If you’ve been pulled over in Denver or anywhere else in Colorado, one of the first things that may cross your mind is whether you can refuse a breathalyzer in Colorado. It’s a fair question — and at Baker Law Group, PLLC, it’s one we hear often. Knowing the answer before you’re in that situation can make a serious difference in what happens next.
The short answer is yes, you can refuse. But refusal comes with real, automatic consequences under state law. This page breaks down what those consequences are, how the law works, and what your options look like if you’ve already been stopped or charged.
Colorado Breathalyzer Law: What Drivers Need to Know
Colorado operates under what’s called the Express Consent Law, outlined in C.R.S. § 42-4-1301.1. By driving on Colorado roads, you automatically agree to submit to a chemical test — either breath or blood — if a law enforcement officer has reasonable suspicion that you’re impaired.
There are two types of tests to be aware of:
- Preliminary Breath Test (PBT): This is the handheld roadside test. Officers use it to establish probable cause. You can decline this test, and the consequence is typically a minor traffic infraction — not a criminal penalty.
- Evidentiary Chemical Test: This is the official test, typically administered following a lawful arrest, usually at the station. This is the one that falls directly under Colorado’s Express Consent Law. Refusing this test triggers automatic, serious penalties.
Colorado breathalyzer law applies to both DUI (Driving Under the Influence) and DWAI (Driving While Ability Impaired) stops. Knowing the difference between these two tests before you’re sitting in a patrol car matters enormously.
What Happens If You Refuse a Breath Test in Colorado
What happens if you refuse a breath test in Colorado depends on your history, but the penalties start immediately — regardless of whether you’re ultimately convicted of DUI.
For a first-time refusal, your driver’s license is automatically revoked for one year. You may qualify for early reinstatement after two months, but only if you install an ignition interlock device on your vehicle. A second refusal carries longer revocation periods and compounds the penalties you’re already facing.
Beyond your license, the refusal itself can be used as evidence against you in a criminal case. Prosecutors often argue that refusing shows a consciousness of guilt — that you knew the test would hurt you. It’s not a slam-dunk argument, but it’s one they will make.
There’s also a deadline most people don’t know about: you have just seven days from your arrest to request a DMV hearing to fight your license revocation. Miss that window, and the revocation becomes automatic. Colorado’s Division of Motor Vehicles and the Denver County Court operate on strict timelines, and acting quickly is essential.
Should You Refuse a Breathalyzer in Colorado?
This is where the nuance lives. Should you refuse a breathalyzer? There’s no clean, universal answer — and anyone who tells you otherwise without knowing your full situation isn’t giving you real legal advice.
Some people refuse because they believe a high BAC result will cause more damage than a refusal. Others distrust the accuracy of the device. Those are legitimate concerns in certain situations. But refusal guarantees penalties, while a high test result may still be challenged in court.
What’s certain is this: if you’ve been stopped on suspicion of DUI in Colorado, having an experienced Denver DUI defense attorney involved early changes what’s possible. The right attorney can assess whether the stop was legally valid, whether the test was administered correctly, and what defense strategy fits your specific facts.
How to Challenge a Breathalyzer Test
Submitting to a breath test doesn’t mean the results are beyond question. There are several legitimate ways to challenge a breathalyzer test, and experienced defense attorneys use them regularly:
- Device calibration issues: Breathalyzer machines must be properly maintained and calibrated on a set schedule. If the machine wasn’t serviced correctly, the results may not hold up.
- Officer certification: The officer administering the test must hold proper certification. Gaps in their training or procedure can create grounds for a challenge.
- Mouth alcohol contamination: Residual alcohol from mouthwash, certain medications, or acid reflux can cause a falsely elevated reading.
- Medical conditions: Conditions like diabetes or GERD can interfere with breath test accuracy in ways that mimic intoxication.
- Improper observation period: Colorado law requires officers to observe you for at least 20 minutes before the test to rule out contamination factors. If they skipped or shortened that window, the results may be challenged.
Knowing how to challenge a breathalyzer test requires a detailed review of the arrest records, the device maintenance logs, and the officer’s conduct during the stop — all things Baker Law Group, PLLC examines closely for every client.
A Charge Is Not a Conviction
Whether you refused or submitted to a test, being charged with DUI is not the same as being convicted. Colorado DUI penalties are serious — fines, jail time, license suspension, mandatory alcohol education programs — but none of it is guaranteed the moment handcuffs go on.
Every case has facts. Facts can be challenged. Baker Law Group, PLLC works with clients facing DUI charges in Denver and across Colorado, taking a direct and strategic approach to each case from the very first call.
Denver DUI Defense Attorney Ready to Stand in Your Corner
If you’re trying to figure out whether you can refuse a breathalyzer in Colorado — or you’ve already been arrested and need to understand what happens next — don’t wait. The seven-day window to request your DMV hearing can close before you realize it’s gone.
Contact Baker Law Group, PLLC today to speak with a Denver DUI defense attorney who will review your situation honestly, explain your legal options clearly, and start building your defense from day one. Call us or fill out our contact form to schedule your consultation.
