The country's top court has decided not to hear the City of Victoria's appeal in its fight to ban single-use plastic bags, in the latest blow to the municipality in a years-long battle over which governments have the power to regulate sustainability issues.

The Supreme Court of Canada declined to hear Victoria's case in a decision Thursday morning. As is customary, the court did not give reasons for the ruling.

"While we are disappointed that the Supreme Court of Canada will not hear the case, there are other avenues for us to achieve our goals of eliminating plastic checkout bags and reducing waste in our community," Mayor Lisa Helps wrote in a statement released after the court's decision was posted.

The city's ban comes in the form of a bylaw forbidding grocery stores from offering or selling plastic bags to shoppers. Stores could still offer paper bags or reusable bags for a cost, if customers asked. Councillors first approved the bylaw in December 2017.

The Canadian Plastic Bag Association filed a challenge in B.C. Supreme Court within a year, claiming the city went beyond its authority to enact the rule. The association said the city was required to have the bylaw approved at a provincial level before rolling it out.

The court rejected the association's argument, but the B.C. Appeal Court overturned the decision on July 11, 2019. In handing the association its first victory, the appeal court found the city's ban was based on environmental concerns — which fall under the jurisdiction of the province and the Ministry of Environment.

Victoria Mayor Lisa Helps, pictured in August 2019. Helps says her city isn't giving up its fight to enact a ban on plastic bags in the wake of Thursday's decision by the Supreme Court of Canada. (Jill English/CBC)

Bylaw set aside

The bylaw hasn't been in effect since the summer ruling, but the city said "most" local businesses in the provincial capital have been operating as though the ban is still active anyway — "a testament to the wide community support of the bylaw," Helps said Thursday.

The statement said the community's efforts have taken more than 17 million plastic bags out of landfills.

The mayor said the city hoped to appeal the "very restrictive" appeal court ruling with the Supreme Court of Canada in order to "clarify a municipal government's power to regulate unsustainable business practices that negatively impact the community."

A shopper puts peas into a cloth bag while grocery shopping on April 6, 2018. The City of Victoria said many local businesses have honoured a ban on plastic bags in the city, even though the bylaw was set aside in July 2019. (Vincent West/REUTERS)

Appeals to the top court are not automatic. The court only agrees to hear cases involving significant legal issues of national importance.

The city argued the precedent set by B.C.'s appeals court could potentially affect other municipal bylaws well beyond Victoria, across B.C. and in other provinces with similar municipal legislation.

The Canadian Plastic Bag Association is now known as the Canadian Plastics Industry Association. It has said the arguments for banning plastic bags don't take into account that plastic bags are often reused and use less energy and water to make than an alternative like a cotton bag.

Craig Foster, a sustainability consultant speaking for the association, said Thursday's ruling was welcome news after months spent in court.

"I'm glad it's over," Foster said. "It really is a decision that says the province is the one who should be making these kinds of decisions."

The statement from the city did not specify its next steps. The mayor is expected to speak to reporters later Thursday.

At least 20 other B.C. municipalities moving to implement bans on plastic bags will have been following the capital's example closely, using it as a case study while they draft their own legislation.

Many municipal governments are also looking to the province for leadership on the issue.

The provincial government is currently reviewing single-use plastics to come up with a potential provincewide ban. Ottawa has committed to banning such items across the country as early as 2021.