An institutional dispute between the Supreme Court of Canada and the Conservative government reached a new plateau on Thursday after the court said medical-marijuana users have the right to consume the drug in ways other than smoking – such as cookies, lip balm or lozenges.

Health Minister Rona Ambrose, speaking to reporters, said she is "outraged" by the ruling, and she accused the Supreme Court of steering young people toward marijuana use in the same fashion as Liberal Leader Justin Trudeau, who has proposed decriminalizing the drug. She said it should not be judges but medical experts at Health Canada who set the rules.

"This expansion of a pre-existing court-imposed program to now include cookies and candies makes marijuana more attractive and accessible to youth and reflects Justin Trudeau's campaign to legalize and normalize marijuana," she said in a prepared statement.

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There was no reference to candies in the Supreme Court ruling.

Ms. Ambrose's mention of a pre-existing court-imposed program refers to lower-court decisions establishing the right of chronically ill people to use marijuana for medical purposes.

In no other Supreme Court ruling of the past 18 months – including an end to assisted suicide, the striking down of prostitution laws and an unequivocal no to the government's plans for Senate reform – has the government responded with the strong and swift criticisms that followed Thursday's marijuana ruling. Last spring, after the government lost five major cases in six weeks, Prime Minister Stephen Harper publicly assailed the integrity of Chief Justice Beverley McLachlin.

The 7-0 ruling on medical marijuana offered the biggest rejection of the government's stated war on drugs since 2011, when the Supreme Court said unanimously that federal authorities had no right to close a Vancouver clinic at which drug addicts could inject illegal drugs under medical supervision.

Several other marijuana-related cases are before Canadian courts, including one on the right of medical users to grow their own plants.

The Supreme Court said on Thursday that the federal law setting out how medical marijuana is used is arbitrary and runs counter to the government's stated purpose of protecting health. And the ruling was signed by "the court" – a signal of the judges' unity on the subject.

Citing evidence accepted by the trial judge who first heard the case – evidence from medical experts and medicinal users – the court said that by insisting on only the smokable form of marijuana, the government was subjecting ill people to the risk of cancer and bronchial infections and precluding the possibility of choosing a more effective treatment.

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The case involved Owen Smith of Victoria, who worked for a medical "club" that sold marijuana to those who use it for medicinal purposes. In 2009, police, responding to a complaint about an offensive smell in an apartment unit, found 211 marijuana cookies and other products. Mr. Smith was charged with possession of marijuana and possession for the purpose of trafficking.

The trial judge ruled that the law limiting medical users to smoking the dried form of cannabis violated their right to liberty. Two of three judges on the B.C. Court of Appeal agreed, and the federal government appealed.

Jason Gratl, a lawyer representing the British Columbia Civil Liberties Association, which intervened at the Supreme Court, said the ruling sends a message that the courts will not uphold arbitrary laws that have no basis in science.

"The argument that medical marijuana must be smoked is, after all, ideological, counterproductive in terms of health and lacking any factual foundation," he said in an interview.

Greg Engel, CEO of licensed producer Tilray, said his company has been interested in researching edible products for some time, but he doesn't expect the government to allow commercial growers to sell different forms of cannabis until lengthy clinical trials are completed that determine appropriate dosages and areas of treatments.

"From our perspective it doesn't change anything in terms of what we're able to produce and sell," he said.

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Kirk Tousaw, a lawyer who represented Mr. Smith, called the ruling "a massive step forward for patient rights in this country."

Ottawa brought in regulations in 2013 restricting the growing of marijuana to government-licensed producers.

Adam Szweras, a founder of Nutritional High International Inc., which sells its technology for edible marijuana products in the United States, said his company will be able to work with licensed producers in Canada now. "We'll seek to work with licensed producers to make our products available throughout the market."

William Trudell, chair of the Canadian Council of Criminal Defence Lawyers, said Ms. Ambrose's use of the word "outraged" was disrespectful. "The open season on the judiciary by this government when their legal arguments fail is foreign to Canadian values," he said.

Editor's note: An earlier version of this article incorrectly said Tilray has been researching edible products. In fact, it has been interested in researching such products.