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How DUI Breath Test Results Can Be Skewed or Exaggerated


When looking to secure a driving under the influence (DUI) arrest – and ultimately a conviction – law enforcement agents lean heavily upon breath tests to record a suspect’s blood alcohol concentration (BAC) level. According to theory, a puff of breath can accurately represent how much alcohol is in a person’s system based on how much alcohol is in their breath. If a breathalyzer reports a BAC level over the legal limit, the police officer is free to make a sound arrest. At least, that is how it pans out on paper.

In reality, breath tests and the BAC levels they report are largely unreliable. A number of outside factors can skew a breath test result and give the officer an exaggerated BAC level read out. If this is taken at face value and no defense is put up by the defendant, then it could feasibly lead to an unjustified DUI conviction.

Factors that can skew a DUI breath test and give an unrealistically high BAC level include:

  • Acid reflux: Probably the most likely issue that will skew a BAC level report is acid reflux, or just burping. A person with stomach problems will slowly process alcohol and may belch a “fresh” reading of alcohol hours after actually having a drink. People who are pulled over for a DUI should be closely monitored by law enforcement agents for at least 15 minutes before taking a BAC test to ensure acid reflux or burping does not tamper with the results.
  • Body temperature: BAC levels are calculated under the assumption that the suspect has an internal body temperature of 98.6 degrees Fahrenheit, or the accepted average for most people. However, the average is not the only possibility. Many people maintain a body temperature slightly higher or lower than 98.6 degrees Fahrenheit. The higher a person’s body temperature, the higher their BAC readout will be, and potentially making a person’s intoxication appearing to be much worse than it is in actuality.
  • Medicines: Certain medicines will interfere with BAC readings if they were taken recently. Methyl compounds in particular are notorious for spiking BAC readings, which mistake the substance as a form of ethyl alcohol. Diabetics are often required to take some form of methyl compound to control their blood sugar, which unfairly makes them more prone to “failing” a breathalyzer test.

DUI Defense Representation in Sonoma County

Were you arrested for a DUI after reportedly failing a breath test? It might be possible that your BAC level was read at too high a number due to an outside source skewing the result! Stand up for your rights and learn how to shield yourself from an unfair charge or conviction by working with the Law Offices of Evan E. Zelig, P.C. and our Santa Rosa DUI attorney. Start today with a complimentary case evaluation by contacting our firm at your first opportunity.