Ways a Breathalyzer Could Be Faulty

Law enforcement officials often use a device known as a breathalyzer to determine the blood alcohol level of an individual suspected of DUI or DWI. Portable breathalyzer devices are used in the field, while stationary devices, usually housed at the police station, are larger (and considered to be more accurate). There are many different brands of breathalyzers; however, they all essentially work in the same manner. They measure the alcohol content from your breath—as opposed to alcohol blood tests, which more directly—and accurately—measure BAC. Although the breathalyzer is widely accepted as a means of "proving" BAC, the results of the device are actually nothing more than an estimate. Unfortunately, this "estimate" can be influenced in a number of ways.

According to a 2019 New York Times article, as many as a million Americans are arrested each year for drunk driving. The primary method of conviction for those arrested is the breathalyzer device. If your BAC reading is 0.08 percent or higher, it is highly likely you will be convicted of DUI. Yet judges in both Massachusetts and New Jersey threw out more than 30,000 breathalyzer tests in 2019 due to “human errors and lax governmental oversight.”

Across the nation, more breathalyzer tests have been invalidated. The NY Times article notes that, first and foremost, when a breathalyzer has not been properly calibrated, the results can be as much as 40 percent too high. Further, technical experts who tested the breathalyzers used to convict those arrested for DUI have discovered serious programming errors in the machines’ software. The Times interview revealed the depth of a very serious problem—faulty breathalyzer results.

Factors That Can Affect Breathalyzer Results

While the portable breathalyzer devices are relatively inexpensive and easy to maintain, the results have been proven to be wildly inconsistent. Factors which can throw off the results of a portable breathalyzer machine include:

1. Older women, in particular, often have trouble producing enough breath to allow the machine to work correctly.
2. Some types of toothpaste, mouthwash, and even breath mints can alter breathalyzer results.
3. Burping prior to taking the test can alter the test results.
4. A person whose job causes them to regularly breathe in propane, varnish, oil-based paint, or gasoline can have false high results when taking a breathalyzer test.
5. Those who are diabetic or who are on the Atkins or another type of low-carb diet can produce acetone on their breath, which skewers the results of the breathalyzer test.
6. A person with periodontal disease or a person who has vomited shortly before taking the breathalyzer test can test falsely high.
7. Certain medications, including Albuterol and other inhalants used to treat asthma, Nyquil, cold medicines, and toothache medicines, can produce a false positive result on a breathalyzer test.
8. Those who use smokeless menthol tobacco can test falsely high on a breathalyzer test. 
9. Body temperature and air temperature can significantly alter breathalyzer test results. Having a fever can increase BAC reading and, if the device is not calibrated or adjusted to account for outside temperature, the reading may be incorrect.
10. Eating an extremely spicy or extraordinarily greasy meal prior to taking a breathalyzer test can cause a false positive.
11. Any device containing electronic circuitry—like a breathalyzer device—can receive electromagnetic interference, which then skewers the results.
12. Gastroesophageal Reflux Disease (GERD) can directly affect the results of the breathalyzer test, possibly creating a false positive reading or a test reading error
13. When police officers lack training in the use of breathalyzer devices or are simply inexperienced, the results may not be accurate.

Were You Arrested for DUI?

If you have been arrested and charged with DUI, it is extremely important that you speak to an experienced DUI attorney who can help you determine whether your BAC reading was accurate or was influenced by an outside factor. You deserve a strong defense as well as an advocate in your corner who will ensure your rights are properly protected.

The experienced lawyers at Lewis & Laws, PLLC, have successfully defended clients in Seattle, Bellevue, and Kirkland. Contact us today at 206.209.0608 or fill out our online contact form.