British Columbia does not have to hand over the detailed health-care records of millions of people to tobacco company Philip Morris International, says Canada's top court.

Friday morning's unanimous Supreme Court decision clears a hurdle in the province's quest to sue cigarette companies for billions of dollars in health-care costs.

Writing for the court, Justice Russell Brown found the health care databases Philip Morris wanted contained information about individuals whose privacy the province is obligated to protect.

The ruling is the latest chapter in B.C.'s legal fight to force cigarette makers like Philip Morris International to compensate the province for the cost of treating tobacco-related illnesses — a battle that started in the late 1990s.

Philip Morris International argued it needed unfettered access to individuals' health data to defend itself in court.

The province's lawyers argued that releasing individuals' health information — even anonymously — could violate privacy laws.

B.C. pointed to a provision in its Tobacco Damages and Health Care Costs Recovery Act that specifically covers privacy.

Last year, the B.C. Court of Appeal upheld a lower court's decision that agreed with the company, and ruled that to ensure a fair trial, the province needed to hand over the patient data.

It also ruled there was no real threat of identifying individuals.

The Supreme Court disagreed.

"To bring it down to a nutshell, it means health data is private data," said David Fewer, director of the Samuelson-Glushko Canadian Internet Policy and Public Interest Clinic out of the University of Ottawa. His group had intervener status in the case.

Documents can't be shared, ruling says

Brown wrote that the lower courts focused on the relevance of the databases rather than the content of the information. He said documents related to individual health-care benefits cannot be shared, even if identifying information is removed.

British Columbia did offer tobacco companies access to Statistics Canada data, under strict controls, but Philip Morris refused.

Brown said Philip Morris could ask for a "statistically meaningful sample."

Fewer said that could involve Philip Morris sending a researcher to a facility to review patient information.

The province was pleased with the result, but a spokesperson said this win is just one piece of a larger story.

"It is a significant portion, but not the full case. The security and confidentiality of health data was one of our primary considerations in pursuing this appeal," said Laura Heinze, a spokesperson for the Ministry of Health.

"Holding tobacco companies accountable is a priority for the province and we are doing everything we can to ensure a successful outcome on behalf of British Columbians."

Rothmans Benson & Hedges (RBH), Philip Morris International's affiliate in Canada, said it doesn't see Friday's ruling as a total loss.

"Although the Supreme Court disagreed with the B.C. courts that the anonymized databases should be produced now, the Supreme Court acknowledged that RBH and the other defendants are still entitled to production of the databases if any of B.C.'s expert witnesses rely on them, and to apply for production of a statistically meaningful sample of the databases and other documents," wrote spokesperson Sarah Tratt in an email.

B.C. Information and Privacy Commissioner Michael McEvoy said the ruling comes at a time when Canadians' data is becoming more valuable, both commercially and as a research tool. His office had intervener status in the case.

"We can't ignore the fact that this ruling comes in a context in which there is a far greater awareness about privacy, privacy rights, the use of data, particularly sensitive data," he said.

"You can't think of data that is any more sensitive than that which is about somebody's health, whether it's a person's test (or) their interactions with their doctors."

B.C. was the first province to start the litigation process, but every other province has since launched similar cost-recovery cases against the tobacco industry. New Brunswick's case will go to trial in 2019.

Collectively, the provinces are seeking about $120 billion.

Rob Cunningham, a lawyer with the Canadian Cancer Society, said today's decision is an important preliminary defeat which could affect the other provinces' cases as well.

"The objective of the tobacco industry is to delay the start of this trial. They don't want to have to pay tens of billions of dollars in damages," he said.

"It is really important that provinces move aggressively to bring their cases to trial. It has taken too long."

British Columbia's case against 13 tobacco companies has been at the examination-for-discovery phase since early 2018. That pre-trial portion is expected to run through the first quarter of 2019.

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