Paramountcy (Canada)

In Canadian constitutional law, the doctrine of paramountcy establishes that where there is a conflict between valid provincial and federal laws, the federal law will prevail and the provincial law will be inoperative to the extent that it conflicts with the federal law. Unlike interjurisdictional immunity, which is concerned with the scope of the federal power, paramountcy deals with the way in which that power is exercised.

Paramountcy is relevant where there is conflicting federal and provincial legislation. As Major J explained in Rothmans:

11. The doctrine of federal legislative paramountcy dictates that where there is an inconsistency between validly enacted but overlapping provincial and federal legislation, the provincial legislation is inoperative to the extent of the inconsistency....

Claims in paramountcy may arise from two different forms of conflict:

The doctrine was first expressed in the Local Prohibition Case, and was subsequently described by Lord Dunedin in Grand Trunk v. Attorney General of Canada thus:

First, ... there can be a domain in which provincial and Dominion legislation may overlap, in which case neither legislation will be ultra vires, if the field is clear; and, secondly, ... if the field is not clear, and in such a domain the two legislations meet, then the Dominion must prevail.

Historically, the doctrine was interpreted very strictly. When there was any overlap between federal or provincial laws the federal law would always render the provincial law inoperative even where there was no conflict. It was over time that courts and academics began to interpret the power as only applying where conformity to one law would necessarily violate the other. The Supreme Court of Canada adopted the latter interpretation in the decision of Smith v. The Queen. The Court held that there must be an "operational incompatibility" between the laws in order to invoke paramountcy.

The modern use of the paramountcy doctrine was articulated in Multiple Access v. McCutcheon. In that case, both the provincial and federal governments had enacted virtually identical insider trading legislation. The Court found that statutory duplication does not invoke paramountcy as the court had the discretion to prevent double penalties. Instead, paramountcy can only be invoked when then compliance with one means the breach of the other.

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