Improperly calibrated breath testing machines do occur

Most DUI arrests and convictions are based on the results of a breath testing machine such as the Intoximeter, Intoxilyzer, Alco-Sensor or Alcotest. As a result, attorneys defending DUI cases often question the accuracy and validity of the breath test. These machines can cause inaccurate results when they are used by untrained personnel, used improperly, or calibrated improperly, as well as in some other circumstances. When evidence suggests the machine may have been used or calibrated improperly, the test results may be found inadmissible.

A large-scale challenge to breath test results was recently brought in New Jersey after a former coordinator for the New Jersey Police Alcohol Drug Testing Unit was indicted. For approximately the past seven years, the indictment alleges, the man improperly performed the required calibrations of the Alcotest machines used in that state. He failed to use the proper thermometer for the temperature measurements required in the calibration, but he nevertheless certified that he had followed the proper procedures.

News of the indictment prompted one driver to try to withdraw her DUI guilty plea. As a result, a special appellate master was appointed to look into whether the man’s improper calibration had affected the test results and possibly the outcomes of DUI cases. In May, the special master issued a 198-page report concluding that the calibration errors completely undermined the reliability of the breath tests. In fact, if the Alcotest were miscalibrated by a single degree Celsius, an expert testified, the person’s blood-alcohol level could be off by as much as 7 percent.

The New Jersey Supreme Court, crediting the findings of the special master, has just determined unanimously that none of the miscalibrated Alcotest results are admissible in court. It vacated the driver’s conviction, as the case against her was based solely on the Alcotest results. It also ordered the state to notify every driver whose DUI case has now been called into question — an estimated 20,667 people. They will have the opportunity to challenge their convictions.

“Confidence in the reliability of instruments of technology used as evidence is of paramount importance,” wrote the court. “Unfortunately, alleged human failings have cast doubt on the calibration process.”

It’s true that our justice system depends on public confidence in the evidence used by our police. An error of this magnitude could easily undermine that confidence.

In this case, the deviation from the proper calibration technique was rather small, despite its outsized effect. The testing coordinator apparently substituted an approved temperature probe for an unapproved version that was made by the Alcotest device’s original manufacturer. Such mistakes could easily be happening in any jurisdiction.

If charged with DUI, you need an experienced attorney that can know what to challenge, when to challenge, and how to challenge breath or blood alcohol tests that may be questionable.

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