Refusing Field Sobriety Tests in Colorado: Can You Say No?

If you’re stopped for suspected DUI in Colorado, one of the most confusing moments happens when the officer asks you to step out of the vehicle and perform roadside tests. You might wonder: “Do I have to do this?” The short answer is no, but understanding your rights and the potential consequences is crucial to making an informed decision.

At Right Law Group, our Colorado DUI defense attorneys have represented countless clients who faced this exact situation. Based on that experience, we know that many people agree to field sobriety tests without understanding they’re voluntary or how significantly these tests can impact their case. 

This guide explains your legal right to refuse field sobriety tests in Colorado and what you should consider before making that decision.

Quick Answer: You Can Refuse Field Sobriety Tests in Colorado

Colorado law allows you to refuse field sobriety tests without criminal penalty. Unlike refusing a chemical breath or blood test after arrest, declining to perform roadside field sobriety tests does not result in automatic license suspension or additional criminal charges.

However, your refusal can be used as evidence in court, and officers may still arrest you based on other observations. Understanding both your rights and the practical implications of refusal is essential when facing this decision.

What Are Field Sobriety Tests?

Field sobriety tests (FSTs), also called Standardized Field Sobriety Tests (SFSTs), are physical and cognitive exercises that law enforcement uses to evaluate whether a driver is impaired. Officers typically administer these tests on the roadside after a traffic stop when they suspect alcohol or drug impairment.

The National Highway Traffic Safety Administration (NHTSA) has established three standardized field sobriety tests used by Colorado law enforcement:

The Three Standardized Field Sobriety Tests

Horizontal Gaze Nystagmus (HGN) Test

The officer holds an object (usually a pen or flashlight) approximately 12-15 inches from your face and asks you to follow it with your eyes while keeping your head still. The officer looks for involuntary jerking movements of the eyes, which can indicate impairment. This is often called the “follow my pen” test.

Walk-and-Turn Test

You must walk heel-to-toe along a straight line for nine steps, pivot on one foot, and return nine steps in the opposite direction. The officer watches for specific indicators such as:

• Starting before instructions are complete
• Losing balance while listening to instructions
• Stopping while walking
• Not touching heel-to-toe
• Stepping off the line
• Using arms for balance
• Making an improper turn
• Taking the wrong number of steps

One-Leg Stand Test

You stand on one foot with the other foot raised approximately six inches off the ground while counting aloud for thirty seconds. Officers look for swaying, using arms for balance, hopping, or putting the foot down during the test.

Non-Standardized Tests

Officers may also request non-standardized tests, such as:

• Reciting the alphabet
• Counting backward
• Touching your finger to your nose
• Standing on one foot and tilting your head back

These non-standardized tests are even less reliable than the standardized tests and are often easier to challenge in court.

Field Sobriety Tests vs. Chemical Tests: Understanding the Critical Difference

Many people confuse field sobriety tests with chemical tests, but they are completely different with vastly different consequences for refusal.

Field Sobriety Tests (FSTs)

• Voluntary in Colorado
• No automatic penalties for refusing
• Performed on the roadside before arrest
• Physical and cognitive exercises
• Subjective evaluation by officer
• Refusal can be mentioned in court but carries no legal penalty

Chemical Tests (Breath or Blood)

• Required under Colorado’s Express Consent law after arrest
• Automatic license suspension for refusing (1 year for first refusal, 2 years for second, 3 years for third and subsequent)
• Performed after arrest at police station or medical facility
• Scientific measurement of blood alcohol content
• Objective numerical results
• Refusal triggers immediate DMV penalties separate from criminal charges

Preliminary Breath Test (PBT)

• Handheld roadside device
• Voluntary before arrest
• NOT admissible in court
• Used only to establish probable cause for arrest
• No penalty for refusing

What to Do After a DUI Arrest in Colorado: Your First 24-48 Hours provides comprehensive information about your rights during a drug-related arrest, including your right to refuse various tests and searches.

Your Legal Right to Refuse Field Sobriety Tests in Colorado

Colorado law explicitly recognizes your right to decline field sobriety tests. When an officer asks you to perform these tests, you can politely refuse without facing criminal charges or automatic administrative penalties.

The key legal principle is that field sobriety tests are considered voluntary interactions before arrest. You are not legally required to provide evidence against yourself, and the Fifth Amendment protects you from self-incrimination.

How to Refuse Politely and Clearly

If you decide to refuse field sobriety tests, clarity and courtesy are important:

Say clearly: “Officer, I respectfully decline to perform any field sobriety tests. I’d like to speak with an attorney.”

Do not:

• Make excuses or explanations
• Get argumentative or hostile
• Physically resist or walk away
• Provide lengthy justifications for your refusal

Remember that while you have the right to refuse these tests, you should still comply with lawful orders such as providing your driver’s license and registration or exiting the vehicle if instructed.

Why Field Sobriety Tests Are Notoriously Unreliable

One of the most important facts about field sobriety tests is that they are highly unreliable indicators of impairment. Even the standardized tests recognized by NHTSA have significant accuracy problems.

Accuracy Rates

Research shows that standardized field sobriety tests are only 65-77% accurate at detecting impairment, even under ideal conditions and when administered perfectly. This means that even in the best-case scenario, these tests incorrectly identify sober people as impaired 23-35% of the time.

In real-world conditions on the side of the road at night, with stress, poor lighting, and uneven surfaces, the error rate is likely much higher.

Factors That Affect Field Sobriety Test Performance

Many completely innocent factors can cause a sober person to “fail” field sobriety tests:

Physical Conditions:

• Age (people over 65 have difficulty with balance tests)
• Weight (people more than 50 pounds overweight struggle with balance)
• Inner ear problems or vertigo
• Injuries to legs, back, or knees
• Neurological conditions
• Vision problems
• Fatigue

Environmental Factors:

• Uneven or sloped road surfaces
• Gravel, dirt, or wet pavement
• Poor lighting at night
• Bad weather (wind, rain, snow)
• Traffic and noise creating stress
• Flashing police lights causing disorientation

Footwear:

• High heels
• Boots
• Flip-flops or sandals
• Dress shoes with slick soles

Psychological Factors:

• Nervousness and anxiety
• Fear of police
• Intimidation from the officer’s demeanor
• Difficulty understanding complex instructions

Subjectivity in Officer Evaluation

Unlike a breath test that produces a numerical result, field sobriety tests depend entirely on the officer’s subjective interpretation of your performance. Two officers watching the same test might reach different conclusions about whether someone “passed” or “failed.”

Officers are trained to look for “clues” or indicators of impairment, and they often document these observations in ways that support their decision to arrest. Once an officer suspects impairment, confirmation bias may cause them to interpret innocent behaviors as signs of intoxication.

The Consequences of Refusing Field Sobriety Tests

While refusing field sobriety tests carries no criminal penalty, your refusal does have practical consequences you should understand.

What Happens When You Refuse

The officer may arrest you anyway. Your refusal to perform field sobriety tests does not prevent arrest. If the officer has probable cause based on other observations (such as the odor of alcohol, bloodshot eyes, slurred speech, or your driving behavior) they can arrest you for DUI without field sobriety test results.

Your refusal can be mentioned at trial. Prosecutors are permitted to tell the jury that you refused to perform field sobriety tests. They may argue that your refusal suggests “consciousness of guilt” that you knew you were impaired and didn’t want to provide evidence.

You may face additional scrutiny. Some officers become more suspicious when drivers refuse tests and may spend additional time looking for other signs of impairment to justify arrest.

What Does NOT Happen When You Refuse

No automatic license suspension. Unlike refusing a chemical test after arrest, refusing field sobriety tests does not trigger DMV action against your driver’s license.

No additional criminal charges. You cannot be charged with a crime for declining to perform voluntary roadside tests.

No increased penalties. Your potential sentence if convicted of DUI is not enhanced because you refused field sobriety tests.

The Consequences of Performing Field Sobriety Tests

Understanding what happens if you do agree to field sobriety tests is equally important.

You’re Creating Evidence Against Yourself

Every movement, every wobble, every time you lose count or step off the line becomes documented evidence that prosecutors will use against you. Even if you believe you performed well, the officer’s report will likely describe numerous “clues” of impairment.

“Passing” Doesn’t Prevent Arrest

Many people think if they perform the tests well, they’ll be allowed to leave. This is almost never what happens. By the time an officer asks you to perform field sobriety tests, they usually have already decided to arrest you. The tests simply provide additional evidence for their report.

The Tests Are Designed to Be Difficult

These tests are challenging even for sober people. They require you to:

• Listen to complex instructions while stressed
• Perform unfamiliar physical tasks
• Maintain balance in difficult conditions
• Divide your attention between multiple requirements

The tests are specifically designed to be hard to complete perfectly, giving officers multiple opportunities to document “clues” of impairment.

How Field Sobriety Test Results Are Used in Court

If you perform field sobriety tests, the results become a central piece of evidence in your DUI case.

The Prosecution’s Strategy

Prosecutors will use field sobriety test results to argue:

• You showed multiple signs of impairment
• The officer’s training qualifies them to identify intoxication
• Your performance on standardized tests correlates with impairment
• The totality of evidence supports a DUI conviction

They’ll present the officer’s testimony describing every mistake you made, often accompanied by dashcam or body camera footage showing your performance.

The Defense Strategy

Experienced DUI defense attorneys can challenge field sobriety test evidence in multiple ways:

Questioning Administration: Were the tests administered according to NHTSA standards? Did the officer give proper instructions? Was the testing environment appropriate?

Highlighting External Factors: Did weather, road conditions, footwear, age, weight, or medical conditions affect your performance?

Challenging Officer Qualifications: Is the officer properly trained and certified? Did they correctly identify and count “clues”?

Demonstrating Unreliability: Emphasizing the inherently subjective nature of these tests and their documented inaccuracy rates.

Showing Alternative Explanations: Demonstrating that nervousness, fatigue, or physical conditions, not impairment, caused any difficulties.

Making the Decision: Should You Refuse Field Sobriety Tests?

The decision to refuse or perform field sobriety tests is ultimately yours, but here are key considerations:

Factors Supporting Refusal

• You know you had something to drink. Even small amounts of alcohol can affect balance and coordination, causing you to perform poorly on FSTs even if you’re not legally impaired.
• You have physical limitations. Injuries, medical conditions, age, or weight make it unlikely you’ll perform these difficult tests successfully.
• Environmental conditions are poor. Bad weather, uneven surfaces, poor lighting, or inappropriate footwear make successful performance nearly impossible.
• You’re extremely nervous. Anxiety alone can cause people to struggle with these tests, regardless of sobriety.

Factors Supporting Compliance

• You have consumed zero alcohol and zero drugs. If you’re completely sober with no substances in your system, you might perform well enough that the officer releases you, though this is not guaranteed.
• You want to appear cooperative. Some people feel that refusing seems confrontational or suggests guilt.

Field Sobriety Tests at DUI Checkpoints

DUI checkpoints present a special situation where understanding your rights regarding field sobriety tests is especially important.

At a legal Colorado DUI checkpoint, you must stop when directed by law enforcement. However, you maintain the same rights as during any traffic stop:

• You can refuse field sobriety tests without penalty
• You can refuse preliminary breath tests
• You should provide your license and registration
• You can politely decline to answer questions beyond identification

If an officer at a checkpoint suspects you’re impaired and asks you to pull to the secondary screening area, the same rules apply regarding your right to refuse field sobriety tests.

What to Do After Refusing Field Sobriety Tests

If you refuse field sobriety tests and are arrested for DUI, take these important steps:

1. Remain Calm and Courteous Continue to be respectful even after arrest. Anything you say or do can be used as evidence of impairment or consciousness of guilt.
2. Invoke Your Right to Remain Silent Clearly state: “I am invoking my right to remain silent and my right to an attorney.” Then stop talking except to provide required identification information.
3. Decide About the Chemical Test After arrest, Colorado’s Express Consent law requires you to submit to a chemical test (breath or blood). Refusing this test, unlike refusing field sobriety tests, triggers automatic license suspension. Consider carefully before refusing a post-arrest chemical test.
4. Contact a Colorado DUI Defense Attorney Immediately Time is critical in DUI cases. We can begin protecting your rights immediately and help you request a DMV hearing to challenge any license suspension.

How Right Law Group Can Help After a DUI Arrest

If you refused field sobriety tests and were arrested for DUI in Colorado, our experienced defense attorneys can help protect your rights and build a strong defense.

Challenging the Arrest

We’ll examine whether the officer had reasonable suspicion to stop you and probable cause to arrest you without field sobriety test evidence. If your arrest was not supported by sufficient evidence, we can file motions to suppress evidence or dismiss charges.

Defending Against Refusal Evidence

While prosecutors can mention your refusal to perform field sobriety tests, we can argue that:

• Refusal is the exercise of your constitutional right against self-incrimination
• You had legitimate reasons for declining (medical conditions, poor conditions, etc.)
• Refusing unreliable tests is a reasonable choice
• Refusal does not prove impairment or guilt

Comprehensive DUI Defense

Our attorneys examine every aspect of your case:

• Was the traffic stop lawful?
• Were proper procedures followed?
• Were chemical tests administered correctly?
• Are there alternative explanations for officer observations?
• Were your constitutional rights violated?

We’ve successfully defended clients throughout Colorado, including Denver, Colorado Springs, Castle Rock, Highlands Ranch, and throughout Arapahoe, Douglas, El Paso, Fremont, Jefferson, Pueblo, and Teller counties.

Frequently Asked Questions

Can I be charged with refusing field sobriety tests?

No. Field sobriety tests are voluntary, and refusing them is not a criminal offense in Colorado.

Will refusing field sobriety tests hurt my case?

Prosecutors can mention your refusal at trial, but refusing eliminates potentially incriminating evidence that could hurt your case more. An experienced attorney may be able to effectively address any inference drawn from refusal.

What if the officer says I have to perform the tests?

Officers sometimes imply that field sobriety tests are mandatory. They are not. You can politely but firmly decline: “I respectfully decline to perform any field sobriety tests.”

Can I refuse some tests but not others?

Yes. You can refuse all tests, agree to all tests, or refuse some while agreeing to others. However, refusing all field sobriety tests is typically the most protective approach.

What’s the difference between refusing field sobriety tests and refusing a breathalyzer?

Field sobriety tests are voluntary roadside physical tests with no penalty for refusal. A breathalyzer or blood test after arrest is required under Express Consent law, and refusing triggers automatic license suspension for at least one year.

If I refuse field sobriety tests, will I definitely be arrested?

Not necessarily, but if the officer has already developed suspicion based on your driving, the odor of alcohol, slurred speech, or other observations, they may arrest you anyway. Your refusal to perform FSTs does not create probable cause for arrest by itself.

Can I change my mind after initially agreeing to field sobriety tests?

Yes. If you begin performing tests and decide to stop, you can clearly state that you no longer wish to continue. However, any performance up to that point can still be used as evidence.

Conclusion

Understanding your right to refuse field sobriety tests in Colorado empowers you to make informed decisions when stopped by law enforcement. While refusal carries no criminal penalty, it’s important to understand both your rights and the practical implications of your choice.

Remember these key points:

• Field sobriety tests are voluntary in Colorado, you can refuse without criminal penalty
• FSTs are notoriously unreliable, with accuracy rates of only 65-77% under ideal conditions
• Refusing FSTs is different from refusing chemical tests after arrest
• Your refusal can be mentioned in court but creates no additional charges or penalties
• Many factors unrelated to intoxication can cause you to perform poorly on these tests

If you’ve been arrested for DUI in Colorado, whether you refused or performed field sobriety tests, contact Right Law Group immediately. We’re available 24/7 to protect your rights and begin building your defense.

Our experienced DUI defense attorneys serve clients throughout Colorado and are ready to fight for you. Contact us today for a free consultation.

Disclaimer: This article is provided for informational purposes only and does not constitute legal advice. The information contained herein is accurate to the best of our knowledge as of November 2025 but may not reflect the most current legal developments. Each case is unique, and outcomes depend on specific facts and circumstances. Laws and court procedures may vary by county and jurisdiction within Colorado. If you are facing criminal charges, consult with a qualified Colorado criminal defense attorney to discuss your specific situation.

Colorado Bar Advertising Disclaimer: The choice of a lawyer is an important decision and should not be based solely upon advertisements. Past results do not guarantee future outcomes. No attorney-client relationship is created by reading this article or contacting our firm for a consultation.