How reliable are breathalyzers? Michigan state police take them offline

On Jan. 13, the Michigan state police announced that they would stop using all 203 breathalyzer machines they operate in stations around the state. The breath testing machines, Datamaster DMT evidential breath-alcohol testing machines, may have been improperly calibrated.

The agency said that contract employees of Intoximeters Inc., the state’s Datamaster vendor, may have committed fraud when certifying the accuracy of the machines.

The issue remains under investigation. However, the state police report that discrepancies occurred with at least 8 machines. They are currently recalibrating and recertifying all of the machines used around the state. No timeline was released for how long the recertification would take.

“Review of vendor records in the last two days has yielded additional discrepancies that may point to the potential for a more widespread issue with the way in which some instruments were being serviced,” said a spokesperson for the state police. “While the discrepancies do not directly impact or deal with the results of evidential breath tests, it is concerning that it appears as though some certification records have been falsified.”

These machines are found in police stations, as opposed to the roadside tests officers use to test drivers during traffic stops. Roadside breathalyzers are not guaranteed to be accurate and may be inadmissible or challenged in court. However, they do provide probable cause to arrest drivers and subject them to a more accurate test at the station.

According to MLive, the Michigan state police have issued a “stop order” on its $1.3-million contract with Intoximeters, citing “performance-related issues.” Unless the contract is reinstated, the state police will take over responsibility for calibrating the machines.

While the Datamaster DMTs are out of service, the state police said that they would subject drivers to blood-draw intoxication tests. Generally, however, drawing a person’s blood requires a warrant.

State police defend the Datamaster, doesn’t see need for conviction reviews

The spokesperson for the state police emphasized that “a properly calibrated and maintained Datamaster DMT is an extremely reliable instrument” but cited “egregious discrepancies” in the certification of the machines. However, he said that the discrepancies did not impact the results of the tests.

Without more specific information, determining whether the discrepancies did or did not impact the breath test results that were used to prosecute people in Michigan will have to wait to be seen. Considering that the certifications may have been falsified, however, it only seems reasonable to consider the evidence to be tainted and to review all cases in which a Datamaster DMT was used to gauge a driver’s blood alcohol content.

Skip to content