The vast majority of those convicted of a DWI/DUI in Missouri have faced evidence from a BAC (blood alcohol content) test. While some of these tests are done directly on the blood, most are conducted using a handheld breathalyzer machine carried by law enforcement officers. While breathalyzers can be accurate and reliable, there are several ways that their readings can be inaccurate – and therefore not helpful in an DWI conviction.
How Breathalyzers Work
A breathalyzer analyzes the amount of ethanol contained in your breath and converts that amount into an estimate of your blood alcohol level. As you might guess, while this can be an accurate reading, several factors can change the readout so that a sober driver blows a readings that is above the legal limit.
How Breathalyzer Tests Can Go Wrong
There are four major ways that a breathalyzer test can produce an inaccurate reading. Let’s take a closer look.
- The breathalyzer isn’t properly calibrated. Breathalyzers are delicate instruments that analyze the chemistry of your breath – and they have to be calibrated and maintained properly. If the machine used during your stop hadn’t been properly cared for, it could have easily given the wrong reading of your BAC.
- The officer is not properly trained to use the breathalyzer. Not only must breathalyzers be calibrated often, they also have to be administered correctly by a trained officer. For example, an officer may fail to give you the proper waiting period before administering your test, or he or she may give the test incorrectly in any number of other ways. Two tests must have results within .02 of each other – if they don’t, you may have a case.
- Some health conditions could affect the result. Since the breathalyzer can be affected by alcohol in the stomach or mouth, or by compounds that are similar to ethanol, health conditions such as acid reflux (also known as GERD or heartburn) or diabetes could affect the reading. In addition, some dieters whose bodies are going through ketosis may also produce higher false readings. Finally, there’s some evidence that having a high body temperature can affect the reading, since BAC is calculated based on a normal body temperature.
- Some chemical exposures could affect the result. In the same way that some health conditions can affect results, some chemical exposures can also render a reading inaccurate. People who work with paint, cleaning fluids, varnish, paint remover, lacquer, gasoline, celluloid, cement, or methyl tert-butyl ether could have a higher false reading. People who recently used an alcohol-based mouthwash or breath fresheners could also be affected.
Speak To A St. Louis DWI Attorney About Your Breathalyzer Test Results
The best way to know if your breathalyzer test might not have been accurate is to speak to an experienced St. Louis attorney about your charges. At the Shostak Law Firm, we will review all of the evidence available from your case and work with you toward the best possible outcome. To learn more about our legal services, or just to ask a question about your case, contact us today. Need more information? Read our free e-book, Missouri DWI Survival Guide to make an informed decision about what to do next.