Those involved in marketing breathalyzer machines in Pennsylvania tout the devices’ precision to the third decimal place. The machines are ubiquitous; nearly every law enforcement station in the United States has one. When a breathalyzer indicates that a driver’s blood alcohol concentration is above the legal limit, a DUI conviction usually follows. 

However, the New York Times recently conducted an investigation demonstrating the alarming frequency with which breathalyzer machines yield inaccurate results. Sometimes the results can skew too high, which could mean that innocent drivers end up convicted on the basis of faulty evidence. 

There are a number of reasons why breathalyzers may yield inaccurate results. Most of them fall into one of two categories: lack of government oversight and human error. Breathalyzers come with safeguards in place to ensure accuracy, but the states sometimes disable these. Analysis of the machines has sometimes uncovered serious mistakes in the programming. 

The responsibility for maintaining the machines often falls to individual law enforcement departments in each city. The departments may not have the necessary expertise to perform the task. Whether from ignorance or negligence, they may not use the correct products to clean the machines. This can cause test results to become warped. Sometimes the issue is present from the beginning. Breathalyzers require careful calibration to perform properly. When they do not receive it, the results can be too high by up to 40%. 

Many people may suffer unnecessarily because of law enforcement’s reliance on a technology that evidence suggests is not consistently accurate. People questioning the accuracy of a breathalyzer test may find it helpful to contact an attorney.