The Supremacy Clause refers to the foundational principle that, in general, federal law takes precedence over any conflicting state law. Established under Article VI, Paragraph 2 of the U.S. Constitution, the Supremacy Clause enables the federal government to enforce treaties, create a central bank, and enact legislation without interference from the states. It does not, however, allow the federal government to review or veto state laws before they take effect.
The Supremacy Clause underpins the broader doctrine of preemption, where if laws are in conflict, the law of a higher authority can preempt the law of a lower authority if the superiority of the former is stated expressly or implied. Traditionally, when it is not indicated, federal law does not preempt state law in areas traditionally regulated by states, unless Congress’s intent to preempt is clear. In areas where the federal government has historically significant regulatory involvement, preemption is less likely to apply. Today, disputes usually involve statutory interpretation rather than its scope of application.
See also: Constitutional Clauses
[Last updated in June of 2024 by the Wex Definitions Team]