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

Breath tests in Nevada DUI cases measure whether an alleged drunk driver has an illegal blood alcohol content (BAC) of 0.08% or higher.

First, you take a preliminary breath test (PBT) at the scene of the alleged DUI. If you fail the PBT and get arrested, you must then take an evidentiary

• breath test or
• blood test.

Only the evidentiary test results – and not the PBT results – are admissible as evidence at trial.

Refusing to take the breath test

Refusing to take the PBT will usually result in the police officer confiscating your driver’s license and arresting you for a DUI offense.

If you refuse to take the evidentiary breath test, you face a 1-year driver’s license revocation and can be forced to submit to an evidentiary blood test.

Defenses against breathalyzer results

Some common arguments to challenge breath test results in court are:

• The Intoxilyzer 8000 breath testing machine was defective,
• You had a medical condition that caused the device to return an inflated BAC result, and/or
• The police made a procedural error while handling the device

A skilled Nevada criminal defense attorney may be able to get the breath test results excluded from evidence.

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. Am I required to take 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?

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 breathalyzers on people suspected of having driven under the influence of alcohol. Driving with a BAC of .08 or higher is per se illegal.¹

Breathalyzers usually employ infrared spectroscopy and/or fuel cell technology. The devices convert the quantity of alcohol in your breath to the quantity in your blood. This conversion often causes compromised results and inaccurate readings.

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.

Also unlike blood tests, breathalyzers cannot detect drugs — only alcohol.

1.1. How the breathalyzer works

The type of breathalyzer Las Vegas police use on DUI arrestees is the Intoxilyzer 8000. It is manufactured by CMI, Inc., in Owensboro, Kentucky. It was approved for use in Nevada by the Nevada Committee for Testing on Intoxication.

The Intoxilyzer 8000 uses a two-filter wheel infrared (IR) spectrometer to detect organic vapors in a breath sample. Although it takes about 20 minutes to warm up, the device has a “standby” mode that permits it to run continuously without depleting its resources.

Unlike previous models which had a pressure switch, the Intoxilyzer 8000 uses a flow sensor. In order for the flow sensor to work, the following four conditions must be met:

1. You blow no less than 1.1 liters of air into the tube;
2. You blow continuously for no less than one (1) second;
3. The alcohol concentration slope starts to plateau;
4. The pressure reaches about 50 psi.

Finally, the blood alcohol level results get printed on paper.²

Note that Intoxilyzer breath testing machines are typically kept at police stations or detention facilities. Though police can bring traveling units to the scene of a suspected DUI.

1.1.1. Technical info

The machine uses the “Dry Gas Standard” to conduct control tests during the breath test sequence. The correct gas concentration is 0.08 g/210L with an acceptable range from 0.075 to 0.085  g/210L.

When any analysis result falls outside of the acceptable range, the machine displays CONTROL OUTSIDE TOLERANCE.³

This is the checklist that Nevada police must complete when administering an evidentiary breath test if you are arrested for DUI of alcohol.

2. What is the difference between preliminary breath tests and evidentiary breath tests in Nevada DUI cases?

If you are suspected of drunk driving in Las Vegas, you may be asked to take two separate breath tests:

1. A preliminary breath test (PBT) takes place on the road shortly after you are pulled over, and
2. an 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.

If you are suspected of DUI in Nevada, you are legally required to submit to a PBT. When you refuse to submit to a PBT, the police will

• confiscate your license and
• arrest you for DUI.

Note that if the police arrest you prior to giving the PBT, the police may not then give you a PBT without your consent to take it or without a warrant (or valid warrant exception). Otherwise, the PBT may qualify as an unlawful police search.⁴

2.2. Evidentiary Breath Test (EBT)

Under Nevada’s implied consent law, motorists arrested for DUI are legally required to submit to an evidentiary

• breath test (EBT) or
• blood test.

(If the police believe you are high instead of drunk, you must submit to a blood test.)

Similar to Title 17 in California, Nevada law outlines strict rules that police must follow when administering an evidentiary breath test and analyzing the results. The regulations include the following:

• No more than two (2) 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 fifteen (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 (2) times right after each other, and the two BAC readings cannot differ by more than .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 .08 or above.⁶

3. Am I required to take breath tests in Nevada DUI cases?

Legally, yes, and there are dire consequences for refusing.

If you are suspected of driving under the influence in Nevada, you are considered to have given “implied consent” to take a preliminary breath test. If you get arrested for DUI, you are considered to have given “implied consent” to take an evidentiary

• breath or
• blood test.

Note that you are expected to submit to an evidentiary blood test if the police suspect you of driving while impaired by drugs. This is because breathalyzers cannot detect controlled substances.

Nevada law imposes various consequences for refusing to take a preliminary or evidentiary breath test: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 (1) year. (The revocation period increases to three (3) years if you already had a license revocation in the previous seven (7) 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.

3.1. Blood tests

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:

1.  a working breathalyzer was readily available, and
2.  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 instead of a breath test. 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.⁸

4. How accurate are the breathalyzers that Las Vegas police use?

Not very accurate considering so many variables unrelated to alcohol can cause false positives. (Scroll down to the next section for a list of some of these variables.)

One problem stems from the manufacturer’s refusal to share the Intoxilyzer 8000’s source code. The manufacturer claims it is a trade secret, but hiding the source code precludes researchers from running comprehensive tests on the machine’s efficacy. Just in the last few years, judges in

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

have ruled that the Intoxilyzer 8000 cannot be trusted.⁹

That is why it is vital you retain a drunk driving defense attorney to uncover any and all evidence suggesting that the breathalyzer was

• defective,
• unreliable or
• mishandled in your Nevada DUI case.

5. How can breathalyzer results be challenged in Nevada courts?

Depending on the facts of your case, a criminal defense lawyer may explore the following procedural, environmental, or physiological defenses when fighting a DUI charge:

Ways to challenge breathalyzer results in Nevada DUI cases	Possible strategies
Procedural defenses	The breathalyzer device or aqueous solution inside was not calibrated, inspected, or maintained properly. The officer or breath test technician who administered the breathalyzer did not have proper training or was not certified. The officer administered the test outside of the two (2) hour post-arrest window. The officer did not observe the fifteen (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 or otherwise non-functional.
Physiological defenses	You suffer from such conditions as GERD, heartburn, diabetes, or acid reflux. These conditions can “fool the machine” and cause a falsely high BAC reading. You had alcohol in your mouth (“mouth alcohol”), which masked the deep lung air (alveolar air) that Nevada breathalyzers are meant to measure. Even mouthwash can cause a false positive result. You experienced rising blood alcohol, which caused the breathalyzer to register a higher BAC than you actually had while driving. You were on an Atkins-style low carb/ high protein diet at the time, which auto-produces isopropyl alcohol. This can “trick” the breathalyzer into showing a high BAC even if you had little or nothing to drink.

Therefore, numerous factors can cause a breathalyzer to give falsely high readings. Consequently, you should tell your DUI defense lawyer everything you can remember regarding the DUI incident:

• Medical history,
• diet,
• health,
• even what you ate or drank that day.

Something that seems irrelevant may be the key to fighting the charge.

If a criminal defense attorney can cast doubt on the accuracy of the forensic 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.

We are here to help

A DUI arrest is not a DUI conviction. If you have been arrested for DUI in Nevada, you are invited to contact our Las Vegas criminal defense attorneys for a phone consultation.

Whether you took a breath, blood or urine test, our DUI defense attorneys are skilled in all the ways to try to exclude the results from evidence so your DUI charge may get reduced or dismissed completely. We serve clients in Las Vegas, Henderson, Reno, and throughout the state of Nevada.

Arrested in California? Go to our article on DUI breath tests in California.

Arrested in Colorado? Go to our article on DUI breath tests in Colorado.

---

Legal References