Few interactions with law enforcement are more stressful than those that occur after a night on the town. While abstaining from driving after you have been drinking is an effective way to avoid a driving while intoxicated charge, you must realize that the tests officers use to measure blood alcohol concentration do not always produce reliable results.
There are a variety of reasons a breath test may give a false-positive reading. For example, you may have certain medical conditions that trick the test into thinking your BAC is above the 0.08% legal limit when it is in fact not. Still, operator error may also cause a breath test device to give unreliable results.
Like virtually all machines, breath tests usually require calibration. Officers receive training on how to keep the breath tests they use in good shape. If the officer who pulled over your vehicle failed to correctly calibrate the breath test, though, the reading may not be correct.
While breath tests are legal in Minnesota, they should be accurate. Naturally, for breath tests to produce reliable results, officers must use them correctly. They must also give you instructions to avoid errors. As you may suspect, if an officer administers the test incorrectly or does not coach you through the process, the results may be inaccurate.
Incorrectly storing a breath test device may cause it to malfunction. Before accepting the reading as correct, you may want to investigate whether an officer stored the test in a hot vehicle or otherwise failed to store it properly.
Technology advances quickly. As breath test device manufacturers work to improve their products, they may make previous devices obsolete. Further, as a breath test ages, it may become less reliable. Even though officers should replace devices that are no longer giving accurate results, this does not always happen. Accordingly, requesting details about both the model and age of the breath test may be worthwhile in building your defense strategy.