Exclusiveness of authority in Canadian constitutional law is a legal doctrine that impedes the application of the law beyond the constitutional competence of the person who issued it. For example, when a provincial law applies to an object that is within the competence of the federal government, its provisions regarding the subject will be excluded from interpretation. The doctrine of exclusivity is applied when the legislation touches on an important or essential element of an object that is outside the control competence.
Although some discussions are still ongoing, it is generally recognized that the doctrine applies to both provincial and federal levels of government. However, almost all case law affects situations where provincial laws apply to subjects of federal competence.