Marijuana DUIs in Denver: How Colorado Police Determine Impairment

Since Colorado legalized recreational marijuana, Denver has seen a significant increase in marijuana-related DUI cases. At Mile High Legal, our Denver criminal defense attorneys have become leaders in defending these complex cases throughout the Denver metro area.

Unlike alcohol, where Colorado law sets a specific BAC limit (0.08%), marijuana impairment is determined differently. Under C.R.S. § 42-4-1301(6)(a)(IV), Colorado has established a permissive inference of impairment at 5 nanograms of THC per milliliter of whole blood—but proving impairment remains challenging for prosecutors.

Here's how Denver police typically determine marijuana impairment:

1. Specialized Drug Recognition Experts (DREs): Denver Police Department has invested heavily in training officers as DREs who perform a 12-step evaluation

2. Roadside Sobriety Tests: Modified to detect marijuana impairment, though these tests are often unreliable at locations throughout Denver

3. Blood Testing: Ordered after arrest, though THC blood levels don't correlate with impairment the way alcohol does

4. Observational Evidence: Officers document physical signs like red eyes, the odor of marijuana, or the presence of paraphernalia

Our Denver defense team has successfully challenged marijuana DUI charges by:

• Questioning the scientific validity of the 5 nanogram threshold

• Highlighting improper DRE procedures in Denver and surrounding jurisdictions

• Demonstrating that regular medical marijuana users may have high THC levels without impairment

• Showing that many Denver officers lack proper training to identify marijuana impairment

Mile High Legal has defended hundreds of marijuana DUI cases from Downtown Denver to the Tech Center, and we understand the evolving nature of these prosecutions in different Colorado courts.

For medical marijuana patients, Colorado law provides some additional considerations, though not complete protection from DUI charges.

If you're facing a marijuana DUI in Denver or anywhere in Colorado, contact Mile High Legal for a defense strategy that addresses the unique aspects of these cases, including the scientific challenges to proving marijuana impairment.