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DWI Breathalyzer Test

Breathalyzers are a device used by law enforcement to calculate a person’s blood alcohol concentration (BAC). They can either be portable (known as a Portable Breath Test or PBT) or full-sized, which are usually located at the law enforcement station. Law enforcement famously use these instruments to determine if a driver is under the influence of alcohol or drugs. While the test is technically based in science, it comes with a lot of flaws.

Breathalyzers use very sensitive specialized reactive mixtures to determine a blood alcohol concentration. The sensitivity of these chemicals means they can easily react to other outside or internal factors and therefore skew BAC readings. Very simple outside factors could lead to false breathalyzer’s results including having acid reflux or taking cold medicine and driving.

These instruments are very fragile as well. They must be calibrated correctly and maintained regularly to ensure they don’t malfunction. Many unlucky people have been arrested for DWI due to poorly maintained breathalyzers, both portable and full-sized. Due to these factors and more, it’s important you always challenge BAC readings if you’ve been charged with DWI.

Brownsville DWI Attorney for Breathalyzer Tests

Information collected from a breathalyzer test can be used against you in trial. That’s why it’s incredibly important you hire an experienced Cameron County DWI defense lawyer as soon as possible. You can find that attorney today with the legal team at The Gracia Law Firm, P.C. Our experienced DUI lawyers have challenged countless breathalyzer, blood, and urine results in court successfully.

Call The Gracia Law Firm, P.C. at 956-504-2211 to set up your first consultation with us free of charge. The Gracia Law Firm, P.C. accepts clients in the greater Cameron County and Willacy County area including Brownsville, Harlingen, Olmito, Los Fresnos, Port Isabel, Palm Valley, San Benito, La Feria, Raymondville, San Perlita, and Lyford. We also represent clients in the Hidalgo County, Texas area.

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What is a Breathalyzer Test?

A breathalyzer or intoxilyzer test is an instrument designed to determine a person’s blood alcohol concentration (BAC). The device is made of two glass vials consisting of a mixture of chemicals as well as a system of photocells connected to a meter. That meter is there to calculate changes that may occur in the chemical mixture due to a reaction.

Breathalyzers calculate BAC by having a person enter a breath sample. The sample is then processed through a mixture of chemicals. This mixture includes dichromate, sulfuric acid, silver nitrate, potassium, and water. If the chemical mixture turns from a reddish orange to a green, then the breath sample must contain some ethanol. Since ethanol is a component of alcohol, this is a red flag to law enforcement the person who gave the sample is intoxicated.

Officers will then compare the tested reacted mixture with an unreacted control mixture. From this comparison, officers can deduce a blood-alcohol concentration (BAC) reading.


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Do You Have to Take a Breathalyzer Test in Texas?

Technically no. You don’t have to take a breathalyzer test if a law enforcement asked you to. However, it’s important to understand that refusing a breathalyzer test does come with some consequences. Denying a breathalyzer test is considered a violation of implied consent laws and will therefore result in an administrative penalty.

Implied consent laws essentially state if a person uses Texas public roads or freeways, they are also implicitly giving consent to a chemical DWI test. Despite this, you can still refuse a breathalyzer test. Just know if you do you will face an administrative penalty. It’s also important to remember that law enforcement don’t have to have BAC results to arrest you. If officers have reasonable suspicion your physical and mental faculties have been significantly influenced by an intoxicating substance and you’re unable to drive because of it, they can still arrest you.


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Can You Refuse a Breathalyzer Test?

Despite implied consent laws, you can still refuse a breathalyzer test by law enforcement. Just know you will face an administrative penalty for doing so. If you refuse a breathalyzer test, then your license will be automatically suspended for up to 180 days. If it’s your second refusal, you could face a license suspension for up to two years.

Failing a breathalyzer test will also yield an administrative penalty as well as criminal charges. The first failed breathalyzer test will result in an administrative suspension for up to 90 days. If you’ve been previously suspended for failing or refusing a breathalyzer, then the suspension term will be enhanced to one year.

Breathalyzers and other similar devices aren’t fool-proof machines and are known to sometimes yield false results. That is why most Texas DUI defense lawyers will advise you to not submit to a breathalyzer test if law enforcement requests one. The test could produce a false BAC reading that could land you in jail with DWI charges. Not only that, but now the prosecution will have concrete evidence of your DWI. It will be much easier for them to convict you with that information.

Refusing a breathalyzer test will ensure the prosecution never has scientific evidence of your arrest. Instead, they will have to rely on subjective police and eye-witness testimony. Your defense will have a much easier time dismantling the prosecution’s argument without that information, and the chances of dismissed or reduced charges will increase significantly.

Plus, it’s important to remember you can contest your license suspension with an administrative license revocation hearing. However, it’s important you work quickly. You will only have 15 days to file a request for a hearing. Once that time is up, you will lose your opportunity to challenge the suspension.

At the hearing, you and your attorney can provide evidence and argue why the license suspension shouldn’t be granted. They can also advocate on your behalf for a restricted license, which is a license where you have limited driving privileges. A restrictive license will allow you to commute to work, drop off your kids at school, and do other essential trips.


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What Can Cause a False Positive Breathalyzer Test?

Breathalyzers and other chemical DWI tests are technically based in science, but that doesn’t mean it’s a flawless process. Breathalyzers and intoxilyzers can yield skewed BAC readings due to several outside and internal factors including poor maintenance, faulty sample storage, issues within the chain of authority for testing, and other factors.

Listed below are some other common factors that could influence your BAC results.

  • The device was calibrated incorrectly
  • The officer didn’t follow protocol
  • You took cold medicine before driving
  • The officer misread the results
  • You have acid reflux
  • You work with a type of paint, lacquer, cleaning solvents, or other alcohols
  • You hiccuped, belched, or vomited before the test
  • You’re on a diet
  • You have traces of alcohol in your mouth
  • You have a slow metabolism
  • You’re diabetic
  • The temperature of your breath
  • Electromagnetic interference with the device
  • You have traces of alcohol in your mouth

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DUI Breathalyzer Limit for Texas

The state of Texas has different driving limits depending on the type of drivers. Listed below are the alcohol limits for Texas drivers and residents.

  • Adult Drivers Over 21 Years Old — .08 %
  • Commercial Driver’s License Holders — .04%
  • Underaged Drivers — Zero Tolerance Policy

It’s important to note, Texas has a zero-tolerance policy for drivers under the age of 21. Any driver under the age of 21 cannot have any amount of alcohol in their system. If they blow anything over 0, then they will automatically receive a driver’s license suspension.


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Additional Resources

Breathalyzer Manual for Law Enforcement in TX– Visit the official website of the Texas Department of Public Safety (DPS) to learn more about breath analysis and how a breathalyzer is used as directed by law enforcement. Access the document to learn the history of breath analysis, procedures and maintenance of both intoxillyzers and breathalyzers.

Implied Consent Laws in TX– Visit the official website of Texas Penal Code to access the statutes surrounding implied consent laws, also known as DWI refusal laws. Access the statute to learn more about the penalties for refusing to submit to DWI testing, what happens if someone is incapable of refusal and required information provided by the officer.


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DUI Breathalyzer Brownsville Attorney, TX

If you or someone you know have been accused of DWI because of a breath analysis test, then contact The Gracia Law Firm, P.C. The Brownsville DWI lawyers at The Gracia Law Firm, P.C. understand the complexities behind chemical testing, especially breathalyzers. Our legal team can utilize that knowledge to challenge your BAC results in court. Learn more about your legal options by calling our office at 956-504-2211.

The Gracia Law Firm, P.C. accepts clients throughout the greater Cameron County and Willacy County, Texas area.


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