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Breathalyzer Tests & The Science: Are They Always Accurate?

Updated: May 25, 2023 @ 2:16 am

Reading Time: 4 Minutes

As a well-known Galveston DWI lawyer with a wealth of experience in criminal law, Tad Nelson is no stranger to challenging the veracity of breathalyzer tests in court. A number of our clients have asked us about the reliability of Breathalyzer testing and some don’t trust the devices at all.

Breathalyzers are tools used by law enforcement officers to gauge whether a driver is impaired by alcohol. Unfortunately, these devices are viewed as infallible pieces of technology by police officers and Sheriff’s deputies, but this certainly isn’t the case.

At The Law Offices of Tad Nelson & Associates, we’ve helped thousands of people to get their cases dismissed. If you need help, we would love to take a look at your situation.

Board Certified in Criminal Law

Tad Nelson is not only Board Certified® in Criminal Law by the Texas Board of Legal Specialization, but he’s also an ACS/CHAL Lawyer Scientist. Few attorneys in Texas, less so Galveston, are qualified to analyze said evidence and stage a formidable defense strategy.

If you’re facing prosecution in Galveston’s DWI court, put an experienced DWI defense attorney on your side. To get started, call us today at 409-904-0075.

Understanding How Breathalyzers Work

Breathalyzers are designed to measure the concentration of alcohol in your breath. The data collected by the device is used to estimate your blood alcohol concentration level (BAC).

When you consume an alcoholic beverage the alcohol is absorbed into your bloodstream through your stomach and small intestine. As your blood circulates the alcohol is carried to your lungs. Then, it vaporizes into the air you exhale. Breathalyzers measure the alcohol in your breath to determine your BAC.

Types of Breathalyzer Tests

There are different types of breathalyzer devices in use by law enforcement agencies here in Texas. Each of these devices has its strengths and weaknesses.

Let’s review a few of the most common types Breathalyzer devices used in Texas.

Semiconductor Oxide-Based Breathalyzers

These are the cheapest and most portable breathalyzer devices, typically used for personal use. They’re not as accurate as professional-grade equipment. Factors like temperature and humidity can affect their readings.

Fuel Cell Breathalyzers

These are more accurate and commonly used by law enforcement during field sobriety tests. However, fuel cell breathalyzers can sometimes confuse alcohol with other substances, leading to false positives.

Infrared Spectroscopy Breathalyzers

These are the most accurate Breathalyzer devices and are typically used at police stations for official BAC measurements. Yet, they’re expensive and not portable.

The Impact of External Factors on Breathalyzer Accuracy

Just because a breathalyzer test indicates that you’re over the legal limit doesn’t mean that you’re guilty of a DWI. External factors can often skew the results.

Health Conditions

Certain medical conditions can impact breathalyzer results. For instance, people with diabetes, hypoglycemia, or a high-protein diet may have acetone levels in their breath that can cause false positives in breath tests. Additionally, gastroesophageal reflux disease (GERD) can lead to alcohol from your stomach being present in your mouth which can lead to higher BAC readings.

Hygiene, Dietary, and Environmental Factors

Alcohol can also be detected as a result of using mouthwash or breath fresheners that contain alcohol as an active ingredient. Even some medications and food can potentially throw off a breathalyzer.

Environmental factors such as temperature and humidity can affect the results of these devices. If you live or work in Galveston, then you know it’s almost always humid.

Device Calibration

Breathalyzers must be calibrated regularly to ensure accuracy. If a device isn’t properly maintained, it can yield inaccurate results. We’ve had many DWI cases dismissed as a result of calibration issues with devices.

Calibration records are essential to verify the reliability of the test. As a knowledgeable Galveston County DWI attorney, I can help scrutinize these records to search for any discrepancies. If you have any questions, contact my office at 409-904-0075.

Fighting The Charge

Challenging Breathalyzer Tests

We can’t stress enough the fact that these tests aren’t always accurate. If you were arrested and charged with DWI and law enforcement is using the results of one of these devices as evidence, contact us.

It’s extremely important to have a DWI lawyer who knows how to challenge the validity of the test results when necessary.

For example, we may question the handling and maintenance of the breathalyzer, the training of the person who administered the test, or the impact of external factors like medical conditions. We may also study your case and incident location to uncover any environmental factors that may have impacted the results.

Remember, the results of a breathalyzer test are evidence in a DWI case, but it’s not the final word. You have the right to legal representation. You have the right to challenge the evidence against you. Use it.

Charged with DWI or DUI in Galveston?

Contact an Experienced DWI Lawyer Today!

Navigating the complexities of DWI law requires expertise and experience. Tad Nelson, Board Certified® in Criminal Law by the Texas Board of Legal Specialization, has been practicing law in Texas since 1991. With a strong presence in Harris County & Galveston County, Tad Nelson & Associates is a leading force in DWI defense in Greater Houston and throughout Texas.

Challenging the accuracy of a breathalyzer test is no easy task, but with our seasoned attorneys in your corner, you stand a fighting chance. Whether it’s a first-time DWI charge or you’re facing subsequent charges, you’ll benefit significantly by having skilled legal representation.

At the Law Offices of Tad Nelson & Associates, we’re committed to providing robust defense strategies tailored to your unique case. By scrutinizing every piece of evidence, including breathalyzer test results, we might find a way to get your case dismissed.

If you’re facing a DWI charge in Galveston County and need a dedicated, experienced, and strategic advocate on your side, contact us today at 409-904-0075.

Breathalyzer Tests & The Science: Are They Always Accurate?

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Breathalyzer Tests & The Science: Are They Always Accurate?
Breathalyzer Tests & The Science: Are They Always Accurate?
Breathalyzer Tests & The Science: Are They Always Accurate?
Breathalyzer Tests & The Science: Are They Always Accurate?
Breathalyzer Tests & The Science: Are They Always Accurate?
Breathalyzer Tests & The Science: Are They Always Accurate?