Ex-offenders on parole or supervised release in Minnesota can use medical marijuana under a new policy that took effect quietly this week, reflecting a philosophical change by new state leadership following a recent legal challenge.

The Minnesota Department of Corrections reversed course on Monday, allowing Minnesotans under supervision to show that they are on the state’s registry of patients approved for medical ­cannabis use.

Previously, Minnesotans on supervised release or parole were forbidden from possessing or using medical marijuana, even if they had a prescription and were on the state’s medical cannabis registry. Violators could be sent back to prison or receive more severe release conditions.

State corrections officials say the new policy conforms to a greater acceptance of medical marijuana.

“As the use of medical marijuana has grown and benefits everyone from veterans who have PTSD to those with chronic illness, it was beginning to become a greater issue for individuals who are being supervised,” said Sarah Walker, the state’s deputy commissioner in charge of community corrections. “Ultimately, our decision is pretty simple and makes sense: If you have a prescription from your doctor, just like with any other controlled substance that is prescribed, we are going to monitor it in the same way that we do those other drugs.”

The policy change will not apply retroactively and does not extend to Minnesotans on probation because those conditions are imposed by the courts, corrections officials said. But it now aligns the Corrections Department’s policy on medical cannabis with that for other prescription ­medications.

The shift also reflects a new focus under Walker, who took office on a mission to try to cut down on the number of Minnesotans sent back to prison on technical probation or supervised-release violations.

“The times that we are concerned about substance abuse is when there is a nexus between the substance abuse and the crime, and that just really isn’t the case with the use of medicinal marijuana,” Walker said.

The move is backed by Gov. Tim Walz, a Democrat who has sought to expand the state’s medical cannabis program. Kayla Castañeda, a Walz spokeswoman, described the change as a “fairness issue,” giving people under supervision access to medication like other Minnesotans suffering from the same conditions.

“The governor believes all people should have access to the health care they need, and that includes Minnesotans who have had contact with our criminal justice system,” Castañeda said.

Minnesotans must register with the state Department of Health to be eligible to receive medical cannabis if they suffer from a limited set of conditions including glaucoma, cancer, multiple sclerosis or intractable pain. The state has 15,758 patients active on the registry, according to the Health Department.

The corrections policy also comes amid a lawsuit filed against the department and a parole officer by a Chaska man who ran afoul of the previous restrictions even though he was on the state registry. Darrell Schmidt filed a lawsuit in Carver County District Court in January after his parole officer told him he would be sent back to prison if he tested positive after taking medical marijuana prescribed by his doctor.

According to the lawsuit, Schmidt had been diagnosed with depression, PTSD, insomnia and anxiety disorder. Anti-depressants caused intense intestinal problems that included bleeding. Attorneys for Schmidt, who has been on intensive supervised release since March 2017, said he was prescribed medical marijuana last year after a doctor ordered him to stop taking the anti-depressants. Barred from using marijuana, Schmidt’s weight dropped about 50 pounds because his anxiety and insomnia went unmedicated.

Patrick Casey, a Mankato attorney representing Schmidt, said his client was “elated” by this week’s policy change. Casey added that his office received more than 100 calls from people reporting similar experiences after Schmidt’s lawsuit became public earlier this year. Further litigation had been in the works before state officials changed the requirement.

Backers of the new policy say that the measure would also promote consistency across the state, where more than 111,000 Minnesotans are under supervision statewide.

“These people have paid their dues in the criminal justice system and should have access to something that the general public has access to that can benefit their health,” said Sen. Melisa Franzen, D-Edina, who has sponsored legislation to also legalize recreational medical marijuana use. Although that measure fell short in a Senate committee this session, Franzen called the shift by state corrections officials on medical cannabis “the new normal.”

Walker said the past corrections department policy had been applied unevenly in some counties. Schmidt’s lawsuit alleged that at least four people in neighboring McLeod County were able to take their prescribed medical marijuana.

“If these people are on parole and … if a component of what they’re dealing with is mental health related, I think it’s a good policy to treat them with the most effective drug and allow the doctors to have ultimate say,” Casey said. “And now that’s what we’ve got, and that’s what’s important.”