Breathalyzer in Nevada DUI case – 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 five key things to know:

1. When police first pull you over on suspicion of DUI, they will ask you to take a preliminary breath test (PBT).
2. The PBT results cannot come in as evidence at trial; police just use it to determine whether there is probable cause to arrest you.
3. Refusing to take the PBT will result in the police officer confiscating your license and arresting you for DUI.
4. If you refuse to take the EBT or blood test after your arrest, you face a 1-year driver’s license revocation and a forced blood draw.
5. Potential defense to DUI charges are 1) the breathalyzer was defective, 2) your medical condition caused a false BAC result, or 3) the police mishandled the device.

In this article, our Las Vegas DUI attorneys discuss:

• 1. What are breathalyzers in Nevada DUI cases?
• 2. What is the difference between preliminary and evidentiary breath tests?
• 3. What if I refuse the breath tests?
• 4. How accurate are breath tests?
• 5. How can the results be challenged in court?
• 6. Can I be charged with DUI with no breathalyzer?
• Additional resources

1. What are breathalyzers in Nevada DUI cases?

Breathalyzers are mechanical devices that measure your blood alcohol concentration (BAC) through your breath. Police agencies such as the Nevada Highway Patrol and Las Vegas Metropolitan Police use them on drivers they suspect have an illegal BAC of 0.08% or higher.¹

Unlike DUI blood tests, breath tests are largely painless and non-invasive: You blow into the breathalyzer, which then uses an internal aqueous solution of ethanol to analyze the breath and estimate your BAC.

The breath testing machine that Las Vegas police use on DUI arrestees is the Intoxilyzer 8000.² This is the checklist that Nevada police must complete when administering it.³

2. What is the difference between preliminary and evidentiary breath tests?

The preliminary breath test (PBT) takes place on the road shortly after you are pulled over. The evidentiary breath test (EBT) takes place at the police booking station following your arrest. Each test is different and serves a distinct purpose:

2.1. Preliminary Breath Test (PBT)

When you are pulled over in Nevada – or when the police arrive at the scene of an accident where DUI is suspected – the police will probably ask you to do three things:

1. take out your driver’s license and registration,
2. perform field sobriety tests, and
3. submit to a preliminary breath test (PBT).

The PBT is also called a roadside breath test or preliminary alcohol screening (PAS). It is meant to give the police officer an initial idea of whether you are under the influence of alcohol or not.

If the case goes to trial, PBT results may come in as evidence to show the police had “reasonable grounds” for arrest. Though PBT results cannot be used to show that you were driving under the influence.⁴

2.2. Evidentiary Breath Test (EBT)

Nevada law outlines strict rules that police must follow when administering an evidentiary breath test following your arrest. These regulations include the following:

• No more than two hours can elapse between the time of driving the motor vehicle and the breathalyzer test.
• The officer is required to observe you for at least 15 minutes prior to administering the breathalyzer test. This is to make sure you do not vomit, burp, belch, regurgitate or do anything else that can skew the breath results.
• The breath test must be administered two times right after each other, and the two BAC readings cannot differ by more than 0.02%.
• The breathalyzer needs to have been properly maintained and calibrated.
• The police officer needs to be certified to administer the breathalyzer.⁵

Unlike PBT results, EBT results can be used against you in court to show that your BAC was 0.08% or above.⁶

3. What if I refuse the breath tests?

Under Nevada law, you give “implied consent” to:

• submit to a PBT if you are suspected of DUI during a traffic stop; and
• submit to an EBT (or blood test) after you are arrested for DUI.

Nevada law imposes various consequences for refusing to take a PBT or EBT:⁷

Type of Breath Test	Consequences for refusing to take a breath test
Preliminary breath test (PBT)	The officer confiscates your driver’s license. The officer will arrest you. If the case goes to trial, the prosecutor may introduce as evidence that you refused the PBT.
Evidentiary breath test (EBT)	The police must get a 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.8

4. How accurate are breath tests?

Not very accurate considering so many variables unrelated to alcohol can cause false positives.

One problem stems from the manufacturer’s refusal to share the Intoxilyzer 8000’s source code. Just in the last few years, judges in

• Florida,
• Oklahoma, and
• even Ontario, Canada

have ruled that the Intoxilyzer 8000 cannot be trusted.⁹

5. How can the results be challenged in court?

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

Ways to challenge breathalyzer results in Nevada DUI cases	Possible strategies
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 the 15-minute observation period prior to giving the test.
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.

6. Can I be charged with DUI with no breathalyzer?

Yes, you can be charged with DUI in Nevada based only on blood 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.

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-drive 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