If you have ever been pulled over by a Connecticut law enforcement officer on suspicion of driving under the influence of alcohol, you may have been asked to take a breath test. Breath test devices are often used by law enforcement officers to measure a driver’s blood alcohol content level and ensure they are not over the legal limit of 0.08. Yet, in some cases, the readings from these breath test devices may not be accurate and could lead to a wrongful DUI arrest and charges. 

Researchers from the State University of New York at Potsdam found that breath test devices measure more than simply the amount of alcohol in an exhaled breath sample. The device also picks up substances that have a similar molecular structure. Furthermore, there are substances in the environment that can skew the results as well. In fact, breath test readings can vary by as much as 15% when compared to the BAC found from an actual blood test. This means that at least one in four people who take the test will show inflated readings

What is it that causes these altered results? The following can cause inaccurate breath test readings:

  • Cigarette smoke, dirt and pollution in the air

  • Electrical interference from cell phones and police radios

  • Residual vomit, food, blood or liquid in the mouth

  • The relative humidity and temperature of the air

  • Fumes from gasoline, cleaners and paint

When officers are unsure of how to use the breath test devices properly or if the device is not calibrated to work correctly, the results can be affected. 

This information is intended to educate and should not be taken as legal advice.