The invention of the Breathalyzer and similar devices revolutionized enforcement of drunk driving laws. For the first time, police and prosecutors could say they had an objective, convenient way to measure a suspect’s blood-alcohol content in a moment. Often, the result of the breath test is the key piece of evidence against a person put on trial for DUI, comparable only to the testimony of the arresting officer.
Many people assume that if the Breathalyzer said the defendant was over the legal limit, it must be true. The truth is, these devices are not infallible, and inflated test results happen. Without the benefit of a vigorous, thorough defense, many people in Michigan are convicted of drinking and driving, or pressured into pleading guilty, when they had not violated the law.