Sask.'s constitutional court challenge of federal carbon tax begins today

Dozens of lawyers will pack into a Regina courtroom this week to argue whether the federal government can impose a carbon tax on the provinces.

Sask., Ont., N.B. arguing against a federal carbon policy while Ottawa and B.C. argue for

Lawyers representing the position of Saskatchewan Premier Scott Moe's government are facing off with lawyers representing Prime Minister Justin Trudeau on the right to impose a carbon tax on provinces. Two days of hearings in a Regina court began Wednesday. (Matt Smith/Canadian Press)

Dozens of lawyers will pack into a Regina courtroom this week to argue whether the federal government can impose a carbon tax on the provinces.

The province of Saskatchewan and the federal government are the two main entities that will make their case to the Saskatchewan Court of Appeal's five justices.

Watch the court proceedings in full here

The court will not be deciding the merits of a carbon tax. Instead, Saskatchewan is asking its highest provincial court to answer a question:

"The Greenhouse Gas Pollution Pricing Act was introduced into Parliament on March 28, 2018 as Part 5 of Bill C-74. If enacted, will this Act be unconstitutional in whole or in part?"

The province said it believes the carbon levy is an unfair, uneven, illegal tax and that it violates provincial jurisdiction.

The federal government argues it's a regulatory charge, not a tax, and that Ottawa has jurisdiction because carbon emissions are a matter of "national concern."

Ottawa is using a clause in the 1867 constitution that says that the federal government has responsibility for peace, order and good government.

"We have been expanding federal jurisdiction under the peace, order good government clause over and over again for half a century. For a century we barely used it but we've been using it more. And each time it happens, it feels kind of big," said constitutional lawyer and former deputy attorney general of Saskatchewan John Whyte.

"[Canada] will have to have the court believe that measures to reduce carbon emissions into the atmosphere is a matter of concern to the nation."

Whyte said they should be able to do that and that in his opinion the federal government's case is stronger than Saskatchewan's.

"There is no knock-down winning argument for the province here."

Both Canada and Saskatchewan will receive three hours to make their arguments, with Saskatchewan on Wednesday morning and the government of Canada on Thursday morning.

There are 16 interveners in the reference case: seven on Wednesday in favour of the province and nine on Thursday in favour of the federal governent. Three provinces — Ontario, New Brunswick and British Columbia — will each get 30 minutes to address the court. The 13 others interveners will receive 15 minutes each, which includes an address and questions from the judges.

The province of Saskatchewan's argument

Saskatchewan is asking the court to rule that the Greenhouse Gas Pollution Pricing Act is unconstitutional and should declared beyond federal authority or void and unenforceable.

The province argues that the federal government cannot impose a policy that treats provinces unequally.

"This case is not about the risks posed to the country by climate change. This case is not even about whether a carbon tax is a good or a bad way to reduce the greenhouse gas emissions that fuel climate change. This case is fundamentally about the nature of our federation," reads the province's written argument.

"The legislation is unconstitutional because it disregards fundamental principles of Canadian constitutional law, in particular, the principles of federalism."

Jason Kenney's Alberta Opposition UCP is intervening in this case, as is Ontario Premier Doug Ford's government. Both support Saskatchewan's position in the carbon tax fight. (Jeff McIntosh/Canadian Press, Chris Young/Canadian Press)

Don Morgan, Saskatchewan's Minister of Justice, said the federal government cannot tax provinces differently based on how much they like or dislike a specific province's plan to reduce carbon emissions.

"Our goal is not to have a carbon tax in our province and this is our ability to challenge," Morgan said.

"Politically it's important for the message to the people of our province that we are sticking up for them that this is something that's fundamentally important to us as an oil-producing, energy-exporting province."

Morgan said the province would not seek an injunction if its case is unsuccessful.

The government of Canada's argument

"Canada seeks the Court's opinion that the whole of the Greenhouse Gas Pollution Pricing Act is validly enacted under Parliament's power to pass laws for the peace, order, and good government of the nation as a whole respecting GHG emissions, being a matter of national concern," reads the government of Canada's argument.

The government's submissions asks the court, if it rules against the federal case, that it suspend its declaration until after the Supreme Court of Canada makes its ruling.

"Pollution is a national concern. Carbon pollution doesn't know any borders," Catherine McKenna, federal Environment Minister, said.

"Unfortunately some provinces did not step up, unfortunately provinces led by Conservative politicians, who believe it should be free to pollute."

Conservative leaders unite

Saskatchewan Premier Scott Moe and his ministers have repeatedly said they believe they have a strong case and will sway the court.

He has allies in Ontario Premier Doug Ford, New Brunswick Premier Blaine Higgs and Alberta opposition leader Jason Kenney, all of whom made their provinces interveners in Saskatchewan's case.

In 2017, a University of Manitoba legal scholar was commissioned by the Manitoba government to give a legal opinion on the constitutionality of the federal carbon tax plan. Bryan Schwartz determined Ottawa had the right to impose a carbon tax on Manitoba and other provinces — but the provinces have a good legal argument to make for their own carbon pricing plans.

"If we just say 'no,' we get Trudeau. If we go to court, we lose," Manitoba Premier Brian Pallister said in Oct. 2017.

One year later, Pallister announced the province would leave the federal framework. He said the province would pursue the courts but did not sign on as an intervener in the Saskatchewan case.

The court has given CBC permission to live stream proceedings. You can watch on our website beginning at 9:30 a.m. CST on Wednesday.

Schedule in order of appearance


  • Province of Saskatchewan - 3 hours.
  • Province of Ontario - 30 minutes.
  • Province of New Brunswick - 30 minutes.
  • SaskPower and SaskEnergy - 15 minutes.
  • The Canadian Taxpayers Federation - 15 minutes.
  • United Conservative Party (Alberta's provincial opposition party) - 15 minutes.
  • Agricultural Producers Association of Saskatchewan - 15 minutes.
  • International Emissions Trading Association - 15 minutes.


  • Government of Canada - 3 hours.
  • Province of British Columbia - 30 minutes.
  • The Canadian Public Health Association - 15 minutes.
  • Athabasca Chipewyan First Nation - 15 minutes.
  • Canadian Environmental Law Association And Environmental Defence Canada - 15 minutes.
  • Assembly of First Nations - 15 minutes.
  • David Suzuki Foundation - 15 minutes.
  • Ecofiscal Commission of Canada - 15 minutes.
  • Intergenerational Climate Coalition - 15 minutes.
  • Climate Justice et. al - 15 minutes.
  • Province of Saskatchewan (reply).

You can catch up on Wednesday's court proceedings here:  


Adam Hunter


Adam Hunter is the provincial affairs reporter at CBC Saskatchewan, based in Regina. He has been with CBC for 13 years. He hosts the CBC podcast On the Ledge. Follow him on Twitter @AHiddyCBC. Contact him:

with files from CBC's Bonnie Allen


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