Breathalyzer in Nevada DUI cases – Can I fight it in court?

If you are arrested for drunk driving in Nevada, the state’s “implied consent” law requires you to take an evidentiary breath test (EBT) or blood test to measure your blood alcohol content (BAC). Driving with a BAC of 0.08% or higher is an automatic DUI, even if you were not impaired.

Here are four key things to know:

False BAC results can be caused by certain medical conditions or by the breathalyzer being defective or mishandled.
If the police suspect you ingested drugs, you must take the blood test because breathalyzers detect only alcohol.
If you refuse to take the EBT or blood test, you will be subject to a one-year driver’s license revocation and a forced blood draw.
You can contest your license suspension at a DMV hearing.

In this article, our Las Vegas drunk driving attorneys will address the following key issues regarding DUI breath tests in Nevada:

1. Challenging Results

Depending on the facts of your case, we will explore the following defenses when fighting your Nevada DUI charge:

Defenses
Procedural defenses	The breathalyzer or its aqueous solution was not calibrated, inspected, or maintained properly. The officer or breath test technician did not have proper training or was not certified. The officer administered the test outside of the two-hour post-arrest window. The officer did not perform a 15-minute observation period prior to giving the test. The breath test was not administered two times right after each other, or the two BAC readings differ by more than 0.02%.
Environmental or mechanical defenses	Radio frequency interference (RFI) caused the breathalyzer to skew the BAC results. The breathalyzer was broken.
Physiological defenses	You suffer from GERD, heartburn, diabetes, or acid reflux, which can “fool the machine” and cause a falsely high BAC reading. You had mouth alcohol (such as from mouthwash), which masked your deep lung air (alveolar air) that breathalyzers are meant to measure. You were on an Atkins-style low carb/ high protein diet, which auto-produces isopropyl alcohol. This can “trick” the breathalyzer into showing a high BAC.

If we can cast doubt on the accuracy of the breath test, then the court might exclude it as evidence. Once the BAC results are excluded, the prosecution should be more willing

to reduce the drunk driving charge to reckless driving or
to throw it out completely.¹

2. DUI Charges with No Breath Test

You can be charged with DUI in Nevada based on blood test results rather than breath test results.

Even if the blood results show a legal BAC level, you could still be convicted if you were impaired. However, it is much harder for prosecutors to prove DUI without a failing breath- or blood test.

3. Refusing the Breath Test

Under Nevada law, you give “implied consent” to submit to an EBT (or blood test) after you are arrested for DUI. Nevada law imposes various consequences for refusing to take an EBT (or blood test):

The police must get a telephonic warrant to administer an evidentiary blood test. Then the officer may use “reasonable force” to accomplish the blood draw.
The DMV will revoke your driving privileges for one year. (The revocation period increases to three years if you already had a license revocation in the previous seven years for refusing to take an evidentiary test.) The DMV will impose this revocation even if you ultimately pass the blood test and the DUI charge gets dismissed.
If the case goes to trial, the prosecution may introduce as evidence that you refused the EBT.

Some DUI suspects make a good faith effort to provide a lung sample but cannot sustain an exhale forceful enough or long enough for the breathalyzer to operate. When this happens, police call it a:

machine refusal or
technical refusal.

Despite what the police say, your inability to provide an adequate lung sample is not an indication of guilt. Therefore, should your case go to trial, we would ask the court to suppress as evidence any mention the police made that you refused.²

4. Driver’s License Consequences

Getting your license revoked is a standard DUI penalty in Nevada no matter whether you take the breath or blood test:

A DUI first triggers a 185-day license revocation.
A DUI second triggers a 1-year license revocation.
A DUI third triggers a 3-year license revocation.

Note it may be possible to continue driving during the revocation period with an ignition interlock device in your vehicle.

(Remember from section 3 that refusing to take a breath- or blood test triggers a one-year license suspension even if your DUI case is dropped.)

Contesting your License Revocation

If you take a breath test following your DUI arrest – or if you refuse to take a test at all – the police will give you a temporary license good for seven days. In order to contest the license suspension at a DMV hearing, we must request the hearing within those seven days.

Once we request the hearing, you can continue driving on the temporary license until the DMV hearing occurs (which will likely be a month down the line). If the seven days pass without requesting a hearing, the year-long license suspension will begin on the eighth day.

DMV hearings are like mini-trials held at a DMV administrative office, and they are difficult to win because the state’s burden of proof is so low. Still, a DMV hearing is worth doing because it serves as a valuable dry-run for your criminal case (which is completely separate and independent from the DMV case).³

5. Preliminary Breath Tests v. Evidentiary Breath Tests

When you are initially pulled over for a traffic stop, the police will ask you to take a preliminary breath test (PBT) to help them determine whether you may be under the influence. Here are the differences between PBTs and EBTs:

NEVADA DUI LAW	Preliminary Breath Test	Evidentiary Breath Test
When is it administered?	When police have reasonable suspicion you may be intoxicated	After you have been arrested for DUI
Is it mandatory?	Yes	Yes, unless you take a blood test instead
Can results be used in court to show I was intoxicated?	No	Yes
What if I refuse?	Police will arrest you for DUI if “reasonable grounds” exist.	You lose your license for one year, even if your DUI charge gets dismissed

6. Evidentiary Blood Tests v. Evidentiary Breath Tests

The following chart compares evidentiary breath tests and blood tests in Nevada DUI cases.

	DUI Blood Tests	DUI Breath Tests
Accuracy	Generally more accurate	Less accurate, can be affected by acid reflux, GERD, mouth alcohol, and more
Invasiveness	Invasive, requires blood draw	Non-invasive, requires breathing into a device
Time to results	Longer, typically weeks	Immediate results
Administration	Requires medical professional	Can be administered by law enforcement
How it measures alcohol	Direct measurement of blood alcohol content (BAC)	Estimates BAC based on breath alcohol content
Detects drugs?	Yes	No
Retention of sample	Sample can be retained for future testing	No sample retention
Refusal consequences	Driver’s license suspension	Driver’s license suspension

police officer administering a breath test to a DUI suspect - these are required in certain Las Vegas DUI investigations — Nevada police use the Intoxilyzer 8000 to administer EBTs.

Frequently Asked Questions

What is the legal blood alcohol limit in Nevada?

The legal blood alcohol concentration (BAC) limit in Nevada is 0.08% for standard drivers aged 21 and older. For commercial vehicle drivers, the limit is 0.04%, and for drivers under the age of 21, Nevada has a strict limit of 0.02%.

Do I have to take a roadside breathalyzer test in Nevada?

When pulled over, an officer may ask you to take a Preliminary Breath Test (PBT) by the side of the road. You can legally refuse this roadside test without facing an automatic license suspension, though the officer may still arrest you if they have other probable cause. However, once arrested, you are required by law to take an official evidentiary test.

What happens if I refuse a breath test after a DUI arrest in Nevada?

Under Nevada’s “implied consent” law, refusing to take an Evidentiary Breath Test (EBT) or blood test after being arrested for a DUI will result in an automatic one-year revocation of your driver’s license. Additionally, the police can obtain a telephonic warrant to forcibly draw your blood for testing.

Is it better to choose a breath test or a blood test in Nevada?

Both have pros and cons. A breath test is less invasive and gives immediate results, but it can be less accurate and susceptible to outside factors. A blood test is generally more accurate and the sample can be saved for independent re-testing later. Note: If the police suspect you are under the influence of drugs, you do not get a choice; you must take a blood test.

Can a breathalyzer test be wrong?

Yes. Breathalyzer machines like the Intoxilyzer 8000 used in Nevada can produce false readings. Results can be skewed by improper machine calibration, a lack of operator training, radio frequency interference, or the suspect’s medical conditions such as GERD, acid reflux, or even certain high-protein diets.

Can I get a DUI in Nevada if I passed the breath test?

Yes. Even if your BAC is below the 0.08% legal limit, you can still be charged and convicted of a DUI if the prosecution can prove that your ability to drive safely was impaired by alcohol or drugs.

How long do I have to fight my license suspension after a DUI breath test?

If you fail or refuse an evidentiary breath or blood test, the police will confiscate your physical license and issue you a temporary one. You only have seven (7) days to request an administrative hearing with the Nevada DMV to contest your license suspension.

Additional Reading

For more information about Nevada DUI laws, refer to our related articles:

Nevada DUI: Should I choose a breath test or a blood test? – a side-by-side comparison of the pros and cons of each chemical test
The court process in Nevada DUI cases – a step-by-step look at how drunk/drugged driving cases proceed through criminal court
Top 20 defenses to a Las Vegas Nevada DUI charge – overview of the most common ways to fight DUI charges
I was suffering from hypoglycemia when I was arrested for DUI in Nevada. Can I use this to fight the charges? – a deep dive into how diabetes can affect breath test results
Do I have to admit that I’ve been drinking if I’m pulled over for DUI in Nevada? – a discussion of how you should be polite to police but not answer any questions

Legal References

NAC 484C.100–.120; NRS 484C.200. See also State v. Sample (Nev. 2018) 414 P.3d 814.
NRS 484C.150; NRS 484C.160; NRS 484C.240. NRS 484C.160. If you are arrested for drunk driving in Nevada, you can usually elect to take a blood test instead of a breath test. Since taking blood samples is a more complicated procedure than using a breathalyzer, you must pay for all associated costs if a working breathalyzer was readily available, and you are ultimately convicted of DUI. Note that if police believe you are under the influence of drugs, you must take a chemical test for blood because breathalyzers cannot detect drugs. Then if your results come back positive for DUI, the Nevada Department of Motor Vehicles will mail you a letter notifying you that they will revoke your license. Note that you can elect to have your blood independently taken and tested at your own expense. NRS 484C.180. See also Byars v. State (Nev. 2014) 336 P.3d 939.
NRS 484C.220. NRS 484C.210. Note that if you voluntarily choose to take the blood test rather than the breath test following your DUI arrest, the police will not confiscate your license right away because it will take several weeks to get your blood results back. Instead, you can continue driving on your license until if/when the DMV mails you a notice of revocation and a seven-day temporary license. At that point, you must request a DMV hearing before the temporary license expires if you wish to contest your license revocation.