Four years after voters legalized medical marijuana in Massachusetts, the Department of Public Health’s failure to implement a portion of the medicinal law has created a confusing environment in which police still arrest patients for growing marijuana or seize their plants, according to lawyers and advocates.

Under the law, the state was supposed to issue hardship cultivation registration cards to patients who, for financial or health reasons, could not regularly access their medicine from a dispensary.

But DPH has not issued any hardship registrations. And while the state issued a “Medical Marijuana Law Enforcement Guidance” document to notify police that it is legal for patients to grow their own plants, within certain limits, the document is not legally binding and police forces have used different interpretations of it.

“We at the (Massachusetts Patient Advocacy Alliance) hear from patients all the time who are growing in their houses in locked, secure facilities, who have the police come in and say ‘you don’t have your hardship license’ and take their plants,” said Michael Latulippe, development director of the MPAA, which helped pass the medical marijuana law.

A similar incident hit headlines last week when State Police and the U.S. Army National Guard raided an 81-year-old Amherst woman’s garden to seize one marijuana plant. That woman, Peg Holcomb, did not have a medical marijuana card, although she did use the plant to treat conditions like insomnia and glaucoma.

On Sept. 13, State Police also raided the Wendell garden of Patti Scutari and Francesco “Apollo” Compagnone and seized 10 marijuana plants. Both Scutari and Compagnone were certified medical marijuana patients who had been told by their doctor that they were allowed to grow the plants in a secure space so long as it was not visible to the public.

Attorneys recommend medical marijuana patients grow their plants indoors, but many remain confused about whether the plants can be grown outside so long as they are secured.

“I said (to the State Police trooper) ‘give us two, three days and we’ll move them inside,” Scutari said. “They had fencing cages around them so it would be very difficult for people to come and steal them.”

The raids that seized Holcomb’s and Scutari’s plants were conducted by State Police and the U.S. Army National Guard under a Domestic Cannabis Eradication/Suppression Program grant from the U.S. Drug Enforcement Administration.

In 2014 and 2015, law enforcement officers working under the grant arrested eight people and eradicated 227 marijuana plants, according to DEA records. All of those were reported to be outside.

It was not clear what the charges were on the arrests, and law enforcement officials did not return requests for comment.

If the DPH issued hardship registrations it would give patients a legal document to show police and landlords that they are allowed to grow marijuana plants advocates say, but that has not happened.

The DPH also did not return a request for comment.

“Part of the problem with the lack of the hardship program’s operational capacity is it leaves these people open to the State Police, who are acting like it’s the height of the Reagan years,” said Michael Cutler, a Boston-based attorney who specializes in marijuana laws.

The problem is exacerbated by the slow rollout of medical marijuana dispensaries. The first dispensary opened in Salem in June of last year. Seven more have opened since, but the medical marijuana law called for 35.

With such limited supply, patients like Mark Ward, of Lowell, hoped to rely on homegrown plants. But because he cannot prove to his landlord that he is legally allowed to cultivate marijuana, Ward has not been able to do so.

“I’m in pain every day and I can’t grow my own medication — a plant that I’m legally able to grow,” Ward said.

He is left waiting for the state to fulfill its promise to fully implement the law and wondering when he will find out how he can grow his marijuana without risking a police seizure.

“When is that time?” Ward said “Are you going to tell me when it’s that time, or am I going to find out when somebody comes knocking at my door?”

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