The Supreme Court will issue a decision Thursday morning on the fate of the federal price on pollution.
It could become a landmark case for the division of federal and provincial powers, and is a pivotal decision in the world of Canadian climate politics.
The court will decide whether the Greenhouse Gas Pollution Pricing Act is constitutional.
The act, passed in 2018, imposes a minimum price on greenhouse gas emissions in provinces that don’t have an equivalent system of their own.
Alberta, Saskatchewan and Ontario all challenged the law in court, saying it infringes on their taxing powers and their constitutionally-protected right to develop their own natural resources.
The carbon price is a critical piece of the Liberal climate plan, but has been fodder for partisan fighting with conservative politicians, provincially and federally, for years.
The federal carbon price on individuals and smaller businesses currently applies in Alberta, Saskatchewan, Manitoba and Ontario. The price is applied on the cost of buying fuels, from gasoline and diesel to aviation fuel, coal and natural gas.
At $30 a tonne right now, it adds about 8.8 cents per litre to gasoline, and about $15 a month to an average household natural gas bill.
Ottawa returns the revenues from the carbon price mainly through tax rebates to families in the provinces where the national price is paid.
A separate system for big emitters charges the price on a portion of their actual emissions. It only applies fully in Manitoba and Prince Edward Island.
The court cases challenged the existence of both programs.
This report by The Canadian Press was first published March 25, 2021.