The Common Law

Should I Take the Breathalyzer?

Should I submit a breath sample if pulled over and I've had a few drinks earlier in the night?

It is scientifically proven that Breathalyzers are often inaccurate and commonly unreliable, and therefore I do not ever recommend providing a breath sample unless required by court order. Below are just a few of the many reasons for the inaccuracies.

First, Breathalyzers operate under the assumption that the sample taken contains alcohol from the lungs. To calculate the amount of alcohol in the blood, the Breathalyzer's internal computer multiplies the amount in the breath sample. If the sample is not from the lungs but from the mouth, throat, or stomach, the amount of alcohol should not be multiplied, or the result will be falsely high. The failure of Breathalyzers to distinguish between alcohol coming from the lungs and alcohol which is already in the mouth or throat is a grave and common problem. A common source of mouth alcohol is acid reflux disease, which an estimated one-third of us suffer from occasionally.

Second, the computers inside Breathalyzers actually multiply the amount of alcohol in a DWI suspect's breath sample by 2,100 to get the blood-alcohol concentration. This is because it is programmed to assume that the suspect has 2,100 units of alcohol in his blood for every unit of alcohol in his breath. This is called the "partition ratio," but this ratio is only an average. Actual ratios vary from as low as 900-to-1 to as high as 3,500-to-1. If an individual's ratio is different, the blood-alcohol concentration result will be inaccurate.

A third common reason for inaccurate results is any change in a person's body temperature. If, because of illness, for example, the body temperature is elevated by only 1 degree Celsius, the 2,100-1 partition ratio used by Breathalyzers will be altered so as to produce a 7% higher test result.