Leading environmental groups have filed a lawsuit against the Ontario government over the cancellation of the province's cap-and-trade program.

Lawyers for Ecojustice, in conjunction with the uOttawa-Ecojustice Environmental Law Clinic, filed the suit on behalf of Greenpeace Canada, according to a news release issued Tuesday afternoon.

The suit aims to halt the regulation, approved in July, which calls for the end of the province's cap-and-trade program. The program was brought in by the previous Liberal government.

We're suing to remind the Premier that winning an election does not give his government carte blanche to ignore the statutory rights of Ontarians. - Charles Hatt, Ecojustice's lawyer

The lawsuit alleges that Doug Ford's Progressive Conservative government "unlawfully failed" to engage in public consultations over the cancelling of the program, as required by Ontario's Environmental Bill of Rights.

"The Ford government's first action when it stepped into office was to gut a program designed to reduce greenhouse gas pollution, without offering any immediate alternative," Charles Hatt, Ecojustice's lawyer, said in a statement.

"We're suing to remind the Premier that winning an election does not give his government carte blanche to ignore the statutory rights of Ontarians to be consulted on major changes to the laws and regulations that protect them from climate change."

The lawsuit, filed Tuesday in Ontario Superior Court, asks the court to quash the regulation.

The applicants have been granted an expedited hearing, which is tentatively scheduled for Sept. 21.

Andrew Brander, a spokesperson for Environment Minister Rod Phillips, maintained the province "extensively" consulted with the people of Ontario about rescinding the cap-and-trade program, calling it "expensive and ineffective."

"We are confident that [the legislation] will meet all necessary requirements as we continue to undertake a full range of consultative steps," he said in an email to CBC Toronto.

Ontario's attorney general did not immediately respond to CBC Toronto's requests for comment.

Province said move would save families money

Scrapping cap-and-trade was one of Ford's key promises during the spring election campaign.

In July, the newly elected PC government unveiled legislation to end cap-and-trade, claiming it would save the average Ontario family $260 per year in energy and fuel charges, as well as other "indirect costs."

In a news release at the time, Environment Minister Rod Phillips said the new proposed legislation, if passed, would compensate eligible companies that bought credits as part of the program, and would also include new measures to replace cap-and-trade with "a better plan for achieving real environmental goals."

"Ontario's carbon tax era is over," Phillips said in the news release.

The legislation also called for the province to set targets for reducing greenhouse gas emissions and to publish a plan to fight climate change.

Critics at the time suggested the government could be on the hook for billions of dollars to compensate companies that have already purchased credits. It was also unclear how the lost revenue would be replaced, if at all.

The government has already axed programs that are funded by proceeds of cap-and-trade, including GreenOn, which offered rebates to homeowners who made specific environmentally friendly choices during home renovations. The government also scrapped a program that offered incentives to drivers who bought electric vehicles.

When it cancelled that program, the province promised to honour the incentive for those who have their vehicle delivered, registered and plated if it was purchased from a dealer before Sept. 10.

Tesla owners were left out of that deal, because they purchase their vehicles directly from the manufacturer. However, they recently won a court decision allowing them to be part of the scaling down of the program.