In our last post, we began speaking about the potential impact of blood alcohol concentration testing in drunk-driving cases. As we noted, blood alcohol testing can impact not only criminal penalties, but also administrative penalties, so it is important for defendants to work with an experienced criminal defense attorney to scrutinize questionable alcohol test results.
There are, of course, different ways that law enforcement officials measure blood alcohol concentration. The most commonly used method is to do breath-testing. Not only do police officers routinely conduct preliminary breath testing on the roadside prior to arrest, but they also conduct breath testing with more accurate machines after an arrest is made. The purpose of preliminary breath testing is to gather evidence of probable cause, whereas the purpose of post-arrest breath testing is to obtain a more accurate test result that can be used in court.
Breath testing machines, in order to produce results that are considered accurate in court, must be properly maintained by trained personnel and routinely tested for their accuracy. If prosecutors cannot demonstrate that breath testing devices and machines are properly maintained, the evidentiary value of test results decreases dramatically and can rightly be called into question by the defense.
When police departments fail, for whatever reason, to have-breath testing devices properly maintained, the right thing to do is to put those devices out of use until they may be routinely tested for accuracy. In our next post, we’ll look at a situation out in Washington D.C. where this very thing has happened, and we’ll speak a bit about situations where police fail to take responsibility for their failure to maintain these devices.