Toronto — A group of seriously ill people has won the latest battle in an ongoing war with Ottawa over a scheme to permit the use of medical marijuana the patients say violates their constitutional rights.

An Ontario judge agreed Thursday that the federal government's Medical Marijuana Access Regulations are unconstitutional because they prevent more deserving people from exemption than they permit.

The ruling from Ontario's Superior Court is binding on lower courts, subject to an appeal, and will likely wreak further havoc on the laws in Canada that make possession of marijuana illegal, said lawyer Alan Young.

"We sued the government, saying their regulatory regime for medical people was unsound," Mr. Young said. "The judge agreed, saying they have six months to address it or they lose the law."

The regulations give eligible people an exemption from provisions of the Controlled Drugs and Substances Act, the law which makes possession of pot illegal for everyone else.

Unless Ottawa appeals the ruling or comes up with a new medical-marijuana regime within six months, that law will fall, Mr. Young said.

"The law will be dead in Ontario," he said. "There will be no further questions about that."

Mr. Young argued in court last year that the regulations demand medical declarations that few doctors are willing to provide given the legal consequences.

They also make it impossible for a doctor to recommend a dosage, since the drug remains unregulated in Canada.

Even those who do win a legal exemption — more than 300 people in Canada are currently permitted by Ottawa to smoke pot for medical reasons — are forced to break the law, resorting to black-market weed because the government is dragging its heels on efforts to cultivate a pure supply for clinical trial.

There were seven marijuana consumers included in Mr. Young's group of applicants, along with a caregiver, the Toronto Compassion Centre. Three other applicants are also participating in the hearings.

There was no immediate word Thursday on whether the ruling forces the government to make available the marijuana it grew in a Manitoba mineshaft under a $5.7-million contract for clinical trials.

Federal Health Minister Anne McLellan had refused to allow the marijuana to be distributed because she says it simply isn't pure enough.