Marijuana DUI Law in Oregon and Your Rights

Marijuana DUI laws can be confusing. Oregon legalized the recreational use of cannabis (aka marijuana) in 2015, but that doesn’t mean that Driving Under The Influence of Marijuana is legal.


Oregon DUI Laws Criminalize Driving Under the Influence of Marijuana

DUI can be proven four different ways in Oregon:

  1. Driving on public highways or premises open to the public with a blood-alcohol level of .08 or greater,
  2. Driving on public highways or premises open to the public while adversely affected to a noticeable or perceptible degree by the use of intoxicating liquor,
  3. Driving on public highways or premises open to the public while adversely affected to a noticeable or perceptible degree by the use of controlled substances,
  4. Driving on public highways or premises open to the public while adversely affected to a noticeable or perceptible degree by the use of intoxicating liquor and controlled substances.

To put it more directly: It’s unlawful in Oregon to drive while drunk, buzzed, high, or high & buzzed. The slightest noticeable impairment by marijuana or cannabis is illegal.

Cannabis and Cars: The New War on Drugs

Before going into detail about Driving Under the Influence of Marijuana in Oregon or “DUII”, it’s important to understand that much of what law enforcement believes and reports about marijuana use is flat-out dishonest or– at best– misleading. The National Traffic Highway Safety Administration (NHTSA) intends to frighten the public about DUI and marijuana. NORML provides scientific research that suggests the problem of marijuana DUI is overstated or exaggerated. This is no surprise. Consider that many law enforcement officials have spent their entire professional lives demonizing marijuana for personal and professional gain– often using scare tactics and fear mongering– in order to push for greater funding of their departments and for public tolerance of the aggressive seizure/confiscation of money and personal property from people arrested for marijuana possession. Now that recreational marijuana is legal in Oregon, police agencies will be facing millions of dollars in losses. These departments used to have funding for dedicated helicopters, planes, armored personnel carriers (APCs), trucks, all-terrain vehicles (ATVs), automatic weapons, dogs (aka “K-9 units”), and other tactical gear to waste on the failed marijuana “drug war.” In order to attempt to regain some of their funding, they will now attempt to argue that Driving Under the Influence of Marijuana in Oregon is the latest and greatest threat to the safety of Oregonians. It never was. It isn’t. It will never be. But that will be their argument. In reading the information below, please keep in mind that cops use alchemy or voodoo “science” and therefore it’s important that you try not to focus on “right vs. wrong” or “evidence-based science vs. urban legend” because this article is intended to explain how cops approach DUI in Oregon and not whether their approach is scientifically valid, reasonable, fair, or even effective.


The Science of Marijuana DUI

Whether you enjoy recreational marijuana or use marijuana medicinally, if you use within weeks of driving, you are a target for law enforcement investigation, arrest, and charging of DUI. The reason for this is that– unlike alcohol– there is no set amount of tetrahydrocannabinol (THC)– the the principal psychoactive chemical substance in marijuana/cannabis– in the blood or urine of a driver which is presumed to cause mental or physical impairment. THC-COOH (the main secondary metabolite of THC which is formed in the body after cannabis is consumed) is typically measured in nanograms per milliliter (ng/ml), and detectable levels can remain in urine for weeks following marijuana use. While Oregon law presumes that a driver with a blood alcohol concentration (BAC) of .08 by weight is intoxicated or impaired by the use of alcohol, there is no such presumption if marijuana metabolites are present in small quantities or large quantities. The mere presence of marijuana metabolites over minimal threshold levels– combined with an officer’s suspicion of recent marijuana use– could be the basis for arrest and criminal charges.

Oregon uses Drug Recognition Experts or Drug Recognition Evaluators (DREs) to evaluate whether a given driver or test subject is under the influence of drugs. According to the Drug Symptom Matrix (or chart) relied upon by DREs, “general indicators” of marijuana/cannabis use include:

  • Very red eyes,
  • Odor of marijuana,
  • Body tremors,
  • Eyelid tremors,
  • Relaxed inhibitions,
  • Increased appetite,
  • Impaired perception of time and distance,
  • Possible paranoia, and
  • Disorientation.

The duration of effects will be assumed to be 2-3 hours.

If a DRE examination is requested by an officer– and if the driver participates in the examination– the evaluator would expect to see (or would say that they saw) some or all of the following indicators of cannabis use:

  • No Horizontal Gaze Nystagmus (HGN) (an involuntary jerking of the eye balls when tracking an object moving horizontally in front of the eyes),
  • No Vertical Gaze Nystagmus (VGN) (an involuntary jerking of the eye balls when tracking an object moving vertically in front of the eyes),
  • Lack of convergence (an inability to cross the eyes),
  • “Normal” pupil size or dilated (larger than normal) pupil size,
  • “Normal” reaction of the pupils to light (the pupils become larger in darkness, then quickly become smaller when exposed to light),
  • Elevated pulse rate (higher than normal pulse rate),
  • Elevated blood pressure (higher than normal blood pressure), and
  • Elevated body temperature (higher than normal body temperature).

Overdose signs will be assumed to be fatigue or paranoia.


False Arrests for Marijuana DUI

Here’s a real-world example of how a driver could be falsely accused and unlawfully arrested for driving under the influence of marijuana:

  • A driver is stopped for any number of possible moving violations or even for an equipment violation (such as a non-working license plate light or cracked windshield) under Oregon’s Vehicle Code.
  • The officer believes he smells the odor of either fresh or burnt marijuana coming from the driver or the vehicle.
  • The driver acknowledges that he smoked or ate marijuana hours prior, but is adamant that he is no longer feeling the effects of the drug.
  • The officer will likely not believe the driver, and will ask the driver to perform Standardized Field Sobriety Tests (SFTs).
  • If the driver declines (i.e. “refuses”) the tests– or performs them with any errors– the driver will be arrested, placed in handcuffs, and transported to a police station or the local jail.
  • Per Oregon law, the driver will then be asked to perform a breath test– even if the driver has not been drinking, and even if alcohol is not present in any form.
  • The driver’s breath test will likely come back as a .00 BAC if the driver has not consumed any alcohol.
  • The driver will then be asked to provide a urine sample and go through an additional evaluation by a Drug Recognition Evaluator (DRE). If the driver declines to provide a urine sample, the driver’s driving privileges will be suspended.
  • If the urine test comes back positive for any amount of marijuana metabolite and if the DRE forms the opinion that the driver was under the influence of marijuana, the case will be submitted to a local District Attorney’s office for criminal charges and further proceedings.
  • Whether the marijuana was used recreationally or medically (even pursuant to a doctor’s or nurse’s recommendation) will not legally matter for a DUI charge.
  • Whether or not the driver knew or should have known they were affected by the use of marijuana will not legally matter for a DUI charge.

How to Avoid a Marijuana DUI

While the narrative above may seem unreasonable and unfair, it’s an accurate example of how simple it is for law enforcement to accuse a driver of driving under the influence of marijuana. Short of never using recreational or medical marijuana, or short of never driving, marijuana users have limited options to protect their rights. Some suggestions to avoid a false charge of driving under the influence of marijuana would be:

  • Do not drive within several hours of using marijuana. For example, if using marijuana at night, do not plan on driving until the next day (after a full night’s sleep).
  • If driving within 3-4 hours of using marijuana, make sure the psychoactive effects of the drug have worn completely off, and that you are no longer feeling mentally or physically affected by the drug. Because the effects of marijuana can cause problems with perception, it would obviously be ideal to have a sober third-party not affected by the use of any alcohol or drugs provide an additional opinion as to whether or not you’re negatively affected by the drug before you drive.
  • Make sure your vehicle is in good working order, drive carefully, and do not get pulled over. This is common sense, but it’s especially important if you’re driving late at night (when drivers are more likely to be pulled over anyway for suspected DUI due to alcohol).
  • If an officer asks you any questions about marijuana possession or use, politely decline to answer any questions (i.e. invoke your right to “remain silent”).
  • If an officer asks to search your vehicle, politely decline.
  • If an officer asks to search your purse, backpack, jacket, or pockets, politely decline.
  • If an officer asks you to do Standardized Field Sobriety Tests (SFTs), politely decline.
  • If you are arrested and asked to provide a urine test, demand an opportunity to contact or attempt to contact an attorney/lawyer.
  • If you are formally charged with DUI, contact an attorney immediately.
Oregon Marijuana DUI Lawyer and Attorney
Oregon Marijuana DUI Attorney Michael Romano is a lawyer with the experience to defend drivers from false allegations of driving while under the influence of cannabis.

Michael Romano – Oregon Marijuana DUI Attorney

If you’ve been arrested in Oregon for a marijuana DUI, contact an experienced Oregon DUI lawyer immediately. Our office would be happy to assist. Mr. Romano’s approach to Marijuana DUI defense is very practical. We provide knowledgeable, experienced, thorough, and efficient representation in DUI cases– with a diligence and aggressiveness appropriate to the legal & practical consequences to the client, and the client’s personal preferences. In other words, a client who has a diversion-eligible DUI and a strong preference to quickly put the matter behind them may require or desire less work (and expense) than a client who is facing a lifetime revocation of their driving privileges, a felony DUI, or possible loss of employment. Mr. Romano does not recommend that every case proceed to a motion to suppress or trial, but Mr. Romano has received “not guilty” verdicts (aka acquittals) for clients accused of being under the influence of marijuana, and with BACs (blood alcohol content readings) ranging from .08 to .26. Simply put: We have the ability and desire to help all drivers facing a DUI charge in Oregon.

Call our offices in Portland (503-208-5529) or Bend (541-382-4404) to schedule an initial consultation by video conference, in-person, or by telephone.

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