Most people charged with a drunk driving offense in Colorado assume they are all the same charge under a different name, but that assumption can cost you dearly. Colorado law actually recognizes two distinct DUI offenses, each built on a different legal standard, and understanding the difference matters enormously when building your defense.
If you are facing either type of charge, having a knowledgeable Denver DUI defense attorney in your corner is critical. At Shazam Kianpour & Associates, P.C., we have defended thousands of clients against DUI charges across Colorado and the Denver Front Range, and we know how prosecutors approach both types of cases.
What Does “DUI” Mean Under Colorado Law?
In Colorado, a standard DUI charge is based on impairment. Under C.R.S. § 42-4-1301(1)(f), driving under the influence means operating a vehicle after consuming alcohol, drugs, or a combination of both to a degree that leaves the driver substantially incapable, mentally or physically, of exercising clear judgment, sufficient physical control, or due care in the safe operation of a vehicle.
The key word here is “substantially.” Prosecutors pursuing a standard DUI do not need to present a blood or breath test result to obtain a conviction. Instead, they build their case on observable evidence gathered at the scene. This evidence can include a law enforcement officer’s testimony about your driving behavior, the results of field sobriety tests, physical indicators like slurred speech or the odor of alcohol, and any statements you made during the stop.
Why the Impairment Standard Matters
This means a person can be convicted of DUI in Colorado even if their blood alcohol content (BAC) was below 0.08%. If the totality of the evidence demonstrates substantial impairment, a jury may find guilt regardless of what a chemical test shows. This is especially relevant in cases involving drugs, prescription medications, or situations where a test was refused or produced an inconclusive result.
Understanding this distinction is also essential in cases involving cannabis. Colorado law allows prosecutors to pursue DUI charges based on drug impairment even without a blood test confirming a specific THC level. The argument centers entirely on whether the driver’s ability was substantially compromised.
What Is “DUI Per Se” in Colorado?
DUI per se is a separate charge under C.R.S. § 42-4-1301(2)(a). Unlike a standard DUI, DUI per se does not require proof of actual impairment. Instead, it is triggered automatically when a driver’s BAC measures 0.08% or higher at the time of driving, or within two hours of driving. The Colorado DMV defines DUI per se as driving with a BAC of 0.08 or more, and the statute incorporates this standard directly by reference.
The significance of this charge is that the chemical test result alone is enough to sustain a conviction. Prosecutors do not need to prove the driver appeared drunk, drove erratically, or failed any roadside tests. If the number on the test meets or exceeds the threshold, the per se standard is satisfied. This makes the accuracy and integrity of the chemical testing process a central focus in any defense of a DUI per se charge.
Challenging the Test in a DUI Per Se Case
Because the BAC result is essentially the cornerstone of the prosecution’s case, there are meaningful opportunities to challenge it. Defense strategies often focus on whether the breathalyzer was properly calibrated and certified, whether the blood draw was handled correctly and stored under appropriate conditions, and whether the two-hour window between driving and testing was properly documented. Colorado courts have acknowledged the unreliability of faulty DUI tests in a number of cases, and a successful challenge to the testing process can significantly alter the outcome.
Can You Face Both Charges at the Same Time?
Yes. Colorado prosecutors commonly charge both standard DUI and DUI per se arising from the same traffic stop. This is a standard prosecutorial approach designed to preserve both theories of guilt in the event one charge is weakened during trial. Even if the defense successfully challenges the reliability of a BAC result, prosecutors may still pursue the standard DUI charge based on observed impairment. Likewise, a clean-looking interaction at the roadside does not eliminate the per se charge if the chemical test produced a qualifying result.
It is also worth noting that DUI and DUI per se carry the same criminal penalties in Colorado. A conviction under either charge exposes you to the same potential jail time, fines, license revocation, and mandatory education requirements. Knowing what to expect in the first 24 hours after a DUI arrest is one of the first steps toward protecting yourself.
Contact Shazam Kianpour & Associates, P.C. Today
Whether you are facing a standard DUI, a DUI per se charge, or both, the legal path forward requires a precise and strategic defense. Shazam Kianpour & Associates, P.C. has more than 22 years of experience defending clients throughout Colorado, and Mr. Kianpour has personally handled thousands of criminal and traffic cases. He graduated with honors from law school, ranked at the top of his class in Criminal Law, and is recognized by both the National Trial Lawyers and Super Lawyers. Our entire team is built around criminal and traffic defense, giving us a depth of knowledge few firms in Denver can match.
Do not wait to get answers about your case. The sooner you have counsel reviewing the facts, the more options may be available to you. Contact us today to schedule a consultation and speak directly with a member of our team.