Alcohol Breath Tests Are Often Unreliable - Don't Trust Them.
"Alcohol breath tests, a linchpin of the criminal justice system, are often unreliable, a Times investigation found. The devices, found in virtually every police station in America, generate skewed results with alarming frequency, even though they are marketed as precise.
The machines are sensitive scientific instruments, and in many cases they haven't been properly calibrated, yielding results that were at times 40 percent too high. Maintaining machines is up to police departments that sometimes have shoddy standards and lack expertise.
Technical experts have found serious programming mistakes in the machines' software. States have picked devices that their own experts didn't trust and have disabled safeguards meant to ensure the tests' accuracy.
The Times interviewed more than 100 lawyers, scientists, executives and police officers and reviewed tens of thousands of pages of court records, corporate filings, confidential emails and contracts. Together, they reveal the depth of a nationwide problem that has attracted only sporadic attention.
The consequences of the legal system's reliance on these tests are far-reaching. People are wrongfully convicted based on dubious evidence. Hundreds were never notified that their cases were built on faulty tests."