Canada's Attorney General and Minister of Health were in a B.C. court Monday to appeal a lower court order that prevents Ottawa from shutting down Vancouver's controversial supervised-injection site.

The three-day B.C. Court of Appeal hearing is an attempt to overturn a B.C. Supreme Court decision issued last year that struck down parts of Canada's drug laws.

The ruling gave the federal government until June 30 of this year to bring the Controlled Drugs and Substances Act in line with the Charter of Rights and Freedoms.

It also gave Canada's only free-standing, supervised-injection site, known as Insite, an immediate constitutional exemption to stay open without a federal exemption from drug laws.

Federal lawyers will argue Justice Ian Pitfield wrongly turned a policy issue into a legal one and that preventing Ottawa from shutting down the clinic is akin to exempting alcoholics from drunk-driving laws.

Insite and its supporters have been battling the federal Conservative government, which was considering refusing the exemption that allows Insite to operate without breaking the law.