People sometimes make the mistake of thinking that a breath test is solid proof of a DUI that can't be challenged. They look strictly at the numbers, determining that a driver who blew over 0.08 must have been legally too drunk to drive.
However, the truth is that no device is flawless 100 percent of the time. A breath test can be wrong, and these tests have delivered false readings in the past. So, how do you show that the test results should not be used as evidence in court?
First off, you may be able to show that the police department simply didn't calibrate the device properly -- or often enough. It's important to know that regular maintenance may be required to keep the test working correctly, along with calibrations done on a set schedule. If the police were supposed to calibrate the device every three months, for example, but they hadn't done it in two years, you could contest that there's no way to know if the reading it got was right or not.
As you can see, this doesn't prove you were sober, but that's not what you have to do. You just need to show that the evidence presented can't demonstration whether you were sober or not, and the key may lie in examining those calibration records.
Another thing to consider is the results of the test itself. If you took the test multiple times and the results were massively different each time, that could indicate that there was a serious problem. For example, you may have blown a 0.02 the first time, then blown a 0.09 the second time and been arrested. You could contest that these results, taken just minutes apart, are so completely different that it's clear the device was providing inaccurate data.
You do have defense options in court in North Carolina, as this shows, even when the evidence seems stacked against you. Be sure you know what they are.
Source: FindLaw, "Breathalyzer Calibration," accessed Aug. 05, 2016