Written by attorney Todd F. La Neve

Are DUI Breath Testing Machines Accurate?

In short, no. The breath testing devices on the market today are one-size-fits-all technology. If it doesn't work for ballcaps, why should we trust it for determining if someone goes to jail or not?

The breath testers on the market now are based on mathematical algorithms that must, by design, use a number of average values to fill in the variables in the math equation. The reality is that people are all different and the machines cannot be adjusted to account for those differences. So, the end result is that the machine assumes you and everyone you know are physiologically identical.

Many different factors impact how the breath machine reads a person's breath sample. Among them are physiological, medical, environmental, and physical factors. Diseases such as acid reflux, asthma, COPD, and ulcerative colitis can all cause falsely elevated readings due to the way they influence the breath sample being provided. Physical problems such as reduced lung capacity can negatively affect various assumed valued in the math equation the machine runs on and lead to artificially elevated results. Exposure to various chemicals can cause residual amounts of those chemicals to appear in the breath sample and the machine often cannot account for the presence of that substance because many of the machines are not able to differentiate ethanol - the alcohol in alcoholic beverages - from other substances with similar molecular structures.

All in all, alcohol breath testing is flawed science that is developed and produced for law enforcement at the urging of law enforcement and governmental agencies. Many of the manufacturers of these machines refuse to allow anyone outside of government and law enforcement to see the programming behind the machines or to even own or inspect the machines. Such secretive behavrior by the manufacturers causes one to stop and really question why this is happening.

When facing a DUI charge, don't ever make the mistake of just assuming that because the government's machine says you broke the law, that you actually broke the law. The discussion above shows just some of the reasons the machine may be producing the results that you see on paper and on which the state is relying to prosecute you. Hire an attorney who is experienced in defending against breath test results and give yourself a chance to show the real truth behind the numbers.

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