DWI

Killeen Breathalyzer and Breath Tests Defense Attorneys

Challenging the reliability of breath tests in Harker Heights, Waco, Copperas Cove, and throughout Central Texas

Breath tests are the most common way a driver can be found guilty of driving while intoxicated in Texas. They examine the blood alcohol content (BAC) of the driver by using breathalyzer machines. These delicate machines need to be accurate to determine the amount of alcohol in a driver’s blood.

At Mary Beth Harrell Law Firm, our skilled Killeen breath test lawyers use numerous arguments to challenge the admissibility of these tests. This includes legal arguments such as the authority to use the breathalyzers and the basis for stopping the driver in the first place. We also assert factual arguments such as that the officer failed to administer the test correctly. Many people who are sober do fail breath tests. Even if your results are high, we may able to show that that that a high BAC result may not accurately show what your level was when you were actually driving.

What are the BAC amounts that can result in a DWI charge?

Drivers whose BAC is at or above the following amounts can be charged with driving while intoxicated in Texas:

  • .08 for any driver. This is the legal limit across America.
  • .04 for a commercial driver. Commercial drivers are generally anyone with a commercial driver’s license, like truckers.
  • .02 for minors. This strict BAC limit applies if a driver is under 21. This generally means any amount of alcohol can be detected.
  • .15 for any driver. In this case, a DWI offense will be upgraded to a Class A misdemeanor instead of a Class B misdemeanor.

Intoxication is also defined as “not having the normal use of mental or physical faculties by reason of the introduction of alcohol, a controlled substance, a drug, a dangerous drug, a combination of two or more of those substances, or any other substance into the body.”

Generally, in DWI cases where the BAC is above one of these limits, our attorneys fight charges by showing that the breath test is either inadmissible, unreliable, or that there are extenuating circumstances.

Which breathalyzer tests are used in Texas?

Blood alcohol concentration (BAC) means the number of grams of alcohol per 210 liters of breath. According to the Texas Breath Alcohol Program Operator Manual, breath testing instruments must meet the following requirements:

  • Expired breath specimens need to be analyzed
  • The device must use a reference system where the results agree with +/- .01g/210 L of the nominal value or such limits as set by the Scientific Director
  • The procedure should be appropriately and adequately specific for the determination of alcohol concentration for law enforcement.
  • Other tests that the Scientific Director deems required must be met. For example, the Director requires that the officer stay in the subject/driver’s continuous presence for 15 minutes before the test is given and should use reasonable care so that that the person taking the test doesn’t place anything in his/her mouth.

One breath machine that Texas has approved for law enforcement is the Intoxilyzer 9000. The Intoxilyzer 9000 uses the scientific principle of “infrared spectrometry.”

What factors can affect BAC results?

Some of the factors that skilled DWI breath test lawyers review, sometimes with the help of breathalyzer machine experts, include:

  • The temperature of the person who took the test can affect the results
  • The depth of your breath when you breathe into the breathalyzer machine can affect the results
  • The breath tests results can vary if you have any physical conditions such as heart problems or diabetes
  • Gender can affect the results. Generally, females have higher BAC results because breath machines are usually calibrated to examine the typical male. The manual specifically states that if “a man and woman of the same weight and body build ingest the same amount of alcohol, the woman will most likely achieve a higher alcohol concentration. Ethanol is removed from the body through metabolism and excretion.”
  • The variance of the test results may indicate a problem with the breath tests or the breath test machine. The driver should be asked to take at least two breath tests.
  • The officer should also clearly explain how the breath test machine works. A failure to give multiple tests or to explain the breath test procedure can be grounds for dismissing the breath test results.
  • A person’s body type and total body water can affect the test results

Each test operator must be certified on a yearly basis – by November 1 of each year. In addition, every other year, the officer must complete a renewal course and a renewal exam.

How can you challenge breath test results in Central Texas?

Breath tests can be contested based on a variety of defects. These include:

  • Use of breath test machines that haven’t been approved
  • Use of breath test machines that haven’t been properly validated
  • Use of breath tests administered by an officer who isn’t certified
  • Failure to maintain the equipment properly
  • Failure to administer the test properly

Other challenges may apply, depending on the basis for stopping you in the first place, when the test was given, and where it was given.

What if I refuse to take a breathalyzer test in Central Texas?

Texas has an implied consent law which requires that all drivers submit to a breath test (provided the police officer had grounds to request the breath test). Drivers who refuse a breath test will face an administrative license suspension, which can result in a loss of your driver’s license for up to 180 days. Drivers do have the right to contest the license suspension at an administration license suspension hearing – within 15 days. A subsequent refusal can result in a two-year suspension.

Consult with a Killeen breath test and DWI defense lawyer

The Mary Beth Harrell Law Firm has been fighting for the accused for more than 20 years. We’re upfront about the merits of your case. We guide you through each stage of the criminal justice system, and have the skills and resources to contest the admissibility of breath tests. We can assert your rights if you refused to take a breath test. To speak with an experienced Texas breath test DWI lawyer, call us at 254-680-4655 or fill out our contact form. We have offices in Killeen, Harker Heights, Waco, and Copperas Cove.