In 1975, the governments of Quebec and Canada and Cree and Inuit communities in northern Quebec entered into the James Bay Treaty. A proponent sought to develop a vanadium mine in the territory covered by the Treaty. The mining project fell within provincial jurisdiction over natural resources. However, the mine would also impact fisheries and fish habitats, an area of federal jurisdiction, and therefore required a permit from the federal Minister of Fisheries. Pursuant to federal legislation, before issuing a permit in such circumstances, the Minister of Fisheries is required to comply with the Canadian Environmental Assessment Act (“CEAA”) and conduct an environmental assessment.

The government of Quebec argued that the CEAA did not apply in the territory covered by the Treaty because the Treaty provided for a single, separate environmental review process. The government of Canada and the Cree First Nation argued that, notwithstanding the Treaty, the Minister of Fisheries was required to conduct an environmental assessment.

A 5-4 majority of the Court agreed with the government of Canada and the Cree First Nation. The majority held that the Treaty was drafted by skilled individuals, with legal advice, and that “the Court ought to do the parties the courtesy of respecting the rights and obligations in the terms they agreed to.” Under the Treaty, all federal laws of general application respecting environmental protections apply insofar as they are not inconsistent with the Treaty. The majority held that there were no inconsistencies between the Treaty and the CEAA. The CEAA procedure governs, but must be applied in a way that respects the Crown’s duty to consult the Cree on matters affecting their rights under the Treaty.