the driver was over the legal limit; otherwise, there will be no DOL action, and the only licensing consequences come from the criminal action.  Unlike alcohol, there is not a body data as to the rate of uptake nor the rate of dissipation for marijuana.  Still, some information is known about the way it moves through the body. 

There are two forms of THC: hydroxy and carboxy.  Hydroxy is the psychoactive component that creates the sensation of being high; it dissipates relatively quickly. Carboxy is the metabolite that causes no psychoactive effects; it remains in the system for much longer than the hydroxyl.  The DUI statute does not differentiate between the two, but it is difficult to imagine a scenario where the prosecutor would proceed on a marijuana DUI without any psychoactive component.  In short, a marijuana DUI based on being over the legal limit should need some evidence that there are more than 5 nanograms of hydroxy-THC in your system. 

Even so, it is unclear how the legislature arrived at its decision to say that more than 5 nanograms is legal impairment.  Anecdotally, the relevant data suggests that impairment is highly dependent upon use and tolerance.  There are some people who would appear impaired at less than 5 nanograms, and some who would show no signs of impairment when they were 3-4 times the legal limit. 

Proving an affected by case, either for marijuana, drugs, or a combination of alcohol and drugs, requires at least some affirmative evidence (i.e. a blood test) that the driver had drugs in his or her system, and that the drugs affected the driving.  Aside from alcohol and marijuana, there is no legal limit for any other drugs in Washington.  It is important to note that the Standardized Field Sobriety Tests have not been validated to show drug-related impairment.  Some officers will try and convince a prosecutor, judge, and jury that they do, but there is no research to back this up. 

On the other hand, there are some officers who have some amount of specialized training in drug recognition.  They are called Drug Recognition Experts (DRE) and perform Drug Recognition Exams.  Only those officers who have been through the training may conduct the exams.  They will use the field sobriety tests as part of an exam, but will go into more detail, attempting to classify the drug and determine the level of affectation on a person.  Depending on the person’s driving performance, performance on any sobriety tests administered, and both the category and level of drug in the system, the case may or may not be defensible.  Unfortunately, just as these cases can be easier to defend because of their uncertainty, they can also be easier to prosecute.  It is highly dependent upon the specific facts of the case. 

If you find yourself charged with DUI, the attorneys at Harlan Law Firm offer a free consultation to discuss the various aspects of your case.  We will educate you and can stand by your side.  Remember this blog is just a guide, it is not a complete and exhaustive resource, and each case is different.