What principle states that a court will intercede when a law is both valid and inconsistent?

The principle that states a court will intercede when a law is both valid and inconsistent is known as the Paramountcy Principle. This principle arises primarily in the context of federalism in Canada, where both federal and provincial legislatures can enact valid laws. When a conflict exists between a federal law and a valid provincial law, the federal law takes precedence under the doctrine of paramountcy.

The rationale behind the Paramountcy Principle is rooted in the need for a cohesive legal framework in a federal system. It ensures that laws meant to operate at different levels do not conflict and cause legal uncertainty. When a provincial law contradicts a valid federal law, the court will determine that the federal law prevails, thereby upholding the supremacy of Parliament as established in the Constitution. This establishes clarity and resolves disputes that may arise from overlapping jurisdictions.

Although the other options pertain to significant aspects of Canadian constitutional law, they do not specifically address the scenario of a valid but inconsistent law. For instance, the Double Aspect Doctrine relates to situations where both federal and provincial laws can coexist on the same subject matter without conflict, while the Override Clause allows legislatures to pass laws that may violate certain rights under the Canadian Charter of Rights and Freedoms, and Exclusive Jurisdiction pertains to areas