The Supreme Court of Canada has found the federal government’s Impact Assessment Act (IAA) to be largely unconstitutional.

The 5-2 decision was part of a reference case initiated by the Alberta government.

Enacted in 2019 by the Trudeau government and originally referred to as Bill C-69, the IAA gave power to federal regulators regarding the potential environmental and social impacts of different resource and infrastructure projects – notably pipeline development.

Since being implemented, the IAA has received stark criticism from conservative politicians, particularly in Alberta, where it was dubbed the “no more pipelines act.”

Alberta filed a constitutional challenge with the Alberta Court of Appeal and won in a 4-1 decision in which the court referred to the law as an “existential threat” to the Canadian Constitution.  

Ottawa appealed that opinion and the Supreme Court held hearings in March.

Chief Justice Richard Wagner said that Sections 81 to 91 of the IAA were not in violation of the constitution because those sections involved projects that are carried out on federal land and are financed by the federal government. 

Therefore, they fall under federal jurisdiction and may be separated out as constitutional and unchallenged. 

Outside of those sections however, the bulk of the scheme involves regulations on “designated projects,” which are in fact, unconstitutional, according to Wagner.  

Designated projects, according to the IAA, are projects that are subject to ministerial order and regulation. 

“In my view, Parliament has plainly overstepped its constitutional competence in enacting this designated projects scheme,” wrote Wagner.

The court found that the law was so broad that it interfered with provincial jurisdiction.

Justices Andromache Karakatsanis and Mahmud Jamal dissented, finding the law to be constitutional in its entirety.

There was much anticipation in the lead up to Friday’s decision from legal experts, who said this decision will help bring some clarity to what has been a highly contentious area of law. 

“The words of the court, the opinion of the court, really will define the landscape for federal impact assessment and environmental assessment for decades to come,” said David Wright, associate professor at the Faculty of Law for the University of Calgary, in an interview with CBC News

Alberta Premier Danielle Smith celebrated the decision by posting to X, “Alberta Wins! Canada Wins!”