After an arrest for DWI, many people have questions about whether the tests were necessary and what they mean. Here is some information about how the testing occurs and what you should know about it.
Often, the police will ask you to take two different breath tests when you are arrested for DWI. The first test, done on a portable breath test (PBT) machine, is merely used to see whether there is probable cause to arrest you for being intoxicated, as opposed to just consuming some alcohol. It is not very accurate, however, and it is not admissible in court to show that you are over the legal limit. The second breath test is usually done at the police station or jail on a stationary machine. That machine is often far more accurate and reliable. The results from that machine can be used in court to show that you are over the limit.
The accuracy of breath test varies. In fact, even if the results from the machine show that you are over the legal limit, if you are close to the threshold you may be able to argue that the general reliability of the machine creates a reasonable doubt that you were over the limit. In addition, there may be specific factors, such as health conditions or radio interference that can create inaccurate results. The testing procedure is complex, and it is important to talk with an expert to see if there is an opportunity in your case to challenge the results.
A common situation occurs when someone takes a PBT and later takes a breath test at the jail and the results between the two vary greatly. The divergent results (including even an increase of BAC) create confusion. As mentioned above, one factor may be the relative inaccuracy of the PBT compared with the dedicated testing unit. In addition, the divergent results may indicate that one reading was affected by external factors and did not produce a reliable result.
The best course of action if you are facing a DWI is to hire an experience DWI drunk driving attorney. An attorney will know the best methods to challenge the reliability of the breath test. Getting a breath test lowered or thrown out can result in dismissal of the case, a return of your vehicle, and reinstatement of your driver’s license. If you are facing a DWI and have further questions about how to challenge a breath test, call Minnesota DWI lawyer Eric Rice at (651) 998-9660 for a free consultation.