Marijuana DUIs in Colorado: What You Need to Know if You’ve Been Pulled Over in the Four Corners

May 30

Even though recreational marijuana is legal in Colorado, driving while impaired by it is not. And if you’re pulled over near Durango, Cortez, or anywhere in the Four Corners region, you can be arrested and charged with a DUI—just like alcohol.

At the Victor Titus Law Firm, we help good people who’ve found themselves in bad situations. If you’re facing marijuana DUI charges in Colorado, here’s what you need to know.

Is There a Legal Limit for THC in Colorado?

Yes, but it’s not as simple as a “safe” number.

In Colorado, if your blood contains 5 nanograms or more of delta-9-THC per milliliter, prosecutors may use that as evidence that you were impaired. But this standard is controversial and imprecise.

Why? Because THC is stored in fat cells and can stay in your body long after the high has worn off—especially if you’re a regular user. So a person could test well above 5 ng/mL and not be impaired at all.

How Do Officers Test for Marijuana Impairment?

There is no breathalyzer for weed—not yet. So instead, Colorado officers rely on a combination of methods, including:

Field Sobriety Tests (FSTs) – like walking a straight line, balancing on one leg, or following a pen with your eyes
Oral fluid swabs – to check for THC or other drugs
Blood tests – to detect THC and its metabolites
Officer observations – slurred speech, red eyes, slow movements, marijuana odor, or erratic driving

Some officers are trained as Drug Recognition Experts (DREs) and may conduct additional evaluations on the roadside or at the station.

Are These Tests Reliable?

Not always.

THC levels don’t always correlate with real-time impairment
Field tests are designed for alcohol, not cannabis
Oral swabs and blood tests can detect use from hours to days ago, not necessarily impairment
Officer observations are subjective—and can be challenged in court

That’s why your defense matters. There may be major weaknesses in the state’s case.

What Are the Penalties for Marijuana DUI in Colorado?

A first-time conviction for marijuana DUI in Colorado can lead to:

5 days to 1 year in jail
$600–$1,000 in fines
Community service
Mandatory drug education and treatment
Loss of driving privileges

And those penalties get steeper with each subsequent offense. If there are aggravating factors—like prior DUI convictions, minors in the car, or accidents—the consequences can include felony charges and prison time.

Can You Be Arrested Without a Test?

Yes. You can be arrested solely based on officer observations. For example:

You admit to recent marijuana use
There’s a strong smell of weed in the car
You have red eyes or slurred speech
You fail a field sobriety test
Paraphernalia is visible in the vehicle

You do have rights, but refusing a test can result in automatic license suspension under Colorado’s Express Consent law.

What Should You Do If You’ve Been Arrested?

Call an experienced DUI defense attorney as soon as you can.

At the Victor Titus Law Firm, we know how to navigate DUI cases in La Plata, Montezuma, and Archuleta counties. We’ll investigate the validity of your arrest, the accuracy of testing, and whether your rights were violated. In many cases, we can challenge the evidence or negotiate for reduced penalties.

Call (505) 326-6503 today for a free consultation. We’re based in Farmington and proudly serve clients across Southwest Colorado who need strong defense and honest legal support.

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