Stopped for DUI? Can You Refuse Field Sobriety Testing & Breath Testing?

In short, YES! 

In Montana, you can refuse any and all requested testing by law enforcement if stopped for DUI. 

By law, when driving and you come into contact with law enforcement, you must produce your:

  • Driver’s license
  • Registration
  • Proof of insurance

However, after that, law enforcement must have proper cause to suspect a person is under the influence of alcohol or drugs before they can ask them to perform any sobriety testing.

So, what will they ask you to do and what are your choices?


What happens after you’re stopped? 

Standard NHTSA protocol for any DUI investigation in the United States is exactly the same for every law enforcement agency.  Once your vehicle is stopped by law enforcement and they suspect you of a DUI, you will be asked to exit your vehicle.

The request to exit your vehicle is voluntary. You can refuse to do it. The downside of refusing this initial request is that you will likely be arrested for not cooperating and law enforcement will forcibly remove you – buy you can refuse to do it.

If you agree to exit the vehicle, law enforcement will traditionally request you perform at least 3 Standardized Field Sobriety Tests. These are psychophysical tests, meaning they test both your physical abilities and your mental capabilities simultaneously. 

Standardized Testing has some validated testing that correlates poor performance with alcohol intoxication. However, false positives due to other impairments like medicines and medical conditions are very possible as well.

3 Field Sobriety Tests

These are the field sobriety tests you usually see on TV. They are:

  1. Horizontal Gaze Nystagmus (HGN) – Commonly referred to as the “eye test”, where you follow an officer’s movement with your eyes.
  2. Walk and Turn  (WAT) – You’ll be asked to take a series of heel-to-toe steps on an imaginary line in a very particular way. 
  3. One Leg Stand (OLS)  – You’ll raise one foot for thirty seconds. 

Note: For more information about the specifics of these tests, please review our blog post on the Big 3 Standardized Field Sobriety Tests.


How accurate are field sobriety tests?

NHTSA studies showed that when performed correctly:

  • HGN, by itself, was 77% accurate
  • WAT, by itself, was 68% accurate
  • OLS, by itself, was 65% accurate

Not exactly a sure thing is it? And that’s assuming the officer was 100% accurate in how they both administered the test and evaluated the results.

What happens after a field sobriety test?

Standard protocol following the three Standardized Field Sobriety Tests is for an officer to request a breath or blood test. When you are outside by your car it is very common for this request to be a portable breath test. 

All of the above requests and testing may be refused to be performed. You don’t have to perform any psychophysical testing, and you don’t have to provide a breath test. 

You have an absolute right not to perform any Standardized Field Sobriety Tests, you don’t have to answer any questions and you don’t have to take any breath or blood test.

At this point, you’re probably saying to yourself, “I don’t have to do anything??” That’s right, you don’t have to do anything and law enforcement cannot force you to do any of these things – except one. 

Can an officer take your blood?

Law enforcement may be able to forcibly draw your blood, even if you refused a blood test, in some limited circumstances. The list of those circumstances can be found in another Judnich Law Office blog post. Other than that limited circumstance, law enforcement officers can’t force you to do anything in a DUI investigation.

You have the right to refuse any and all requests. 

Now, what penalty do you suffer for refusing to do anything?

The result of refusing to do any part of an officer’s request in a DUI investigation is certain: 

You will be arrested for DUI and you will likely suffer a suspension of your driver’s license for any refusal.

Think about it, if you are refusing to allow the officer to perform a DUI investigation and you exercise your right to refuse to do something, the officer will likely take that as cause to arrest, and simply arrest you for DUI.

That certainly does not mean they have the evidence to actually convict you of a DUI because you refused, but an arrest is usually imminent. An experienced DUI defense attorney can work wonders with an incomplete DUI investigation due to a refusal, so this should be carefully considered. 

Secondarily, any refusal will result in a suspension of your driver’s license. Under Montana statute 61-8-402 if you refuse to perform any testing requested by law enforcement in a DUI investigation, the officer must seize your driver’s license and suspend it for at least 6 months. The suspension length will be increased if you have previous refusals or DUI convictions on your record. 

So should you refuse?

Thus, there is a difficult choice to be made with serious consequences no matter what a suspect does in a DUI investigation. If you perform all testing and breath or blood tests requested, you may be providing law enforcement with all the evidence they need to convict you in a court of law for a DUI. 

Alternatively, you can refuse to do anything and not give law enforcement any evidence against you that can be used in court on a DUI charge, but the downside of refusing is that you will likely still be arrested and you will receive a 6-month (or longer) license suspension.

Speak with an experienced Montana DUI defense attorney

Navigating the complicated waters of DUI and DUI investigation should only be entrusted to an experienced attorney that focuses their practice on DUI. General “criminal attorneys” who take on every single type of case they can get just won’t have the specific DUI training and experience needed to obtain the best possible results in these types of complicated cases.

If you want to discuss your DUI case with an experienced DUI attorney at the Judnich Law Office, please call today for a free consultation. (406) 721-3354.