Five Ways a Texas DWI Breath Test May be Distorted


Breathalyzers have been used for decades across the country to bring charges against drunk drivers. Many Texas motorists who fail a breath test make the mistake of believing it is foolproof and they should plead guilty. However, there are many factors that can skew a breath test and invalidate a charge.

Breath tests in Texas are extremely unreliable for a number of reasons. An experienced criminal defense lawyer can find flaws in these tests and highlight them in court.

The margin of error in breath tests is much higher than most drivers imagine. According to the National Motorists Association, breathalyzer tests are often unreliable, resulting in a margin of error as high as 50 percent. Here are some of the reasons why breath tests may distort results.

1. A Police or a Highway Patrol Officer Improperly Calibrated the Machine

Breath test machines must be calibrated regularly. They should be properly maintained by officers qualified to do so. Often law enforcement departments cut corners. Breath machines respond to changes in ambient temperatures. They will provide false readings if they are not calibrated to respond to these changes in temperature. If a criminal defense attorney can prove that a police officer failed to properly calibrate the breathalyzer or that the machine regularly gives false readings, the court may declare the results of the breathalyzer test inadmissible in court and the DWI charge will be thrown out.

The issue with inaccurate breath machines goes beyond that of calibration. Research has pointed to flaws in some makes of breathalyzer including a popular model manufactured by a German company, reports ZDNet.

2. The DWI Suspect Has a Medical Condition

In some cases, medical conditions may skew a DWI test result. Some conditions including acid reflux, Gastroesophageal Reflux Disease (GERD), and heartburn can impact test results and boost alcohol levels in the suspect’s mouth. Other conditions that can skew a breath reading include diabetes and hypoglycemia

These conditions may cause a false reading. If the defendant can show he or she suffered from one of these conditions, this information may have a bearing on a conviction.

3. Mouth Alcohol is Present from Other Sources

A DWI suspect may test positive in a breathalyzer test because of the presence of residual alcohol from other sources.

Alcohol can be trapped in a suspect’s mouth via dental work that absorbs small amounts of food containing traces of alcohol in the suspect’s teeth. Other substances like mouthwash can contain alcohol. Factors like burping or vomiting also impact breath tests. If a test is borderline, these factors may produce a false positive result.

4. Food Influences a Test Result

Certain diets may influence the outcome of a breath test. A low carb diet can impact a breathalyzer result. A low daily carbohydrate intake boosts ketosis in the body. The body compensates by using fats for energy instead of carbohydrates. Ketones are also released in urine. They can trigger a higher reading on a breath machine.

Dieting, fasting, and having a high protein or low carb diet may impact your breathalyzer results. People on an Atkins-type diet are more likely to give a falsely high BAC in a test.

5. Tests Are Improperly Administered

Police may not use proper protocol before administering a breath test. Police are meant to observe a suspected drunk driver for 15 minutes before giving a breath test. They often administer field sobriety tests in this time. These tests are notoriously unreliable and a suspect should refuse them. It’s important that an officer carefully observes the suspect for some time before conducting the test. Even a belch can skew test results.

Results above the .08 legal limit will land a driver in jail in Texas where he or she will be required to submit to a breath or blood tests in custody that can be used in court.

The penalties for DWI are high in Texas. A conviction can deprive you of your livelihood, liberty, and education. Driving while intoxicated is one of the most common crimes in Texas. If you have been charged with this offense you should hire an experienced Dallas DWI attorney as soon as possible.

At Broden & Mickelsen, LLP, we are experienced Dallas criminal defense lawyers are dedicated to providing aggressive and ethical representation to individuals and businesses charged with crimes.