Saskatchewan's challenge of federal carbon tax in hands of Appeal court

Five Saskatchewan judges have reserved their decision on the constitutionality of a federally imposed carbon tax after two days of hearings in Regina.

Lawyers representing provincial governments, Indigenous groups and environmentalists from across Canada presented their cases before the Saskatchewan Court of Appeal.

Saskatchewan has asked the court to rule on whether a federal carbon tax is constitutional. The province contends such a levy is not because it wouldn't be evenly applied across all jurisdictions.

On Thursday, Ottawa and its supporters had their turn to argue. They said the federal government has the power to impose a carbon tax because Section 91 of the Constitution states it can pass laws "for peace, order and good government of Canada."

This power can be asserted because climate change and greenhouse gas emissions are a matter of a national concern, a lawyer for the Attorney General of Canada told the court.

Sharlene Telles-Langdon said carbon pollutants have "cumulative dimensions" and don't respect geographical boundaries once they are emitted into the atmosphere.

"One province's refusal or failure to sufficiently regulate greenhouse gas emissions impacts Canada as a whole," she said.

Telles-Langdon said Ottawa looks at greenhouse gases from a national perspective and that constitutionally provinces are unable to address Canada's overall emissions level.

"It's not necessary for each of the systems in each province to be the same to achieve the objectives of the legislation or to address the matter of national concern," Telles-Langdon said.

"What is necessary is that a pricing system applies throughout Canada."

A lawyer for British Columbia's attorney general, intervening on Ottawa's side, said emissions affect other provinces and the federal government is acting on a duty to protect these interests.

"The fate of the planet is involved so it's something that the federal government should be given leeway to do," said Gareth Morley.

In response, Saskatchewan's legal counsel argued that Ottawa is seeking "exclusive federal jurisdiction" to deal with greenhouse gas emissions because these pollutants are a part of daily life.

"This type of jurisdiction would give the federal government the authorization to pass legislation that would eviscerate provincial powers," Mitch McAdam said.

He closed the provincial government's case by reiterating his opening statement made Wednesday that the issue before the court is the divisions of power, not saving the planet from climate change.

Saskatchewan's anti-carbon tax allies, such as New Brunswick and Ontario, earlier argued that Ottawa is overreaching into provincial jurisdiction and in doing so is threatening the balance of federalism.

Saskatchewan, New Brunswick, Ontario and Manitoba do not have their own carbon-pricing plan and will be subject to Ottawa's fuel tax starting in April.

The federal government's carbon price starts at a minimum at $20 a tonne and is to rise $10 each year until 2022.