In a previous post, we spoke about a case in which a Texas judge dismissed drunken driving charges against a woman who had registered a particularly high blood alcohol level on the basis that she has a condition in which her digestive tract brews alcohol and causes an elevated concentration of alcohol in her blood as a result.
The case is a good, if rarely occurring, example of the fact that blood alcohol testing must be carefully scrutinized rather than taken at face value. The fact is that there are various factors that can impact blood alcohol testing, particularly when breath testing is used.
According to one company that sells breath testing devices, test results can be affected not only by foreign substances in the a driver’s mouth, such as mouthwashes, breath fresheners, and medicines, but also environmental factors such as paint and varnish fumes, as well as plastics and adhesives. Depending on the circumstances of the case, the presence of foreign substances or environmental factors can call into question the results of a breath test.
In addition, there are use-related factors to consider when evaluating the accuracy of breath testing. These include glitches in the software of breath testing devices, user errors, and proper calibration and maintenance of breath testing devices. In addition, there is the fact that breath tests usually have to be performed multiple times to produce accurate results rather than simply one time. Police agencies are supposed to ensure their devices are properly maintained and that officers are trained to correctly use them, but the evidence does not always support these points.
An experienced DWI attorney will be sure to explore these issues thoroughly when building an effective DWI defense case.