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Colorado Criminal Defense and Personal Injury Attorneys

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Boulder Criminal Defense and Personal Injury Attorneys

Marijuana DUI


Marijuana DUI


Can I be charged with a DUI simply because I regularly smoke pot?

Because recreational marijuana is legal in Colorado for individuals who are over the age of 21 and medical marijuana is available by prescription for those 18 and older, the question is often asked: As a person who regularly uses marijuana, can I be charged for driving under the influence of marijuana?  The answer is yes.  And if a police officer believes that you were driving while high, the actual criminal charge that can be brought against you is called Driving Under the Influence of Drugs, or DUID

The important distinction is this:  You can only be convicted of DUID related to consuming marijuana if you were impaired while driving.  

In Colorado the “proof” of impairment is often sought by testing your blood to determine the level of delta 9-tetrahydrocannabinol (THC), the psychoactive ingredient found in marijuana.  However, you can be prosecuted for a DUID related to consuming marijuana even if you don’t consent to take a chemical test.  Regardless of whether you consent to a chemical test, an assessment of how you drove before being contacted by police and what admissions you might have made is of critical concern.

The ability to safely drive after consuming marijuana can vary greatly among individuals depending on a host of factors including history of marijuana use, tolerance, dose, strength of the marijuana consumed, and mode of use. Edibles, for example, are associated with a slower onset of intoxication and performance deficits.

In DUID cases where marijuana is the suspected source of impairment, it is critically important that you not discuss the details of your consumption of marijuana with police officers who are trained to try and narrow down the window of your marijuana use.  Police officers make this inquiry because there is a crucial difference between the mere presence of THC in your blood and whether any THC present can be shown to have impaired your mind.  The by-products of THC are called “THC metabolites.”  Most testing used by law enforcement generically just looks for THC metabolites. Since THC is a fat-soluble molecule, it can remain inertly in your body for a long time, making testing which simply looks for THC metabolites a terrible measure of impairment.  The key to an accurate assessment of THC impairment by blood testing is whether the test used discriminates for the neuroactive components that get you high and matches up with the known science on how long those metabolites remain active for purposes of impairment. 

Where appropriate, your Mertes Law DUIDUID lawyers employ experienced toxicologists to explain how impairment from marijuana typically occurs within four hours following use, how long-term marijuana use confounds current testing protocols, how testing procedures fail to provide answers to the question of impairment, and other factors that weigh upon whether you can be found guilty beyond a reasonable doubt for a DUID charge.

What type of tests do officers perform to assess the presence of marijuana impairment in a DUI case?

If a police officer believes that you are under the influence of drugs and/or alcohol, he or she will often request that you submit to expanded roadside sobriety testing known as Advanced Roadside Impaired Driving Enforcement (ARIDE) by a police officer trained as a Drug Recognition Expert (DRE). DREs learn to differentiate the effects of different classes of drugs such as central nervous system depressants (e.g. alcohol, barbiturates), central nervous system stimulants (e.g. cocaine, amphetamine, methamphetamine), disassociative anesthetics (e.g. PCP, Ketamine), narcotic analgesics (e.g. heroin, morphine, codeine), inhalants (e.g. paint, glue, nitrous oxide), and marijuana.

By way of example, a DRE examination focused on marijuana impairment will look to see if you have reddened eyes, dilated pupils, a lack of visual convergence (e.g. evidence your eyes are not working together when looking at nearby objects causing impaired or blurred vision), an elevated pulse rate, and elevated blood pressure.

If you consent to expanded roadside sobriety testing by a DRE, you are in store for a lengthy medical-type examination that may last hours since the testing protocols are often repeated.  This over-the-top evaluation of your eye function, balance, respiration, cognition, and balance can only occur if you give your consent.  And DRE evaluations frequently fail to identify other medical diagnoses that should be considered prior to calling any symptom “proof” of impairment.  In the repurposed words of former First Lady Nancy Reagan: “just say no” if you are asked to submit to regular or expanded roadside testing by a DRE. 

If a police officer suspects you of DUID in Colorado, you will be asked to submit to a blood test. However, in a majority of DUID cases, officers will often first try to assess what amount of alcohol you have in your system.  They typically do this by offering you a breath or blood test.  If you take a breath test and the results indicate that you are not impaired or intoxicated, a police officer who still suspects that you are impaired may ask you to consent to a second test of your blood to evaluate you for drug use, including marijuana.  Refusing any chemical test requested by a police officer will have negative consequences on your driver’s license and your right to drive.  And in Colorado, juries are told that you refused to be tested.

How does Colorado assess impairment when the “drug” is Marijuana?

The Colorado legislature has settled upon a largely criticized measure of five (5) nanograms of delta 9-tetrahydrocannabinol (THC) per milliliter in whole blood as giving rise to a “permissible inference” that a driver was impaired.  But the ultimate decision on impairment to prove a DUID charge remains with a judge or jury.

The National Highway Traffic Safety Administration (NHTSA) is one of many critics of the 5 nanogram THC level, as they question the limits as being artificial and not science based.

The attorneys at Mertes Law are former DUI prosecutors who have  successfully defended clients charged with DUI and DUID offenses throughout Boulder County, Colorado, including the cities of Boulder, Longmont, Erie, Louisville, Lafayette, and Superior in addition to the Front Range of Colorado. 

Mertes LawIf you are arrested for driving while high and charged with a marijuana DUI or DUID, you need an attorney who is conversant about marijuana and capable of understanding how to defend you against a criminal charge that is often raised when your only “crime” is the legal use of marijuana.  Your Mertes Law Boulder criminal defense lawyer can begin building a solid defense against this serious charge using experts in toxicology and medicine to help a judge or jury understand the critical issues surrounding marijuana impairment.

Call us today at 303-440-0123 for a free consultation.   

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