Why are Breathalyzer tests flawed?

On Behalf of | Jan 6, 2019 | Uncategorized

Imagine a police officer pulls you over late one night while you’re driving. The officer suspects you’re drunk, so he asks you to step outside of your vehicle for a few DUI tests. You had a couple of drinks that night, but you feel perfectly sober, so you’re not worried.

True to your belief, you stood on one leg, walked heal-to-toe and recited the alphabet backward in perfect form. You passed the field sobriety test, but when it came to the Breathalyzer, you failed it miserably. As the officer put on the cuffs and read your Miranda rights, you couldn’t believe what was happening.

During the entire ordeal, one thought kept racing through your disbelieving mind: “How can I be arrested for DUI when I’m not even the slightest bit drunk?”

The truth is, Breathalyzer tests are not always accurate. Every criminal defense attorney, every criminal court judge and every prosecutor knows that these devices are prone to giving false results. For this reason, if the primary piece of evidence being used against you in your DUI case is a failed Breathalyzer test, you might be able to defend yourself against the charges. Indeed, evidence of a failed breath test does not create a “slam-dunk” case for the prosecution.

Here are two common reasons why breath-alcohol tests can be inaccurate:

Not all human beings are identical

Some people are big, some are small. Some are underweight and some are overweight. Some are muscular and some have very few muscles at all. Similarly, when human beings exhale after drinking alcohol, certain subjects exhale more of the alcohol in their bloodstreams than others.

Scientists estimate that — on average — people exhale approximately 1/2100th of the alcohol contained in their blood. So they take the amount of alcohol found in the breath during a Breathalyzer test and multiply it by 2,100 to arrive at the blood alcohol content percentage. The problem is, every person is different because they breathe at different rates and have different body temperatures. This can render many Breathalyzer tests completely inaccurate.

Breathalyzer devices are sometimes calibrated wrong

Police must keep their Breathalyzer devices calibrated properly. Recommended maintenance on a Breathalyzer suggests calibrating them approximately every 10 days or after 150 uses. Breathalyzer devices also should be rigorously tested at specific intervals to show that they render results with a margin of error of .02 percent. When a breath test device does not receive regular tests and maintenance, a defendant might be able to cast doubt on its accuracy.

There are a wide variety of reasons why a Breathalyzer test could be inaccurate. Therefore, if you suspect that the breath test relating to your DUI test was wrong — and you’re facing inappropriate DUI charges as a result — you may want to learn more about this important issue while defending yourself against the charges.