Here are five key things to know:
- Chemical breath and blood tests are also called “evidentiary tests.” This is because chemical tests come into evidence if your DUI case goes to trial.
- In contrast, the preliminary roadside breath test is just a tool police use to see if they have probable cause to arrest you for DUI.
- If you refuse a chemical test, you can usually resume driving after only two months if you get an IID and complete the alcohol/drug program.
- Refusing the chemical test will cause your license to be revoked even if your DUI charges get dropped.
- If you pick up another DUI and refuse the chemical test again, your license suspension will last longer, as this chart shows:
|
Refusal to Take a Chemical Test After a DUI Arrest |
License Suspension Period in Colorado |
| 1st time | 1 year |
| 2nd time | 2 years |
| 3rd or subsequent time | 3 years |
- 1. Pre-DUI Arrest
- 2. Post-DUI Arrest
- 3. Penalties
- 4. Should I refuse anyway?
- 5. Fighting the License Suspension
- Frequently Asked Questions
- Additional Reading
1. Pre-DUI Arrest
When a law enforcement officer pulls you over in Colorado, first, they observe you for signs of intoxication, such as:- the odor of alcohol or marijuana,
- bloodshot and glassy eyes,
- slurred speech,
- an admission that you have been drinking or doing drugs, and
- fumbling while retrieving your license, registration, and insurance.
| Colorado DUI Crime | Illegal BAC |
| DUI per se (driving under the influence) | 0.08% and higher |
| DWAI (driving with ability impaired) | Above 0.05% to less than 0.08% |
| Commercial DUI | 0.04% and higher |
| UDD (underage drinking and driving) | 0.02% and higher |
- the one-legged stand,
- the walk-and-turn, and
- the horizontal gaze nystagmus (eye test).
2. Post-DUI Arrest
As a driver in Colorado, you are presumed to give your “express consent” (also called implied consent) to take an evidentiary chemical test following an arrest for DUI, DWAI or underage DUI. Therefore, you cannot legally refuse the test. You do have a choice to take either a breath test or a blood test to measure your BAC. This test should occur within two hours of your driving. (In rare cases, police ask for saliva or urine.) The advantage of breath tests is that they deliver immediate results. Although more accurate than preliminary breath tests, they are less reliable than blood tests. Meanwhile, blood tests can be painful, and it takes weeks to get results. Note that if police suspect you of drugged driving, you must take the blood test. This is because breath tests do not detect drugs, only alcohol.13. Penalties
Refusing the chemical breath or blood test following a drunk/drugged driving arrest in Colorado carries three main consequences: The first is a one-year revocation of your Colorado driver’s license. However, you can apply for reinstatement of your driving privileges after only two months if you take a Level II Alcohol and Drug Education and Treatment program and get an IID (ignition interlock device) installed in your car. Note that if you have a prior refusal, your license revocation will be for two years. If you have two or more prior refusals, the revocation will remain in effect for three years.7 The second consequence is that you will be designated as a “persistent drunk driver” (PDD) even if your BAC is below the typical PDD minimum of 0.15%. As a PDD, you must:- Take a Level II Alcohol and Drug Education and Treatment program,
- Keep an ignition interlock device in your vehicle for at least two years following the restoration of your driving privileges, and
- Carry SR-22 insurance for three years even if you are never convicted of DUI.
DUI Penalties
Remember, the penalties for refusing are separate from any penalties you face if you are convicted of DUI or DWAI. These include fines, jail, community service, and an additional license suspension. Furthermore, having a DUI on your record could hurt your prospects for employment, housing, education, professional licenses, and even friendships. That is why it is so important to hire legal counsel to fight these charges in pursuit of a dismissal or reduction.
4. Should I refuse anyway?
One advantage of refusing a chemical test following a DUI arrest is that there will be no proof of your BAC. On the other hand, you can still be charged with DUI or DWAI based on your actual driving and other external evidence of inebriation. Then, of course, many of the consequences for refusing are more serious than an actual DUI or DWAI conviction, especially if it is your first. For instance, the license revocation for a first-time refusal (one year) is three months longer than that for a first-time DUI (nine months).4 In addition, if you choose to take a chemical test, there are various ways to challenge the results. For example, you can argue that:- The breathalyzer was not calibrated correctly: Breathalyzers are known to deliver results that may be off by .005% to .02%.
- Your blood sample was contaminated in the lab: Possibly, it could have been switched with someone else’s.
- You had a medical condition that caused a falsely high breathalyzer result. Examples include GERD or acid reflux.
5. Fighting the License Suspension
If you refuse a chemical test following a Colorado DUI arrest, the officer will confiscate your license and replace it with a seven-day temporary driving permit. If you wish to contest the license revocation, you (or your attorney) must request an administrative hearing with the DMV during that time. If you do request a hearing within those seven days, you can continue driving pending the results of the hearing. Otherwise, the revocation will kick in on the seventh day. DMV hearings are actually more difficult to win than criminal trials. This is because the DMV can revoke your license based on only a preponderance of the evidence. In contrast, criminal courts require proof beyond a reasonable doubt before you can be convicted.6 Still, DMV hearings are worth doing. Sometimes, evidence comes out during the DMV hearing that you can use in your favor during the criminal case.Common Defenses
Here at Colorado Legal Defense Group, we have represented literally thousands of DUI defendants accused of refusing the chemical test. In our experience, the following four defenses can be very effective at persuading DMV hearing officers to let you keep your license.- You never refused the test. Maybe the police misconstrued your words as a refusal or even lied about you refusing.
- Your refusal was beyond your control. For example, perhaps someone had spiked your drink and you were involuntarily intoxicated. Or perhaps you were suffering from a head injury, epilepsy, or another condition that caused you not to be in your right mind. (This “beyond your control” defense applies only when you did nothing to cause yourself to lose control. If you were voluntarily intoxicated, this defense will not work.)7
- The DUI arrest was illegal to begin with. If the police lacked probable cause to believe you were driving under the influence, then the arrest should not have occurred, and your refusal was moot. Helpful evidence in these cases is the police’s dashcam and bodycam footage of what led up to your arrest.
- You suffered from “legal confusion.” If an officer reads you your Miranda rights but fails to clarify that you have no right to an attorney specifically for the chemical test decision, any subsequent refusal may be deemed invalid if you were genuinely confused about your legal rights.8

Frequently Asked Questions
Is it a crime to refuse the handheld breathalyzer at the roadside?
No. In Colorado, “Preliminary Breath Tests” (PBTs) and Field Sobriety Tests (FSTs) performed at the side of the road are 100% voluntary. You can politely refuse these tests without facing a license suspension or any DMV penalties. These tests are primarily tools used by officers to build “probable cause” for an arrest; refusing them prevents the prosecution from using subjective “failed” coordination tests against you in court.What is the difference between a breath test and a blood test at the station?
Once you are arrested, you must choose between a breath or blood test under the Express Consent law. Breath tests provide immediate results but are more susceptible to “false positives” due to machine calibration or physiological factors. Blood tests are significantly more accurate and reliable, but because the results take weeks to process, you may be able to keep your physical license for a short period while waiting for the results and your subsequent DMV hearing.If I refuse a test, am I automatically labeled a “Persistent Drunk Driver”?
Yes. Under C.R.S. 42-1-102(68), any person who refuses a chemical test is automatically designated a “Persistent Drunk Driver” (PDD), even for a first-time offense. This label is permanent and triggers harsher requirements, including a mandatory two-year ignition interlock period and the requirement to carry high-risk SR-22 insurance for at least two to three years.Can I win my DMV hearing if I was “legally confused” about my rights?
Potentially. If an officer reads you your Miranda rights (the right to remain silent and have an attorney) but fails to clarify that you have no right to an attorney for the chemical test decision, you may have a “Legal Confusion” defense. This lack of clarity led you to refuse the test because you were waiting for a lawyer, a judge may rule the refusal invalid and reinstate your driving privileges.Is it ever strategically better to refuse the test if I have prior DUIs?
If you have multiple prior convictions, a high-BAC result (above .15% or .20%) can lead to mandatory jail time and a permanent felony record. Some people argue that accepting the one-year administrative license revocation for a refusal is the “lesser of two evils” compared to providing the prosecution with the “per se” evidence needed to secure a lengthy prison sentence. However, considering the police can obtain a warrant to force you to submit to a blood draw if you refuse, it is usually in your best interest to submit to a chemical test without resistance. They are going to get your BAC results one way or another.Additional Reading
For more in-depth information, refer to these scholarly articles:- The Privacy Implications of DUI Refusals and Forced Blood Alcohol Tests: What Judges Can Do – Criminal Justice.
- Shed Thou No Blood: The Forcible Removal of Blood Samples from Drunk Driving Suspects – California Law Review.
- Do I Really Have a Choice – Compulsory Blood Tests on Drunk Drivers and the Fourth Amendment – Western State University Law Review.
- Drunk Driving, Implied Consent, and Self-Incrimination – The Journal of the American Academy of Psychiatry and the Law.
- Taking Blood Evidence for Granted: McNeely and Birchfield’s Unintended Consequences – Stanford Law School.
Legal References:
- C.R.S. 42-4-1301. Standards for the Standardized Field Sobriety Testing (SFST) Program, Colorado Department of Transportation.
- C.R.S. 42-4-1301.1. Expressed consent for the taking of blood, breath, urine, or saliva sample – testing.
(1) Any person who drives any motor vehicle upon the streets and highways and elsewhere throughout this state shall be deemed to have expressed such person’s consent to the provisions of this section. (2) (a) (I) A person who drives a motor vehicle upon the streets and highways and elsewhere throughout this state shall be required to take and complete, and to cooperate in the taking and completing of, any test or tests of the person’s breath or blood for the purpose of determining the alcoholic content of the person’s blood or breath when so requested and directed by a law enforcement officer having probable cause to believe that the person was driving a motor vehicle in violation of the prohibitions against DUI, DUI per se, DWAI, or UDD. Except as otherwise provided in this section, if a person who is twenty-one years of age or older requests that the test be a blood test, then the test shall be of his or her blood; but, if the person requests that a specimen of his or her blood not be drawn, then a specimen of the person’s breath shall be obtained and tested. A person who is under twenty-one years of age shall be entitled to request a blood test unless the alleged violation is UDD, in which case a specimen of the person’s breath shall be obtained and tested, except as provided in subparagraph (II) of this paragraph (a).
- C.R.S. 42-2-126, C.R.S. 42-2-132.5. See Colorado Department of Revenue, Division of Motor Vehicles, SR-22 and Insurance Information. C.R.S. 42-1-102(68.5)(a). C.R.S. 42-4-1301(6)(d).
- C.R.S. 42-2-126.
- Missouri v. McNeely (2013) 569 U.S. 141, 133 S. Ct. 1552.
- C.R.S. 42-2-126.
- C.R.S. 18-1-804. People v. Grenier (Colo. 2008) 200 P.3d 1062
- Calvert v. State Dep’t of Revenue (Colo. 1974) 623 P.2d 871.