Common Reasons Why a DWI Breath Test Can Be Wrong

Throughout the year and especially during holidays, law enforcement officers in Texas crack down on suspected drunk drivers. But many DWI arrests aren’t valid, given the sometimes faulty results of roadside breathalyzer tests. This is why it’s important to know the reasons why breath tests can be wrong by inaccurately showing an illegal level of alcohol in the blood.

What many people don’t realize is that breathalyzers don’t actually measure the alcohol in a driver’s blood, but rather the alcohol in the air emitted by the person’s breath. The reading of alcohol in the air is converted into an estimate of the alcohol level in the blood, via a formula.

The legally drunk limit for drivers in Texas (and almost every other state) is a blood alcohol content (BAC) of 0.08 percent. Drivers whose breath test registers at that amount or higher can be arrested for driving while intoxicated, or DWI.

Health factors can cause wrong breath test results

As recently reported by the New York Times, breathalyzer tests aren’t always trustworthy. Our law firm has been saying that for years — and there are many reasons for the problem. For one thing, health factors can cause incorrect breath tests.

Many people suffer from acid reflux and gastroesophageal reflux disease, or GERD. The vapors and gases accompanying such conditions can lead to major inaccuracies in a breathalyzer test — inaccuracies which might falsely suggest that the person is drunk, when they’re actually just suffering from a stomach acid problem. With GERD, undigested alcohol may rise in the digestive tract to create a higher concentration of alcohol in the breath.

For individuals with diabetes, an elevated amount of ketones in the blood can cause an elevation in acetone in their breath. Some breathalyzer kits are sensitive to acetone and may register it as alcohol by mistake. In fact, a breathalyzer cannot distinguish between acetone and ethyl alcohol.

Also, the dentures worn by some people can trap alcohol in the mouth and skew the results of a breath test. In addition, the periodontal disease suffered by some people can create pockets in the gums which can hold alcohol for a longer amount of time. On a breath test, this may indicate more alcohol than is actually in the person’s bloodstream.

Even hiccuping or belching can show heightened levels of alcohol. A hiccup or a belch can bring gas from your stomach — including traces of alcohol — into your mouth. Breath tests should not be given within 15 minutes of a belch or a hiccup.

Mouthwash can skew a breath test

Did you use a mouthwash or a breath freshener shortly before driving?

Ethanol is the same type of alcohol which is part of alcoholic beverages, and the ethanol in many mouthwashes can create a “false positive” result in a breathalyzer test.

Other health products containing traces of alcohol can also lead to an incorrect breath test.

Low-carb diets can affect DWI arrests

Believe it or not, the food that you eat — or don’t eat — can lead to an incorrect reading of blood alcohol, followed by a costly DWI arrest. That’s because today’s popular low-carb or carbohydrate-free diets (such as keto) can create such a false positive.

How?

A significantly low intake of carbohydrates can cause your body to go into a state of ketosis, in which it relies on fat for energy rather than sugars. Ketones produced in this process  can also create an incorrect reading of BAC in a breath test.

Warm breath an aerobic activity

In addition, breathalyzer misreadings can occur when your breath is particularly warm, such as after exercising. Warmer breath may indicate a higher than actual BAC content.

Time can be a factor

Also, time can be a factor in an inaccurate breath test, since such tests assume that your body is well past the absorption phase for alcohol to be in the bloodstream.

The body can continue absorbing alcohol for up to 2 hours after drinking — or even longer, given some people’s slower metabolism. If the test is given while the body is still in the absorption phase, based solely on alcohol in the air of the lungs, the results won’t be accurate.

Defective equipment can impact BAC results

Defective breathalyzer equipment and faulty maintenance of such equipment can impact the BAC results as well.

The breathalyzer and intoxilyzer devices commonly used in roadside sobriety tests in Texas are often not properly calibrated, or haven’t been recalibrated recently. This can lead to false positive results.

Calibrating a breathalyzer regularly is important because its silicon oxide sensor, which is used to calculate blood alcohol concentration, can lose accuracy over time and degrade. These sensors must be recalibrated frequently to focus their ability to detect an accurate reading.

Untrained officers can get false results

Not all law enforcement officers are properly trained in administering the kind of handheld roadside breath tests given to suspected drunk drivers. When officers lack sufficient experience or training, operational errors may negate the accuracy of such tests.

Electronic interference can be a problem

Another problem that commonly affects roadside breath tests can be electronic interference from radio transmissions via police radar devices, handheld police transmitters, police station dispatchers or even FM or AM radios.

Occupations can even affect BAC results

Even your job or occupation can adversely affect the BAC results of a breathalyzer test.

Some people work with such elements as gasoline, lacquer, varnish, oil-based paint, paint remover, cement, celluloid, cleaning fluid and other high volatile organic compounds, or VOC chemicals. Their breath may retain enough fumes from such chemicals to cause a false positive on a breathalyzer, which is unable to distinguish between alcohol and such compounds.

You need the best Houston DWI defense lawyer

Did you or a loved one recently fail a breathalyzer test?

As you can see, many things can improperly influence the results of such roadside tests. Fortunately, challenging a breathalyzer test is just one of many things an experienced DWI defense lawyer can do to protect your legal rights.

Contact the Neal Davis Law Firm for a legal review of your case. A DWI conviction for an intoxication offense can be extremely costly, leading to jail time and high fines. Let’s get started protecting your rights, especially when an arrest may have been due to an inaccurate breath test.