Supreme Court of Canada clarifies when provincial laws apply to activities or businesses under federal jurisdiction

On May 30, 2025, the Supreme Court of Canada rendered its long-awaited decision in the Opsis and Maritime Services cases. In a unanimous judgment, it ruled that the Quebec Private Security Act (“PSA”) was inapplicable to the appellants by virtue of the doctrine of interjurisdictional immunity. The decision, signed by “The Court”, demonstrates that, despite the Court’s past criticisms of the doctrine, it undeniably believes in its relevance to Canadian federalism.

Importantly, the decision sheds light on the methodology that must be followed to determine if a provincial statute applies to activities or businesses under federal jurisdiction, such as banking, telecommunication, aeronautics and interprovincial or international transportation.

Key Takeaways

• The application of the doctrine of interjurisdictional immunity is not limited to the core of heads of power already recognized in judicial precedents;
• The security of airport and marine facilities falls under the core of federal jurisdiction and, as such, is immune from provincial impairment;
• The mere existence of a licensing scheme is insufficient to trigger the application of the doctrine of interjurisdictional immunity, but it may be so if obtaining the licence is subject to unreasonable requirements or to the exercise of a broad discretion;
• In order to determine whether a law impairs the core of the exclusive power of the other level of government, courts may consider the effects of the application of the law even when the parties have not adduced evidence in this regard, and whether these effects have materialized or not. They may also consider the effects of the law on the “vital or essential part of an undertaking”;
• If a declaration of inapplicability targeting only the impairing provisions would change the nature of the legislative scheme intended by the legislature, the appropriate remedy is to read down the statute as a whole.

Context

The three appellants in this appeal — a business that provided airport security services, another that performed loading operations on transatlantic ships out of a terminal in La Malbaie, and an employee who monitored and controlled access to the port facility — were charged with having contravened the provisions of the PSA, which required them to hold a licence to carry on a private security activity. They contested their statements of offence on the basis that the PSA is inapplicable to them by virtue of the doctrine of interjurisdictional immunity.

Analysis

As a preliminary consideration, the Court states that, before determining whether the doctrine of interjurisdictional immunity is triggered, “it must be ensured that the particular facts of the case in question fall within the impugned statute”. In this case, the Court concludes that the PSA is applicable to private security activities that are carried out in “public” places, like port or airport facilities.

Then, the Court examines the doctrine of interjurisdictional immunity. When the doctrine applies, the impugned provisions remain valid but are declared inapplicable to matters that would fall under the core of the exclusive head of power of the other order of government. A provincial law is inapplicable when (i) it intrudes on the core of a federal head of power and (ii) that intrusion amounts to an impairment.

In this appeal, the Court finds that the licensing scheme set out in the PSA intrudes on the core of federal heads of power. It rules that the security of airports unquestionably falls within the core of federal jurisdiction over aeronautics, while the security of marine facilities and their operations fall within the core of federal jurisdiction over navigation and shipping, even if there is no specific judicial precedent to that effect.

Secondly, the Court concludes that the intrusion caused by the PSA amounts to an impairment. The Court affirms that it cannot only examine the provisions pertaining to obtaining licences, which were the ones in issue. Licensing schemes generally have to be examined as a whole and other aspects of the scheme may have to be considered.

While the mere existence of a licensing scheme is insufficient to trigger the application of the doctrine of interjurisdictional immunity, it may amount to an impairment if the licence is subject to unreasonable requirements or to the exercise of a broad discretion that has the effect of giving the other level of government the final say on the possibility of carrying on activities falling with the core of an exclusive power.

In this case, the Court rules that some aspects of the licensing scheme amount to an impairment:

• The Bureau’s power to “suspend, cancel or refuse to renew the agent licence of a licence holder” where, among other things, the holder “has violated the standards of conduct determined by regulation”. The Court notes that the Bureau has the power to subject agent licence holders to standards of conduct whose content is determined by it alone, and that it is up to the Bureau to assess whether or not the standards are met, regardless of how general they are;
• The Bureau’s power to issue directives to an agency licence holder, which gives the Bureau a broad discretion to dictate how the agency licence holder must carry on its private security activities;

Because the impairing provisions cannot be severed from the coherent whole formed by the statute, the Court declares that the PSA as a whole is inapplicable to the appellants.

Conclusion

In light of the principles set out in this important judgment, federal undertakings may want to reassess whether they have to comply with some provincial regulatory schemes, especially regimes that include a licence, permit or authorization requirement, schemes that grant a discretionary power to a provincial body, or schemes that involve security considerations.

Disclaimer: The authors represented an intervener in this appeal before the Supreme Court of Canada. The opinions expressed in this blog post are solely theirs.

If you have questions about this decision, reach out to our Litigation and Dispute Resolution Group.