When a Wisconsin resident blows into a breathalyzer device for the purposes of establishing the level of alcohol in the person's blood, the person is trusting that the machine's reading will be fair and accurate. This can be misplaced trust when breathalyzers fail or are improperly maintained. As a result of an inaccurate breathalyzer reading, people may find themselves facing drunk driving charges even if they was sober at the time of their breathalyzer testing.
In essence, a breathalyzer test relies on the accuracy of a machine. Like any other machine, a breathalyzer test must be maintained and inspected to make sure that it is functioning properly. One of the most important maintenance steps in keeping a breathalyzer test accurate is calibration.
Calibration helps to guarantee that a machine's readings are accurate and consistent. Generally, a well-calibrated breathalyzer machine will give close if not exact readings for breaths given by the same subject within a very close proximity of time. If a breathalyzer cannot give sufficiently similar readings given equal testing subjects, it may not be properly calibrated.
A person facing drunk driving charges may be able to show that the breathalyzer device used during his traffic stop was either defective, poorly maintained or otherwise improperly administered. Law enforcement officials who use breathalyzers to collect evidence against suspected drunk drivers generally must be trained on the devices before they may use them. An insufficiently trained police officer may not use a breathalyzer correctly and a reading taken under such circumstances might be flawed.
Challenging a breathalyzer test can be part of a person's drunk driving defense strategy. Attorneys who practice DUI defense can help their clients learn about other possible defenses to challenge their charges. The incorrect reading of an improperly maintained breathalyzer device should not form the basis of an innocent party's wrongful drunk driving conviction.