Breath tests that are used to determine blood alcohol concentration (BAC) can sometimes yield inaccurate results. Drivers need to be aware of this because many people assume that failing a breath test guarantees an impaired driving conviction. It does not.
It’s also worth noting that a breath test is just part of the equation. Officers may also consider factors they observe – slurred speech, bloodshot eyes, etc. – and field sobriety tests when making a determination about whether or not a motorist is impaired. But since breath tests provide “concrete” evidence, it’s important to know why that particular kind of evidence may not be as trustworthy as people believe.
7 reasons for inaccurate results
Every case is unique, of course, but here are some examples of common reasons why breath test results might be wrong:
- Residual mouth alcohol: Consuming alcohol shortly before the test can leave residual alcohol in the mouth, leading to a higher BAC reading. This could be due to using mouthwash, breath fresheners or even burping, which can introduce alcohol into the breath sample.
- Medical conditions: Certain medical conditions can generate acetone or other compounds in the breath, which may interfere with the accuracy of the breath test, resulting in a falsely high BAC reading. Examples include GERD (gastroesophageal reflux disease), acid reflux or diabetes.
- Breathing patterns: Hyperventilation or holding one’s breath prior to blowing into the breathalyzer can potentially affect the accuracy of the test. Hyperventilation might dilute the alcohol concentration in the breath sample, while holding one’s breath might increase it.
- Environmental factors: External substances or environmental contaminants, such as paint fumes, cleaning products or gasoline vapors, could interfere with the breath test and lead to an inaccurate reading.
- Calibration and maintenance issues: Improper calibration or maintenance of the breathalyzer device can cause inaccuracies in the readings.
- Device malfunctions: Like any electronic device, breathalyzers can malfunction. Technical issues or errors in the device itself can produce incorrect results.
- User error: Incorrect usage or administration of the breath test by law enforcement officers or individuals administering the test could also contribute to inaccurate results.
It’s essential to remember that, while breath tests are commonly used to estimate BAC, they may not always provide completely accurate readings. If you have been arrested and you think that your test results are inaccurate, you also need to know about your legal defense options. Remember that a drunk driving conviction could cost you in terms of a license suspension, fines and fees, time behind bars, lost wages and more. You do not want to be convicted erroneously. As such, seeking legal guidance is wise.