While Tennessee law relies heavily on breath tests to measure blood alcohol content, these devices are not perfect. A breathalyzer analyzes alcohol vapor from your lungs, but various factors can interfere with its accuracy.
A seemingly small measurement error can have major consequences for your driving privileges and freedom. That is why you need to understand why these instruments sometimes produce a falsely high result, even when you aren’t legally impaired.
Residual mouth alcohol
Alcohol lingering in your mouth or esophagus immediately before the test often causes a false reading. Sources like recent consumption, using mouthwash containing alcohol, or even burping or vomiting can leave trace amounts of alcohol. The machine incorrectly reads this concentrated mouth alcohol as alcohol coming directly from your lungs, leading to an artificially high reading.
Medical conditions
Certain medical conditions can confuse the breath test device. Individuals who suffer from gastroesophageal reflux disease (GERD) sometimes experience burping or regurgitation, which brings stomach acids and any alcohol present up into the mouth. Furthermore, diabetics suffering from ketoacidosis produce a compound called acetaldehyde, which the breathalyzer may mistake for ethyl alcohol.
Improper test administration
The person administering the test must follow specific procedural rules to ensure accuracy. Tennessee mandates a required observation period of at least 20 minutes before a test is given.
If the officer fails to observe you for this full period, you might have consumed something or brought alcohol into play just before the test. Improper calibration of the testing machine itself also produces unreliable results.
Challenging reliability of the device
Breath test results are powerful evidence for the prosecution, but they are not the final word. When your future hangs in the balance, you need an experienced advocate who recognizes these technical flaws and knows how to challenge the science.
A skilled attorney can scrutinize the testing process, the machine’s maintenance records, and your unique circumstances to uncover every possible defense. They can fight to ensure the judge hears your side of the story, not just the machine’s potentially flawed output.
