Broadly speaking, calibration means the comparison of an instrument’s measurement capability with a standard, in order to report, or eliminate by adjustment, any deviation in the accuracy of the instrument. A prime requirement for calibration is the availability of appropriate and accurate standards.
If a police officer stops you on suspicion of DUI/DWI, he or she will look for signs of intoxication. The next step is to subject you to a variety of field sobriety tests to determine if you are intoxicated or under the influence. You can refuse to take this test. If you refuse or you fail these tests, the officer will ask you to take a breath analyzer test. You can refuse the breath analyzer test but a refusal can result in the suspension of your driving privileges.
If the breath analyzer results indicate a breath alcohol concentration of 0.08 percent or more, you will have to take a chemical test. All states have per se DUI laws. Under these laws, if your blood alcohol concentration is 0.08 percent or over, you will be deemed intoxicated even if you are absolutely sober. The prosecution need not prove anything else. Whether you were in total control of the vehicle is irrelevant.
The calibration of the breath analyzer can affect the results of the breath analyzer test. If you can prove that the breath analyzer was not properly calibrated or maintained, the test result will not be considered as evidence against you.