The fate of Vancouver's supervised drug-injection site hangs in the balance as the country's highest court is set to rule on whether it should be allowed to exist -- with or without Ottawa's blessing.

The Supreme Court of Canada's ruling on Friday will determine if Insite can operate without federal consent as a health-care facility under provincial jurisdiction, and if closing the site would violate the rights of drug addicts living in one of Canada's poorest neighbourhoods.

Right now, Insite is allowed to operate in the Downtown Eastside thanks to exemptions from federal drug laws that allow staff and clients to escape prosecution on drug possession and trafficking charges. A federal lawyer has said that the Conservative government hasn't decided whether it will extend that exemption.

Hoping to cut off the Tories at the pass, the group that operates the site using provincial funding asked a B.C. Supreme Court judge to allow it to stay open without the feds' consent. The Portland Hotel Society won that case, a decision that was upheld by the B.C. Court of Appeal, but the federal government continued to appeal the ruling.

Supporters, including the B.C. government, have pointed to peer-reviewed studies showing that Insite prevents overdose deaths, slows down the spread of diseases like HIV and hepatitis and curbs crime.

But the federal government says the safe-injection site just encourages addiction and runs counter to the Conservatives' tough-on-crime agenda.

Insite opened in 2003, making it the first supervised injection site in North America. The facility has 12 booths in its injection room and 30 beds in a detox and treatment centre upstairs. As many as 800 drug users visit the site each day.

With files from The Canadian Press