Michigan’s attorney general says law enforcement agencies that seize medical marijuana from licensed patients or caregivers don’t have to return the legal medicine when the patient or caregiver is released from custody.

Attorney General Bill Schuette, a vocal critic of Michigan’s marijuana law, issued his opinion late Thursday.

“By returning marijuana to a registered patient or caregiver, a law enforcement officer is exposing himself or herself to potential criminal and civil penalties under the (federal law) for the distribution of marijuana or for aiding or abetting the possession or distribution of marijuana,” the opinion stated. Schuette says the federal law overrides the state law and doesn’t allow police officers to return the drug once seized.

It is the latest move by Schuette, a former head of an anti-marijuana group. He campaigned against the issue before voter approval while he was an appellate judge. Since he’s been attorney general, he filed several briefs supporting prosecutors interpreting the act in a way that voters never intended.

In his opinion, Schuette said, “The people of this State, even in the exercise of their constitutional right to initiate legislation, cannot require law enforcement to violate federal law by mandating the return of marihuana to registered patients or caregivers.”

An opinion from the attorney general is generally considered binding legal opinion, especially on state agencies like the Michigan State Police, unless and until it is rejected by a judge. The opinion was in response to a request by state Rep. Kevin Cotter, R-Mt. Pleasant, who asked if law enforcement had to return marijuana to patients following arrest or detainment.

Medical marijuana advocates said police in Michigan have routinely returned marijuana to patients who have been temporarily detained since the state law went into effect. In fact, the medical marijuana statute explicitly bars the seizure of marijuana and marijuana paraphernalia from a licensed patient.

Michigan has about 100,000 people registered to use marijuana for medical reasons. Schuette’s opinion does not authorize police to prosecute patients for marijuana possession.