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How Accurate are Breathalyzers?


A Breathalyzer is a breath-testing tool commonly used to measure the Blood Alcohol Content (BAC) of a person’s body to determine if they are impaired by or under the influence of alcohol. These measurements have become a standard by which police officers judge the legality of a person’s actions and make DUI convictions and arrests. While breath testing is not the most accurate method of determining BAC, it is the least invasive and easiest for police officers to perform during traffic stops. Studies in recent years have shown however that the margin of error between breath testing and blood testing is very large. As a result, it is becoming increasingly justifiable for Gilbert DUI lawyer Charlie Naegle to contest 1st DUI offense, 2nd DUI offense, or multiple offense DUI cases based on the inconclusive outcome of a breathalyzer test.

Breathalyzer devices come in a couple variations of quality and price range. Some use semiconductor sensors, which are made of a cheaper material (and therefore less accurate) than the platinum fuel cell sensors found in professional quality Breathalyzers. Several factors can influence the reading on either device. The presence of other chemicals in the mouth or breath that are similar to alcohol (such as naturally occurring ketones, and mouthwashes or medications that contain alcohol) may skew the results. External factors such as the amount of time elapsed between tests, the temperature of the device, calibration of the device, and technological glitches, while rare, could also contribute to inaccuracy in breath test results.

While Arizona law clearly states that a BAC level of .08% or higher warrants an arrest for DUI due to the potential harm that one can cause behind the wheel of a vehicle, studies have shown that Breathalyzer readings, when compared to BAC levels drawn from blood, can vary by a minimum of 15 percent! The difference between a reading of .05% and .20% could mean the difference between facing years imprisonment and astronomical fines or facing no consequences whatsoever.

Working with a Gilbert DUI Lawyer

For DUI cases, where accuracy down to the decimal point is critical, a single breath test is rarely accurate and inconclusive. Mesa DUI attorney Charlie Naegle has been working for years to defend those accused of DUI charges and eliminate the occurrence of unfair court rulings and unnecessary arrests. He typically advises people to refuse submission to Breathalyzer tests because they are not always accurate. While an officer may still place you under arrest if he has probable cause, a failed breath test (that may possibly be inaccurate) will not help your court case. For more information on breath testing or getting legal representation from an experienced Mesa DUI lawyer and Gilbert DUI lawyer, call Naegle & Crider Criminal Defense Attorneys today to schedule your free consultation.

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