The legal battle over Vancouver's supervised injection site will continue in B.C.'s top court today.

Lawyers for the federal government are expected to seek to overturn a B.C. Supreme Court ruling last year that granted Insite, the Hastings Street injection facility, a constitutional exemption to stay open.

In effect, the ruling found elements of federal drug laws against possession and trafficking were unconstitutional where they concerned Insite users and staff, a decision that surprised even some Insite advocates.

But Insite isn't the only health facility that will be involved in this week's legal wrangling. The people behind the Dr. Peter Centre, which operates a much-less-publicized supervised-injection service as part of its care for people living with HIV/AIDS, will act as an intervener in the proceedings.

"We understand [the case] may have implications," said Maxine Davis, executive director of the Dr. Peter AIDS Foundation.

Davis said there are many health-care providers, eager to offer injection supervision but wary of the legal issues, who will watch the case intently.

"It will open the door to many other organized health-care organizations across the country feeling a lot more comfortable with moving forward."

Irwin Loy reports for Vancouver's 24 Hours.