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Although federal and provincial governments have exclusive heads of power under Canada’s Constitution Act, 1867, in practice, there can be overlap in the types of activities that both governments can regulate. But not all overlap is permitted. A key constitutional doctrine—interjurisdictional immunity—prevents the laws of one government from impairing the core of the other’s legislative powers. In 2007, the Supreme Court of Canada signaled that this doctrine should be applied with restraint. But more recent cases have confirmed that it remains an important and robust tool. In Opsis Airport Services Inc. v. Québec (Attorney General)1, the Supreme Court affirmed this trend, stressing the continued importance of interjurisdictional immunity. The Court also indicated it may be applied more flexibly in the future.
Opsis involved two appeals from the Québec courts. The first dealt with Opsis Airport Services Inc.2, which operates and manages various security services at Trudeau International Airport in Montréal. The second dealt with Québec Maritime Services Inc. (QMS)3, which performs loading operations for transatlantic ships at a port in La Malbaie, Québec.
Both companies were charged with violations of the Private Security Act (PSA), a Québec statute that mandates a licensing regime for private security services. There was no dispute that Opsis and QMS violated the PSA. But they argued that, under the doctrine of interjurisdictional immunity, the PSA was inapplicable to their businesses.
In a unanimous judgment, the Supreme Court held that the PSA was inapplicable to the parties. Despite earlier caution that interjurisdictional immunity should be “applied with restraint”, the Court recognized that the doctrine remains an essential and important part of Canadian federalism. Applying the doctrine on the facts, it held that the PSA impaired the core of Parliament’s power over aeronautics (in Opsis’s appeal) and navigation and shipping (in QMS’s appeal) and was thus inapplicable to both companies. They were therefore acquitted of all charges.
The Court explained the two-part test for interjurisdictional immunity in a way that both confirms the continuing importance of the doctrine and expands its potential application:
Although interjurisdictional immunity was the only constitutional doctrine at issue, the Court also clarified its relationship with paramountcy (the constitutional doctrine that addresses conflicts between federal and provincial law). The Court had previously held that interjurisdictional immunity should be addressed only after considering whether paramountcy applies. In Opsis, the Court reversed itself and indicated that it will be “logical and appropriate” to consider interjurisdictional immunity first.
Applying the doctrine, the Court held that the appellants had met the two-part test:
Even though only some provisions of the PSA impaired the core of the federal powers, the Court held that the most appropriate remedy was to “read down” the entire PSA so as not to apply to the appellants’ activities. That is because the impairing provisions could not be severed from the rest of the Act—the enforcement regime related to the Bureau’s essential function. Thus, severing only the impugned provisions might change the nature of the PSA as intended by the Québec legislature.
Despite past cautions about interjurisdictional immunity, Opsis confirms that the doctrine is alive and well—it “continues to play an essential role”. Indeed, given the Court’s clarifications about the role of precedent and the focus of impairment on potential effects, Opsis may well lead to an even broader application of the doctrine in the future.
One interesting question that arises out of Opsis is whether the Court will recognize “reverse” interjurisdictional immunity, to prevent the intrusion of federal law in areas of provincial jurisdiction on the appropriate facts. To date, all the Supreme Court’s cases on interjurisdictional immunity relate to whether provincial law applies to federally regulated entities and undertakings. But the language used by the Court in Opsis strongly implies that it might in the future be used to render federal law inapplicable to provincially regulated entities and undertakings. This has been affirmed in principle by previous cases, but never applied. However, it was discussed by the Court of Appeal for Alberta in the reference relating to the Impact Assessment Act and may turn out to be an important issue in the future, particularly in relation to section 92A, which gives provinces exclusive jurisdiction over non-renewable resources and the generation of electricity.
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