DUI Breath Tests

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DUI Breath Tests In Las Vegas

DUI breath tests are the most widely used types of evidence used in DUI cases. As a result, they are essential to prosecutors when pursuing DUI convictions in Las Vegas. If a breathalyzer device shows your blood alcohol concentration (BAC) is above .08, you’ll be arrested.

While failing a breath test may seem like a “shut and closed” case, that’s not always true. Sometimes, breath tests are inaccurate for a myriad of reasons such as a police error, device malfunction, residual mouth alcohol, medical conditions, etc.

If you’ve recently failed a DUI breath test, it doesn’t guarantee that you’ll be convicted. It can certainly make it more challenging to have your charges dismissed or decreased, but not impossible. An experienced Las Vegas DUI lawyer will advocate for your rights, negotiate with the prosecution, and push for dropped or reduced charges where possible.

At The Vegas Lawyers, our lawyers and paralegals are compassionate, savvy, and experienced. We know what we’re doing and can help you receive the least amount of penalties possible when charged with a DUI. We handle DUI cases in Las Vegas, Henderson, North Las Vegas, Boulder City, Searchlight, Mesquite, Laughlin, Goodsprings, and Pahrump.

When Are DUI Breath Tests Administered?

The Las Vegas Metropolitan Police Department, the Nevada Highway Patrol or a similar law enforcement agency in Nevada can administer a DUI breath test in two situations. Tests are administered at the time of a DUI traffic stop as a preliminary alcohol screening (PAS).  DUI breath tests can also be administered post-arrest to serve as an evidentiary screening. Learn more about each below.

Before An Arrest – Preliminary Breath Test (PBT)

The PBT is administered before a police officer knows if you’re under the influence or not. At the time of giving the preliminary breath test, you are not under arrest. It is typically administered with a portable breath test device. It’s important to note that PBT DUI breath tests are a type of field sobriety test, so most drivers can decline to take it.

However, if the driver suspected of DUI is on DUI probation or under 21, they are required to take the test or face a 1 – 3-year license suspension.

After An Arrest – Evidentiary Breath Test

Regardless of whether you’ve taken a preliminary breath test, Nevada police will require you to take a post-arrest evidentiary breath test if you’re arrested.  If you’re arrested for DUI, a blood test, breath test, or urine test is mandatory. In most cases, police officers give you the option to take a breath test or blood test.

Depending on the circumstances, breath tests are usually the best option. However, a blood test may be required in certain situations. This is especially true if you are suspected of driving under the influence of drugs (DUID), can’t blow into the device hard enough, or unconscious at the time of the arrest.

Can I Refuse To Take a DUI Breath Test?

As mentioned above, you can refuse a preliminary breath test without consequences in most cases. However, if you’re under arrest, an evidentiary breath test refusal can lead to serious consequences, even if you’re not convicted of a DUI. Consequences of refusal can include:

  • Mandatory 1 – 3-year license suspension
  • Jail time if convicted

A refusal of a post-arrest breath test is only permissible if you opt to take a blood test instead. However, you should be aware of the differences between the two tests. Blood tests are typically more accurate and harder to defend in court in most instances.

Should I Choose To Take a Blood Test Instead?

Nevada DUI lawyers have not come to a universal consensus about which is better to take. At the end of the day, it depends on the unique circumstances of your arrest. Generally, each option has its benefits and drawbacks. For instance, a breath test is less accurate and easier to defend, but it’s usually administered on the spot.

On the other hand, you typically have more time to take a DUI blood test, so your blood alcohol concentration levels may drop (or, in some cases, increase) before you take the test. Blood test results are also saved, so your DUI lawyer can motion to have your samples independently tested by requesting a “blood split” motion.

How Do Breath Tests Work?

Breath test devices typically work in one of three ways to determine a person’s BAC levels. They include a semiconductor oxide sensor, infrared spectrometer, or a fuel cell sensor. Learn more about each below.

  • Semiconductor Oxide Sensors: Law enforcement officers do not typically use this type of breath test. It is better suited for personal or low-volume use at home. They work by using a chemical reaction involving alcohol, which produces a color change based on a person’s BAC.
  • Fuel Cell Testers: More than 30 states use fuel cell testers for roadside breath tests. They are very accurate. These devices measure blood alcohol concentration levels by creating a chemical reaction that oxidizes any alcohol in the breath sample to produce an electrical charge. The higher the electrical charge, the higher a person’s BAC is presumed to be.
  • Infrared Spectrometer: Las Vegas police are more likely to use the “Intoxilyzer 5000EN,” an infrared spectrometer. They work by detecting molecules in the breath sample based on how they absorb infrared light. You can find them at the police station in many cases, but many have also been developed for roadside testing.

The Nevada Committee on Testing for Intoxication has approved many types of breath testing devices for use in evidential and preliminary tests. Each device has its pros and cons. A skilled DUI lawyer will understand what kind of test you were given and its limitations.

Breath tests are designed to measure the amount of alcohol present within a person’s “alveolar” air, essentially the air coming from your deep lungs. They don’t measure a person’s actual BAC, but rather their partition ratio.

The partition ratio compares the amount of alcohol present in the breath to the amount in the blood. Nevada law stipulates the partition ratio should be 2,100: 1. However, the rate of alcohol absorption in the lungs varies person-to-person. The science of differing partition ratios can help defendants to fight DUI charges in some circumstances.

Are Breath Tests Accurate?

Breath tests make assumptions about the average BAC levels of an intoxicated person and base its reading on that assumed level. Years of research have concluded that breath test results can be 15 percent higher or lower than a person’s actual BAC levels.

It has been shown that nearly 23 percent of people tested via a breath test will have a higher reading than their real BAC levels. So, one out of every four readings is potentially false. That’s not including the high chance of a police officer using the device improperly or not following the correct protocols prescribed by Nevada DUI laws.

With this in mind, it can be challenging for an individual to determine if their breath test results are inaccurate without the help of an experienced DUI lawyer.

What is Residual Mouth Alcohol?

Speaking of inaccurate readings, many breath test results are rendered invalid due to residual mouth alcohol. Residual mouth alcohol is the remnants of alcohol left in a person’s mouth after drinking, using mouthwash, cough syrup, or alcohol-infused breath fresheners. Residual mouth alcohol can easily contaminate breath test results if the test is not administered correctly.

How Long After Using Mouthwash Can You Fail a Breathalyzer?

Generally, residual mouth alcohol dissolves in about 15 minutes. The alcohol in your mouth reduces by 75 percent within the first two minutes after use and about 50 percent more every two minutes after.

This is why police officers are typically required to wait and observe suspects at least 15 minutes before administering a breath test. If they don’t, a DUI attorney could push to have your charges decreased or dismissed.

What Medical Conditions Can Lead to False Readings?

Suppose you’re pulled over and placed under arrest for a DUI. In that case, it’s essential to notify the arresting officer of any potential medical conditions that could lead to a false breath test reading. Certain medical conditions and eating habits can lead to inaccurate results. They can include:

  • High protein and low carb diets
  • Diabetes
  • Gastrointestinal reflux disease (GERD)

A skilled Las Vegas DUI lawyer will know if your medical condition or diet could be a potential DUI defense. It could be the key to clearing your name and having your charges dismissed or decreased.

What Are The Consequences of Getting a DUI in Nevada?

Specific consequences for a DUI conviction in Nevada vary depending on the circumstances of your case, your BAC levels at the time of arrest, and if you caused an accident or fatality as a result of being under the influence. In general, you can expect the following consequences if convicted of a DUI in Las Vegas.

  • First DUI (Within 7 Years): Misdemeanor, 48 hours – 6 months jail time, $400 – $1000 in fines, DUI school, Victim Impact Panel, up to 185-day license suspension, potential installation of an ignition interlock device.
  • Second DUI (Within 7 Years): Misdemeanor, 10 days – 6 months jail time, fines between $750 – $1000, Victim Impact Panel, alcohol dependency evaluation, 185-day mandatory installation of an ignition interlock device, 1-year license suspension.
  • Third DUI (Within 7 Years): Felony offense, 1 – 6 years jail time, fines between $2,000 – $5,000, Victim impact panel, alcohol/drug dependency evaluation, mandatory installation of ignition interlock device (1 – 3 years), 3-year license suspension.

Penalties for a DUI causing injuries or fatalities can be more severe, including up to 20 years in jail. At The Vegas Lawyers, we understand the potential devastation DUI penalties can cause in your life. Our DUI lawyers work to ensure you receive the least amount of penalties possible under the conditions of your arrest.

Potential Defenses to a Failed DUI Breath Test

Being charged with a DUI doesn’t mean that you’ll be convicted. Even if you fail a DUI breath test, there are potential defenses that your DUI attorney can deploy to have your charges decreased or dismissed. Some of the most common defenses to failed DUI breath tests include:

  • A defective breath test device
  • Procedural errors committed by the police officer
  • Lack of appropriate device maintenance and calibration
  • Neglecting to adhere to the 15-minute observation time before testing
  • Lack of appropriate training
  • Medical conditions

A reputable criminal defense DUI lawyer can potentially get your breath test results excluded from evidence. It’s important to seek legal counsel as soon as you can after your arrest. The more information and time your attorney has to work on the case, the better.


Contact The Vegas Lawyers Today

If you’ve been charged with a DUI in Las Vegas or Southern Nevada, The Vegas Lawyers are here to mount a 5-star defense on your behalf. We are considered a top DUI law firm because we only work with the best lawyers and paralegals. We handle DUI cases all over southern Nevada, including:

  • Las Vegas
  • Henderson
  • North Las Vegas
  • Boulder City
  • Searchlight
  • Goodsprings
  • Pahrump

We know what it takes to mount a successful DUI defense. Don’t gamble with your future. Contact The Vegas Lawyers or give us a call at (702) 707 – 7000 today to schedule your free initial consultation.

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