Attorney General of British Columbia v. Attorney General of Canada

(British Columbia) (Civil) (As of Right)


Constitutional law - Division of powers - Constitutional law - Division of powers - Interprovincial undertakings - Environmental protection - Trans Mountain Pipeline - Whether it is within the legislative authority of the Legislature of British Columbia to enact certain amendments to the Environmental Management Act, R.S.B.C. 2003, c. 53 - If the answer is yes, whether the legislation is applicable to hazardous substances brought into the province by means of interprovincial undertakings - If the answer to both questions is yes, whether existing federal legislation would render all or part of the amendments inoperative.


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In April 2018, the Province of British Columbia asked the Court of Appeal to provide an opinion as to whether the Province had jurisdiction to regulate certain environmental aspects of the Trans Mountain Pipeline. The Province acknowledged that the pipeline is an interprovincial (and therefore federal) undertaking, but asserted that provincial environmental legislation has long affected aspects of federal undertakings without serious challenge, that the heads of power set out in ss. 91 and 92 of the Constitution Act, 1867, are not “watertight compartments”, and that the jurisprudence has recognized on occasion that certain functions are best carried out by the level of government closest to the people affected. In the Province’s view, the proposed provincial legislative amendments related either to property and civil rights in the Province or were matters of a merely local or private nature under s. 92 of the Constitution Act, 1867, and were therefore within the Province’s legislative authority. Canada asked the Court of Appeal to find the proposed amendments ultra vires or inoperative, with the view to eliminating the uncertainty surrounding the pipeline project. The Court of Appeal found the amendments to lie beyond provincial jurisdiction.