Michigan State Police said Wednesday that it's reworking its marijuana toxicology testing process after temporarily halting it due to potentially inaccurate results.
In a statement, MSP Director Col. Joe Gasper said THC toxicology results may have misidentified the substance in samples containing CBD. According to Gasper, a technical issue resulted in CBD being converted into THC.
THC is the primary psychoactive compound in marijuana.
State police said the issue may affect 3,250 lab reports and court cases as far back as March 28, 2019.
While THC and CBD are both legal in the state, it’s illegal to drive under the influence of THC.
The department said it notified the Prosecuting Attorneys Association of Michigan on August 25 and has requested an independent review from its accrediting body, the American National Standards Institute's National Accreditation Board.
Marquette County Prosecutor Matt Wiese said prosecutors were told by MSP that it will take about six weeks for the department to develop new testing procedures. Wiese serves on Governor Gretchen Whitmer's Task Force on Forensic Science, which did not participate in the evaluation of the state's testing method.
Wiese said current cases using results will be delayed until a new procedure is found, and pending cases will be reviewed on a case by case basis.
“On quite a few of the cases you may have a combination of THC, alcohol, cocaine, or methamphetamine,” he said. “We don’t rely upon just the drug testing exclusively; we also have to show signs of impairment when we go to court.”
Wiese said he doesn’t expect delays to be as long as those seen during the coronavirus pandemic, and he doesn’t foresee a large number of past cases being reopened.
“In discussions with other prosecuting attorneys, we were generally hard-pressed to remember any single case where we just relied upon operating under the influence of THC. There’s almost always some other aggravating factor that goes along with it,” Wiese said.
But Wiese said stakeholders, defense attorneys, and defense associations across the state have been notified of potential inaccuracies in THC reports and are welcome to have their cases reviewed.
“My fellow prosecutors have been fully disclosed on this issue and want to make sure that we address it so people have confidence that our system is fair,” he said.
Meanwhile, Michigan State Police said it's started validating new methods to distinguish CBD from THC and has halted the disposal of blood samples for possible reanalysis.
The department said it's also begun the process of establishing a contract with a private lab to process samples.
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