Physical evidence, like chemical evidence, can help the state build a compelling criminal case. It is certainly more convincing than eyewitness testimony. When it comes to accusations of drunk driving, breath tests are the most common way for police officers to collect chemical evidence.

While most people would probably assume that someone who fails a breath test was over the legal limit, the truth is that breath testing sometimes implicates innocent people. There are numerous scenarios in which people could defend against impaired driving charges by challenging the accuracy of the breath test evidence used in the case against them. When is doing so a viable defense strategy?

When you have helpful medical or personal records

Have you recently bought one of those dieting breath tests to help you ensure you burn fat as frequently as possible? The daily results of using that test could help you show that it was your diet, not alcohol, that affected the chemical breath test you took during the traffic stop.

There could also be medical records, including evidence of certain prescriptions or a recent diagnosis, that will help you prevent an alternate explanation for why you failed the breath test. If there is a plausible explanation for why you failed the test, challenging it may be a reasonable choice.

When you know the results are wrong

There are many drivers who have no conclusive medical reason to challenge the breath test but still know the results were wrong. If you only had one drink or didn’t drink at all and failed a breath test, you may need to consider challenging the test results because of your firm belief in their inaccuracy.

While a police officer may not believe your claims that you drank nothing before the stop, knowing the results are wrong can be enough motivation to keep fighting and exonerate yourself.

When there were maintenance or calibration issues

Defendants facing drunk driving charges frequently want to see the state’s records of maintaining and calibrating the testing unit used during their arrest. Mistakes and gaps in those records might make the accuracy of the test questionable enough to prevent the results from serving as evidence in criminal proceedings.

Looking at all of your options, including challenging a breath test, can help you prove your innocence when accused of a drunk driving offense.