Researchers say Breathalyzer tests fundamentally flawed

Researchers working in Washington state recently discovered fundamental flaws in the source code of a widely used Breathalyzer machine, Draeger’s “Alcotest” device. Two software engineers conducted the research at the behest of criminal defense attorneys after Washington adopted the Alcotest devices for all its state and local law enforcement agencies.

The engineers didn’t examine individual machines, instead focusing on the general source code and algorithms embedded in every device. They found huge holes in the consistency of data gathered, specifically when it comes to calibration of the devices, ambient temperature, fuel cell proficiency and breath temperature. Failing to account for deviation in any of those areas could produce widely varying – and thus unreliable – results.

Researchers also examined the Washington state calibration and maintenance protocol as part of the study to determine if it adequately accounted for issues inherent in the devices: the researchers found that these issues were, for the most part, ignored in the testing procedures. Furthermore, the state only requires that police agencies calibrate the devices annually, but the company itself recommends calibration every six months.

Though this research focused specifically on the Alcotest device and the testing protocol used in Washington state, the machines are used around the country, and many states have similar procedures. This could potentially mean that literally tens of thousands of breath testing machines are producing inaccurate results nationwide. Concurrent with those flawed results, tens of thousands of people might face unwarranted drunk driving charges.

A legal action filed by Draeger sought to prevent the release of these test results, with the company arguing that doing so violated a non-disclosure agreement meant to protect its proprietary source code. The researchers eventually settled the case, but, interestingly, Draeger didn’t challenge the results of the study per se, only the potential for the release of trade secrets and their intellectual property.

A challenge is pending in Washington regarding the validity of these machines and whether the state’s test procedures can adequately account for perceived flaws. The results of that case are still pending, but they could be precedent-setting for DUI defendants around the country.

If you or someone you love is facing a drunk driving charge, understand that the penalties and possible consequences are life-changing and far-reaching. You need an aggressive defense to prevent a conviction from affecting your life, your livelihood and your very freedom.

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