One of the most important duties law enforcement agencies have in North Carolina is removing intoxicated drivers from the highways. This means that officers tend to rush to some type of mechanical testing when a suspect could be impaired even when they could be under the influence of substances other than alcohol. All other types of DUI charges are based on blood samples for the most part in addition to officer testimony regarding what occurred or what was observed at the scene of the arrest. And while many prosecutors would like defendants to think that a breath analysis is an infallible evidence that can always be used against them in court, the truth is that there are a number of ways that a breath analysis can be questioned when a case is tried.
Expired machine calibration
Breathalyzers are required to be inspected on a regular basis to ensure they are producing accurate readings. Just as with any other mechanical device, machines can wear over time and begin producing inaccurate and sometimes enhanced results after so many suspects are tested using the device without servicing. Evidence that a Breathalyzer is unreliable is often used as part of a criminal defense strategy in questionable DUI cases, and it can be very successful when there is a lack of machine inspection records.
Lack of officer training
Another issue that can be presented in a criminal case argument is the lack of training for the officer conducting the test. All law enforcement agencies are required to train officers before putting them on duty without a partner, but jurisdictions that are short-staffed regularly put officers on duty before they are fully trained.
These are the two primary methods of contesting a Breathalyzer result when a case goes to court. However, there are also other defenses that can include inconsistent testimony from arresting officers and a lack of reasonable suspicion for the traffic stop itself.