If you're given a breath test after a traffic stop and it comes in at .09, you may be arrested on allegations that you were driving while intoxicated.
However, it's important for police to know that the breath test device, often called a Breathalyzer, is accurate. If it hasn't been calibrated properly, how can they actually know you were over the legal limit?
One way that the police are supposed to test these devices is by making sure that they yield consistent results. If two tests are given in a short span of time, to the same subject, the results should be no more than .02 apart.
After all, wildly different results call all other results into question. If it says your blood alcohol concentration (BAC) is .17 one minute and .04 the next, something is wrong. Your BAC can't change that fast. It takes hours for it to drop back to 0.00. The results should be close.
If they're not, it could be an indicator that police have not been checking and maintaining the units properly. They're supposed to have a schedule and stick to it. All it takes is one officer to ignore the schedule for an innocent person to be arrested.
Additionally, officers have to be trained to use breath test devices. If the officer was never told how to calibrate the unit, that's a serious problem. This lack of simple training could mean all results from that device can't be trusted until a real calibration is done.
Do you think the breath test was wrong? Make sure you know your rights and exactly how to proceed.
Source: FindLaw, "Breathalyzer Calibration," accessed Jan. 17, 2018