If you take a breath test after a traffic stop and your blood alcohol concentration (BAC) is over the legal limit, the officer is going to arrest you on suspicion of impaired driving. The breath test used by the police department is likely admissible as evidence in court. Courts are also allowed to presume impairment for anyone who breaks the legal limit.
Because of this connection, people sometimes assume that failing a breath test guarantees that they will later be convicted in court. But the truth is that the test itself could be wrong, invalidating the evidence and preventing a conviction. It’s important to understand how this may happen.
Mistakes during the test
One example is if the police officer themselves made mistakes while they were giving you that test. Maybe they made errors and you felt like they didn’t know how to use the test properly. Maybe they were never given any training by the department.
Calibration issues
Another potential problem is when the breath test hasn’t been calibrated or when the calibration hasn’t been done recently enough. If police officers neglect breath test devices, how can they be sure that the results are accurate?
Other influences on the test results
Finally, even if the test results were technically accurate, they could’ve been swayed by outside influences. If you burped during the test, for example, this can increase the alcohol content in your mouth. That could give you a reading that is over the legal limit – even though your actual blood alcohol concentration is much lower.
These are just a few issues to keep in mind. If you are facing criminal charges, be sure you know what defense options you have.