Detroit — Several medical marijuana caregivers and patients have filed a class-action lawsuit alleging the Michigan State Police crime lab intentionally misrepresented test results that expose thousands of people to possible felony charges.

The civil rights lawsuit, filed Tuesday in federal court in Detroit, alleges the state police acted in concert with the Prosecuting Attorneys Association of Michigan and other law-enforcement agencies, including the Oakland County Sheriff’s Office.

The lawsuit was triggered by an alleged ongoing policy by the state to produce inaccurate test results that show marijuana seized during criminal investigations contained the synthetic cannabinoid Tetrahydrocannabinol, or THC, which is responsible for marijuana’s psychoactive effects. THC, however, has little or no psychoactive effect when a marijuana plant is converted to an oil or edible, according to the lawsuit.

Under state law, possessing marijuana plant-based oils and edibles is a misdemeanor and Michigan residents with medical-marijuana licenses are legally allowed to possess them. It is a felony, however, to possess synthetic, laboratory-manufactured THC, according to state law.

The state crime lab has established a policy that potentially treats plant-based oils and edibles as synthetic THC, a policy that could expose people to a felony charge, according to the lawsuit.

“At least one reason for the policy change was to better establish probable cause to arrest medical marijuana patients, obtain forfeiture of their assets, charge them with crimes they did not commit, and to allow felony charges against others for what is at most a misdemeanor,” Farmington Hills lawyer Michael Komorn wrote in the lawsuit.

The state policy could effect thousands of Michigan citizens, including about 180,000 registered medical marijuana patients and about 33,000 registered caregivers, according to the lawsuit.

The plaintiffs want Chief U.S. District Judge Denise Page-Hood to revise the test results, block the state from issuing faulty reports in the future and appoint a crime-lab monitor.

A Michigan State Police spokeswoman declined comment Thursday. An Oakland County spokesman could not be reached for comment immediately Thursday.

The plaintiffs in the lawsuit include Brandon Shobe, an Oakland County resident and licensed medical-marijuana caregiver.

He was charged with possessing marijuana but faces the risk of a felony charge for possessing synthetic THC based on an inaccurate lab report, according to the lawsuit.

The plaintiffs obtained emails through the Freedom of Information Act that allegedly bolster their case. As early as 2013, the Prosecuting Attorneys Association of Michigan pressured the state crime lab to uniformly report edibles and oils as containing synthetic THC even though plant material was not visible, according to the lawsuit.

Michael Wendling, president of the prosecutor’s association, also could not be reached for comment Thursday.

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