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The question of preemption arises because the Constitution establishes a federal system with two governments (one federal and one state) that have overlapping power to regulate the same matters involving the same parties in the same territory. To succeed, such a system requires a means of deciding when federal law displaces state law. The Founders chose the Supremacy Clause (reinforced by Article III) to perform this function. Although seemingly one-sided, the Clause actually incorporates several important political and procedural safeguards designed to preserve the proper balance between the governance prerogatives of the federal government and the states. It does this by recognizing only three sources of law as "the supreme Law of the Land" – the "Constitution," "Laws," and "Treaties" of the United States. Elsewhere, the Constitution prescribes precise and cumbersome procedures to govern the adoption of each source of supreme federal law. These procedures establish the exclusive means of adopting "the supreme Law of the Land." By requiring the participation and assent of multiple actors subject to the political safeguards of federalism, these procedures make supreme federal law relatively difficult to adopt. More importantly, these procedures suggest exclusivity because the Constitution guarantees states (regardless of size or population) equal suffrage in the Senate and gives the Senate (or the states) an absolute veto over the adoption of each and every source of law recognized by the Supremacy Clause. This means that courts must identify an applicable provision of the "Constitution," "Laws," and "Treaties" of the United States adopted pursuant to specified procedures before they may preempt state law. By operation of the Supremacy Clause, these three sources override contrary state law. The negative implication of the Clause, however, is that state law continues to govern in the absence of "the supreme Law of the Land." This process-based understanding of preemption has potential implications for two related federalism doctrines: the presumption against preemption and the more controversial clear statement requirement. The traditional presumption against preemption maintains "that the historic police powers of the States [are] not to be superseded by [a] Federal Act unless that was the clear and manifest purpose of Congress." A clear statement rule is similar in function but requires that Congress make its intent to preempt state law clear on the face of the statute. In addition, some formulations go farther by suggesting that "if Congress intends to alter the usual constitutional balance between the States and the Federal Government, it must make its intention to do so unmistakably clear in the language of the statute." Critics of these doctrines argue that the presumption against preemption contradicts the Supremacy Clause, and that clear statement rules "amount to a ‘backdoor’ version of the constitutional activism." Although certainly subject to abuse, this paper suggests that both doctrines – if properly limited – may play a useful role in implementing the Constitution’s political and procedural safeguards of federalism.

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GWU Law School Public Law Research Paper No. 515; GWU Legal Studies Research Paper No. 515

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