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DWI Breath Test

Law enforcement use all types of chemical testing to measure a person’s impairment level when driving. The most common method for DWI testing is breath analysis, which is commonly measured with a breathalyzer or an intoxilyzer. Both of these devices are used to measure your blood-alcohol concentration (BAC) with a breath sample from the impaired person.

A breathalyzer uses specialized reactive mixtures to measure blood-alcohol concentration. Although the instrument has improved over the years, a breathalyzer or intoxilyzer can give false results in certain circumstances. Specific factors such as incorrect calibration, faulty maintenance, human error or contaminated samples can all play a role in skewed results. This means you could be charged with driving while intoxicated (DWI) even if you never had a drop of an alcoholic beverage.

If you or someone you know has undergone and failed a DWI breath test, then it’s imperative you contact a skilled and experienced DWI attorney.

DWI Defense Attorneys for Breathalyzer Tests in Conroe, Texas

The information obtained from a breathalyzer test could be suspect if certain factors happen such as contaminated samples or faulty devices. That is why it’s highly recommended you secure legal representation if you’ve recently failed a breath test for driving while intoxicated.

A great option is to contact Evans & Powell, PLLC. Our experienced and skilled defense lawyers understand how stressful DWI accusations can be. We want to help you fight these charges and regain your reputation by effectively and efficiently defending you. Call us now at (713) 622 - 2000 to set up your first consultation absolutely free.

Evans & Powell, PLLC accepts clients throughout the greater Conroe and Montgomery County area including Willis, Montgomery, The Woodlands, Magnolia and New Caney.

Overview of Breathalyzer Tests in TX

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How Do Breathalyzers Really Work?

Both breathalyzers and intoxilyzers measure the level of alcohol within your blood by seeing the results of a chemical reaction. The breathalyzer is made up of two glass vials containing a chemical reaction as well as a system of photocells connected to the meter. The meter calculates color changes that happen when the chemical reaction happens.

The device calculates BAC by having someone enter a breath sample. The breathalyzer then processes the sample through a mixture of chemicals which include sulfuric acid, dichromate, potassium, silver nitrate and water. The mixture will turn from a reddish-orange color to a green if the sample is found to have ethanol in it, a component of alcohol. It is then procedure for law enforcement to compare the tested reacted mixture with an unreacted control mixture. Once this process ends, the device will have a blood-alcohol concentration (BAC) reading.

Breathalyzers can be handheld by singular police officers or full-sized at a police station. It’s important to remember a portable breathalyzer is much more susceptible to errors than a standard full-sized breathalyzer. Due to this, the prosecution typically will only rely on evidence from full-sized breathalyzer devices instead of portable breath tests (PBT).

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How Do Breathalyzers Give False Positives and Why?

Law enforcement relies heavily on breathalyzers and intoxilyzers so many assume it’s an accurate process. However, this cannot be further from the truth. Both breathalyzers and intoxilyzers can give false positives and not only that, but the risk and cause for error is much higher and vary more than you may think. Some factors that can influence the validity of a breathalyzer include metabolism, diet or even cold medicine.

If a breathalyzer or intoxilyzer isn’t maintained regularly, then the device may give false results. It can also give skewed positives if the device isn’t calibrated before use. Not to mention the human error that could occur from lab technicians or police officers handling the sample.

Listed below are some common problems that can occur in breath analysis.

  • You’re on a diet;
  • You have diabetes;
  • Electromagnetic interference with the device such as cellphone signals;
  • You have acid reflux;
  • The officer read the results wrong;
  • You have diabetes;
  • Electromagnetic interference with the device such as cellphone signals;
  • You have acid reflux;
  • The officer read the results wrong;
  • There are still traces of alcohol in your mouth;
  • You have a slow metabolism;
  • The device wasn’t calibrated properly;
  • You belched, vomited or hiccupped right before the test; or
  • The temperature of your breath

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Is it Ok to Refuse DWI Breathalyzer Tests in Texas?

Many are confused on how driving while intoxicated rules work when it comes to chemical or field sobriety testing. You might think you’re bound by law to submit to these tests, but you have the choice to say no. You can choose to submit to a breath analysis test if you’ve very confident you have a low BAC. However, it’s important to remember that there have been instances where perfectly sober people have failed a breathalyzer test due to other factors.

The risks associated with breathalyzer or intoxilyzer tests are sometimes not worth the risk. Blowing a BAC over .08 will automatically get you arrested for driving while intoxicated (DWI), but there’s a chance that this was simply a false positive made by the device. You will have your administrative license suspended for up to six months and there will be concrete scientific evidence the prosecutor can utilize at your trial.

Since breathalyzers can sometimes give false positives many defense attorneys advise you to exercise your right to refuse. Despite implied consent laws, you can refuse testing from law enforcement at any time. Although doing so will lead to other consequences. Refusing any chemical test will result in an administrative license suspension for up to 180 days. A second refusal will land you with a two-year license suspension.

Suspended licenses are a handle, but they are much simpler to contest than DWI charges. You can file a request to have an administrative license revocation hearing and there you can give reasons as to why you shouldn’t have your license revoked. It’s important you act now though because you only have 15 days to file a request for an administrative license revocation (ALR) hearing. If you and your defense lawyer are successful, then you can continue using your license or you may be granted a restricted license temporarily.

It’s imperative you know that you can be arrested if you refuse a breathalyzer test. If the officer has probable cause you’re intoxicated, then they have the right to arrest you even without a BAC reading. Some officers take a refusal as a sign of probable cause and will arrest you because of it.

Being arrested is never a pleasant experience. However, it doesn’t mean you’re automatically charged with driving while intoxicated (DWI). The arrest and booking is an temporary process and once you’re released the prosecution won’t have any hard evidence to use against you. It’ll be much more difficult for the district attorney to obtain a conviction if they have no BAC reading. That is why many lawyers suggest refusing a breathalyzer test when you’re pulled over by an officer for DWI.

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Additional Resources

Texas Breathalyzer Manual – Visit the official website of the Texas Department of Public Safety (TxDPS) to learn more about breath analysis and how they work. Access the document to learn the history, procedures, calibration and maintenance of both intoxillyzers and breathalyzers.

Texas Implied Consent Laws – Visit the official website of Texas Penal Code to access the statutes surrounding implied consent laws concerning DWI refusals. Access the statute to learn more about the penalties for refusal, what happens if you’re incapable of refusing and required information that must be given to you by the officer.

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Defense Lawyer for DWI Breath Test in Montgomery County, Texas

If you or someone you know has been arrested because of a failed breathalyzer test, our suggestion is to gain legal counsel immediately. With the right lawyer, you can avoid a DWI conviction and its penalties. Find the right representation for you by calling Evans & Powell, PLLC.

Our experienced and skilled attorneys have been working in the Conroe area for years. We understand thoroughly the science behind DWI testing and want to use this knowledge in court against your case. Call us now at (713) 622 - 2000 to set up your first consultation free.

Evans & Powell, PLLC accepts clients throughout the greater Conroe area such as New Caney, Splendora, Willis and Montgomery.


Evans & Powell, PLLC