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Factors affecting breath test results may lead to wrongful charges

There are certain factors that can affect the blood alcohol content reading obtained from a breath test device, making the results inaccurate.

When Illinois law officers pull a driver over on suspicion of drunk driving, they will most likely use a breath test device to determine whether the driver is intoxicated. According to the Illinois implied consent statute, drivers in the state automatically agree to submit to a breath test when asked by officers. Yet the results from these breath test devices are not always accurate and may be inflated depending on the circumstances of the case. In some situations, drivers may be erroneously charged with drinking and driving, even though their actual blood alcohol content is within legal range.

Research published by the State University of New York at Potsdam showed that various factors found in the environment can skew breath test results. In one study, a person who had not had any alcohol to drink had a breath test reading of 0.12 percent. The subject’s breath alcohol content was measured approximately 20 minutes after applying a gallon of paint to a wall and brushing contact cement on plywood. Since this BAC greatly exceeds the legal limit of 0.08 percent in Illinois, the subject would have been arrested and charged with drinking and driving if tested on the side of the road.

Environmental and physical factors

Certain compounds found in the environment, as well as unique physical variances have been found to affect breath test results. These compounds can alter breath test readings in as many as one out of every four drivers, according to the State University of New York at Potsdam. Breath test results can be altered by the following:

  • Dirt, pollution, moisture or smoke in the air
  • Electrical interference from certain devices, including police radios and cellphones
  • Air temperature
  • Paint, gas and other strong fumes

People, who have residual food, mouthwash, blood or vomit in their mouths, may have elevated breath test results as well.

Comparing breath and blood samples

Breath test devices measure a person’s blood alcohol content level indirectly by searching for the presence of ethyl alcohol in a breath sample. Blood tests, on the other hand, are more accurate in finding the exact BAC level. Breath test machines do not account for individual variances in how people absorb and metabolize alcohol. People who have a higher red blood cell count or are more physically active can have breath test readings that are higher than actual blood test results.

Taking action

If you have been charged with drunk driving in Illinois, you may want to consider speaking with a defense attorney regarding your legal options and rights. You are entitled to fair representation in court. A DUI can have serious effects on your life for years to come. An attorney may be able to minimize the legal repercussions of a DUI.

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