Contesting the Breathalyzer Test

The breathalyzer test works by measuring the number of alcohol compounds in a sample of deep lung air and calculating the amount of alcohol in the blood. If the machine finds that your BAC calculation is .08% or higher, you may be charged with drunk driving.

To ensure that the results of the breathalyzer are accurate, the machine must be calibrated and maintained on a routine basis in accordance with the manufacturer’s specifications. A defense attorney can request a copy of the breathalyzer’s calibration and maintenance logbooks to determine if the machine was in good working order. If it was not, your BAC reading may be challenged.

There are certain biological factors that could have an impact on the test. For example, when performing the breath to blood calculation, the machine assumes that the blood alcohol content to breath alcohol content is 2100 to 1. However, not everyone falls within this ratio, affecting the test results. In fact, having a fever could affect this ratio.

Common medical conditions could also render the test inaccurate. Diabetes, hypoglycemia and even low-carbohydrate diets could cause the body to go into ketosis, which produces compounds called “ketones.” Because this compound cannot be used by the body, it’s converted to isopropyl alcohol, which can be mistaken by the breathalyzer machine as alcohol that is consumed.