A New York Times article by Stacey Cowley and Jessica Silver-Greenberg confirms what Massachusetts OUI lawyers and defenses attorneys everywhere have been arguing for years, that breath test machine are often inaccurate and unreliable. The Times found that these machines, a “linchpin of the criminal justice system,” are, at best, unreliable. In its investigation, The New York Times found evidence that the machines’ internal code was flawed, creating rounding errors that pushed results over the legal limit – 0.08 or higher. Further, the machines are required to be calibrated; often, this never happened. In some cases, calibration records were completely faked.
Defective Design = Reasonable Doubt: Experts in Washington find numerous problems with breath test machines and results
At least one manufacturer – Dräger, a German company – has repeatedly blocked efforts to review their software code as well as any reports regarding the machines. A judge in Washington granted a request from defense lawyers to have the code evaluated by an outside expert. Robert Walker and Falcon Momot, described as “veteran programmers and security experts,” wrote a report titled, “Defective Design = Reasonable Doubt.” They shared the report with defense attorneys at a conference. But Dräger demanded that the report be destroyed by them as well as anyone with a copy. The New York Times was able to obtain a copy that had escaped destruction; it stated that Dräger’s Alcotest 9510 machine was “not a sophisticated scientific measurement instrument” and that it did “not adhere to even basic standards of measurement.” Instead, the machine rounded up at least some of the results. Further, these machines did not account for the temperature of the person’s breath. Samples above 93.2 degrees (as most breath samples are) often cause inaccurately high readings. This is because Washington opted not to pay the extra money for a sensor that would measure breath temperature and allow the machine’s software to account for it. Washington was not alone. Massachusetts has not paid for the additional feature to account for breath temperature, only the State of Alabama has this added feature for enhanced accuracy of results.