Correction: This story originally contained the incorrect amount of the annual contract with Toximeters Inc.

LANSING, MI -- Michigan state police are questioning the reliability of test results produced by breathalyzer machines used across the state.

The agency on Jan. 7 issued a “stop order” on a lucrative, 2018-signed contract currently worth nearly $1.3 million annually with St. Louis-based Intoximeters Inc., a company tasked with calibrating the state’s 203 DataMaster machines. DataMaster machines are used to determine a driver’s blood-alcohol level. While roadside breathalyzer tests are used to determine probable cause for a DUI arrest, the results are inadmissible in court.

Once suspects are booked during a DUI arrest, they’re administered a DataMaster breathalyzer test, the results of which are allowed for prosecution in court.

State police on Jan. 10 issued a memo to “criminal justice partners," including county prosecutors, notifying them that they ended the 20-year-plus contract with Intoximeters due to “performance-related” issues.

“Prosecutors with cases impacted by the contractor errors identified by MSP have already been notified,” the letter said. “However, out of an abundance of caution, we are examining all available data to determine if any additional tests are impacted by the contractor errors.”

State police in the letter said: “Because the integrity of the criminal justice process is of paramount importance, effective immediately, the MSP will assume the duties previously contracted to the aforementioned vendor."

State police now plan to service and calibrate the machines.

The nature and extent of the issue is unclear. State police representatives, as of Monday afternoon, had not responded to MLive requests for comment.

MLive reached out to multiple county prosecutors seeking comment and is awaiting response to questions posed to Intoximeters Inc.

“We will of course perform our due diligence," Wayne County Prosecutor Kym Worthy said. “It’s premature to comment further at this point.”

East Lansing-based DUI attorney Michael Nichols called the state’s targeted notice to the law enforcement community but not the general public a "lack of transparency.”

“We don’t know exactly what’s going on, but what I’ve observed over the years is an utter lack of consistency in following even the administrative rules that are established by the state police for verifying the accuracy of the instruments and demonstrating a scientific reliability ... ," Nichols said. “I’m not sure exactly how it got to this point or how pervasive it is, but I can tell you the contractors that were doing the work, I had a lot of concerns about their training and the work they were doing at police agencies around the state.”

State police memo on breathalyzer machines:

-- Gus Burns is the marijuana beat reporter for MLive. Contact him with questions, tips or comments at fburns@mlive.com or follow him on Twitter, @GusBurns. Read more from MLive about medical and recreational marijuana.

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