Common Interpretation

The Supremacy Clause


When the Philadelphia Convention got under way in May 1787, Governor Edmund Randolph of Virginia presented what has come to be known as “the Virginia plan”—a collection of resolutions forming a blueprint for the Constitution. As amended a few days later, one of the resolutions included the following proposal: “the National Legislature ought to be impowered . . . to negative all laws passed by the several States, contravening in the opinion of the National Legislature the articles of Union, or any treaties subsisting under the authority of the Union.”

At first, supporters of this idea seemed optimistic about its chances. In early June, indeed, Charles Pinckney and James Madison moved to extend the proposed congressional “negative” so as to reach all state laws that Congress deemed “improper.” This motion, however, went down to defeat. The next month, over Madison’s objections, the Convention rejected the narrower version of the power too. In place of the proposed congressional “negative,” the Convention approved a precursor of the Supremacy Clause. That Clause went through various changes in the ensuing months, but the final version says:

This Constitution, and the Laws of the United States which shall be made in Pursuance thereof; and all Treaties made, or which shall be made, under the Authority of the United States, shall be the supreme Law of the Land; and the Judges in every State shall be bound thereby, any Thing in the Constitution or Laws of any State to the Contrary notwithstanding.

Instead of giving Congress additional powers, the Supremacy Clause simply addresses the legal status of the laws that other parts of the Constitution empower Congress to make, as well as the legal status of treaties and the Constitution itself. The core message of the Supremacy Clause is simple: the Constitution and federal laws (of the types listed in the first part of the Clause) take priority over any conflicting rules of state law. This principle is so familiar that we often take it for granted. Still, the Supremacy Clause has several notable features.

To begin with, the Supremacy Clause contains the Constitution’s most explicit references to what lawyers call “judicial review”—the idea that even duly enacted statutes do not supply rules of decision for courts to the extent that the statutes are unconstitutional. Some scholars say that the Supremacy Clause’s reference to “the Laws of the United States which shall be made in Pursuance [of the Constitution]” itself incorporates this idea; in their view, a federal statute is not “made in Pursuance [of the Constitution]” unless the Constitution really authorizes Congress to make it. Other scholars say that this phrase simply refers to the lawmaking process described in Article I, and does not necessarily distinguish duly enacted federal statutes that conform to the Constitution from duly enacted federal statutes that do not. But no matter how one parses this specific phrase, the Supremacy Clause unquestionably describes the Constitution as “Law” of the sort that courts apply. That point is a pillar of the argument for judicial review. In addition, the Supremacy Clause explicitly specifies that the Constitution binds the judges in every state notwithstanding any state laws to the contrary.

The Supremacy Clause also establishes a noteworthy principle about treaties. Under the traditional British rule, treaties made by the Crown committed Great Britain on the international stage, but they did not have domestic legal effect; if Parliament wanted British courts to apply rules of decision drawn from a treaty, Parliament needed to enact implementing legislation. The Supremacy Clause breaks from this principle. Subject to limits found elsewhere in the Constitution, treaties are capable of directly establishing rules of decision for American courts.

This aspect of the Supremacy Clause reflected concerns that individual states were jeopardizing the fledgling nation’s security by putting the United States in violation of its treaty obligations. For instance, at the end of the Revolutionary War, Article IV of the Treaty of Peace between the United States and Great Britain had specified that “creditors on either side[] shall meet with no lawful impediment to the recovery of the full value in sterling money, of all bona fide debts heretofore contracted.” Nonetheless, several states enacted or retained debtor-relief laws whose enforcement against British creditors would violate this promise, and British diplomats argued that these violations excused Britain’s own failure to withdraw all armies and garrisons from the United States. The Supremacy Clause responded to this problem: just as state courts were not supposed to apply state laws that conflicted with the Constitution itself, so too state courts were not supposed to apply state laws that conflicted with Article IV of the Treaty of Peace. Indeed, the peculiar wording of the Supremacy Clause—covering treaties already “made . . . under the Authority of the United States” as well as treaties that “shall be made” in the future—was specifically designed to encompass pre-existing agreements like the Treaty of Peace. While modern scholars have debated the circumstances in which treaties should be understood to establish rules of decision for cases in American courts, the Supremacy Clause unquestionably makes such treaties possible.

Under the Supremacy Clause, the “supreme Law of the Land” also includes federal statutes enacted by Congress. Within the limits of the powers that Congress gets from other parts of the Constitution, Congress can establish rules of decision that American courts are bound to apply, even if state law purports to supply contrary rules. Congress also has at least some authority to put certain topics wholly off limits to state law, or otherwise to restrict what state law can validly say about those topics. As long as the directives that Congress enacts are indeed authorized by the Constitution, they take priority over both the ordinary laws and the constitution of each individual state. (During the ratification period, Anti-Federalists objected to the fact that federal statutes and treaties could override aspects of each state’s constitution and bill of rights. But while this feature of the Supremacy Clause was controversial, it is unambiguous.)

In modern times, the Supreme Court has recognized various ways in which federal statutes can displace or “preempt” state law. Some federal statutes include express “preemption clauses” forbidding states to enact or enforce certain kinds of laws. A few other federal statutes have been interpreted as implicitly stripping states of lawmaking power throughout a particular field. But even when a federal statute does not contain an express preemption clause, and even when the statute does not implicitly occupy an entire field to the exclusion of state law, the directives that the statute validly establishes still supersede any conflicting directives that the law of an individual state might purport to supply.

Every year, courts decide an enormous number of cases that involve whether a particular federal statute should be understood to preempt a particular aspect of state law. Often, the key disputes in these cases boil down to questions of statutory interpretation. (If the relevant federal statute includes a preemption clause, what does the clause mean? Should any additional instructions about preemption be inferred? And what is the precise content of all the other legal directives that the statute establishes, whether expressly or by implication?) But apart from disputes about what the relevant federal statute should be understood to say and imply, and apart from any disputes about whether the Constitution really gives Congress the power to say and imply those things, some preemption cases may implicate disagreements about the Supremacy Clause itself. Of course, the basic principle that valid federal statutes preempt conflicting rules of state law is not controversial. But different judicial opinions suggest different views about what counts as a conflict for this purpose, and some of those disagreements may grow out of the Supremacy Clause: while there is no doubt that the Supremacy Clause sometimes requires courts to disregard rules of decision purportedly supplied by state law, there is room for debate about the precise trigger for that requirement.

Matters of Debate

Preemption, Purposivism, and the Supremacy Clause


Just as television coverage of breaking news can “preempt” the programs that would otherwise be airing, so too valid federal statutes can preempt state law that would otherwise apply. That is a consequence of the Supremacy Clause, which makes valid federal statutes part of “the supreme Law of the Land” and says that “the Judges in every State shall be bound thereby, any Thing in the Constitution or Laws of any State to the Contrary notwithstanding.” But exactly what does it mean to say that federal statutes are “supreme” over state law? Under what circumstances does the Supremacy Clause require judges to disregard otherwise applicable state law because it is contrary to federal law?

The Supremacy Clause definitely does not mean that each state must base all of its own laws on the same policy judgments reflected in federal statutes. For instance, the fact that Congress has chosen to establish federal income taxes, but has mostly refrained from establishing federal sales taxes, does not mean that state legislatures have to make the same choice as a matter of state law. Of course, states cannot exempt people from having to pay federal income taxes as required by federal law. But states do not have to structure their own state tax systems on the same model; if state lawmakers think that sales taxes are better than income taxes, states can fund their state governments that way. Similarly, the fact that Congress has made the possession of certain drugs a federal crime does not prevent states from following a different policy as a matter of state law. While states are not in charge of whether drug possession is a federal crime, they are in charge of whether it is also a state crime.

In these examples, though, the relevant state law does not interfere with the operation of the federal statute. Federal authorities can enforce the federal income tax or federal drug laws without regard to whether state law imposes a state income tax or criminalizes possession of the same drugs.

When application of state law would interfere with the operation of a valid federal statute, modern courts are more likely to conclude that the state law is preempted. Ever since Hines v. Davidowitz (1941), the Supreme Court has sometimes articulated a broad version of this idea.  The majority opinion in Hines arguably suggested that state law is preempted whenever its application “stands as an obstacle to the accomplishment and execution of the full purposes and objectives” behind a valid federal statute, and later cases have repeated this formulation.

I do not think that the Supremacy Clause itself compels this understanding of the preemptive effect of federal statutes. In my view, the fact that valid federal statutes are “the supreme Law of the Land” and “the Judges in every State shall be bound thereby” means that the judges in every state must follow all legal directives validly supplied by those statutes. In any case where following some aspect of state law would require disregarding a legal directive validly supplied by a federal statute, judges should conclude that the state law is preempted; if judges have to choose between applying state law and applying a legal directive validly supplied by a federal statute, the Supremacy Clause gives priority to the federal law. But unless state law contradicts federal law in this sense (so that judges must choose which one to follow), nothing in the Supremacy Clause prevents judges from following both.

When the Supremacy Clause was adopted, judges had long been using an analogous test to decide whether one law repeals another. Ordinarily, statutes enacted by the same legislative body are cumulative: if a legislature enacts two statutes at different times, and if Statute #2 does not say that it repeals Statute #1, courts normally will apply both. But that is not possible if the two statutes supply contradictory instructions for the same issue. With respect to statutes enacted by a single legislature, courts traditionally have handled such contradictions by giving priority to the more recent statute. With respect to conflicts between state and federal law, the Supremacy Clause establishes a different hierarchy: federal law wins regardless of the order of enactment. But this hierarchy matters only if the two laws do indeed contradict each other, such that applying one would require disregarding the other. In my view, then, the trigger for preemption under the Supremacy Clause is identical to the traditional trigger for repeals. In support of this conclusion, there is evidence that the Supremacy Clause was drafted and discussed in light of existing legal doctrines about repeals.

Even if I am right about the Supremacy Clause’s test for preemption, though, applying that test in particular cases requires courts to interpret the relevant federal statutes to identify all the legal directives that those statutes establish. That is a more contentious project than nonlawyers might assume. Federal statutes often are understood to imply some things that they do not say on their face, and legal directives that are established by implication can be just as valid as other legal directives. Different judges, however, have different views about the circumstances in which courts can properly read things into federal statutes (and, perhaps, about the extent to which courts can properly articulate subsidiary rules designed to help implement those statutes). The competing schools of thought include one approach called “textualism” and another called “purposivism.”

Another Perspective

This essay is part of a discussion about The Supremacy Clause with Kermit Roosevelt, Professor of Law, University of Pennsylvania Law School. Read the full discussion here.

The Supreme Court issued its opinion in Hines during the heyday of purposivism, and there is reason to think that Hines’s emphasis on Congress’s “purposes and objectives” was more about statutory interpretation than about the basic test for preemption established by the Supremacy Clause. In keeping with that idea, the modern Supreme Court tends to portray the Hines formulation as a guide to the “pre-emptive intent” that courts should attribute to particular federal statutes. On this way of thinking, the Hines formulation reflects a presumption about Congress’s likely desires. The idea is that when Congress enacts a federal statute, Congress presumably wants to preempt state laws that would “stand[] as an obstacle to the accomplishment and execution of the full purposes and objectives of Congress,” and courts should give effect to this presumed intention.

If, as a matter of statutory interpretation, a particular federal statute implicitly forbids states to enact or enforce laws that would interfere with specified federal purposes, and if Congress has the constitutional power to impose this restriction on state law, then the Supremacy Clause would require courts to pay attention. After all, if a federal statute validly strips states of the power to enact or enforce certain kinds of laws, a court that gave effect to such a state law would be disregarding a valid federal directive, in violation of the Supremacy Clause. Considered as a principle of statutory interpretation, then, the Hines formulation can co-exist with my understanding of the Supremacy Clause.

Still, the Hines formulation may not be a very good principle of statutory interpretation. To begin with, many textualists doubt that courts are in a good position to identify the full purposes and objectives behind any particular federal statute. In any event, members of Congress would not necessarily want to run roughshod over all state laws that serve competing goals. To take a simple example, a federal statute that exempts multinational companies from certain federal taxes might have the purpose of luring business to the United States, but courts should not automatically infer that Congress is forbidding states to enforce their own generally applicable tax laws against such companies. Likewise, a federal statute that gets rid of prior federal regulations in a particular area might be designed to reap the benefits of the free market, but courts should not automatically infer that Congress must have wanted to prevent individual states from enacting any regulations of their own in the same area.

In the past few decades, the Supreme Court has become somewhat more sensitive to these points. As early as 1992, Justice Kennedy wrote that “[o]ur decisions establish that a high threshold must be met if a state law is to be pre-empted for conflicting with the purposes of a federal Act.” More recently, Chief Justice Roberts has quoted this statement approvingly, and Justices Alito and Sotomayor have both quoted Chief Justice Roberts’s quotation. Meanwhile, Justice Thomas has rejected the Hines formulation entirely.

At the very least, the Supremacy Clause does not itself require judges to conduct the analysis described in Hines and its progeny. In my view, that analysis is appropriate only to the extent that individual federal statutes are properly interpreted to call for it.

 Some of the arguments presented here initially appeared in Preemption, 86 Virginia Law Review 225 (2000).

Matters of Debate

The Nation and the States


Which comes first, the nation or the states? Who is the ultimate sovereign in our American system—a national people represented by the federal government, or the several states considered as distinct political entities?

This is perhaps the most basic question about the U.S. Constitution and the system it created. The relationship between the states and the federal government is one of the most fundamental fault lines of constitutional theory. In many of its aspects, the relationship is deeply contested, and no settled answer exists. There are two very different ways of understanding America. The nationalist vision imagines a single national people—We the People—coming together to create a government that represents all of them and is superior to—in a real sense, more American than—the individual states. The federalist vision imagines states delegating some of their powers to a federal government created to act as their agent in certain matters.

Some of the questions thrown up by the tension between these two visions have been resolved. It is settled now that the U.S. Supreme Court has the power to reverse the decisions of state supreme courts in appropriate cases, and that state courts must accept U.S. Supreme Court interpretations of the Constitution and federal law. It is settled that states cannot nullify federal laws—though constitutional amendments giving them such power have been proposed.

In other areas of law, though, the struggle persists. The Supreme Court is deeply divided over questions about the limits on Congress’ legislative powers and about the extent to which states can assert sovereign immunity as a defense to claims under federal law. In these areas, and others, the two visions continue to clash.

Each can point to some support in the revered figures of history and our founding documents. Abraham Lincoln, in the Gettysburg address, dated the birth of the nation to 1776 and the Declaration of Independence, not 1788 and the Constitution. He consistently argued that the nation preceded the states, writing to Congress in 1861 that “The Union is older than any of the States and, in fact, it created them as States.”

Another Perspective

This essay is part of a discussion about the Supremacy Clause with Caleb Nelson, Emerson G. Spies Distinguished Professor of Law, University of Virginia School of Law. Read the full discussion here.

But was Lincoln right? It is true that the states acted collectively through a Congress before independence, but the Declaration of Independence talks of States taking their rightful place in the world, not of a single nation. Both the title and the last paragraph refer to “united States”—with the lowercase U suggesting that the phrase is not the name of a nation but simply a collection of, in the Declaration’s words, “Free and Independent States.”

The Constitution, likewise, tantalizes the supporters of each vision. The Preamble speaks of “We the People of the United States.” The U is capitalized, and that sounds like a single national body—until you dig deeper and learn that the original draft listed all thirteen states (“We the People of the States of New-Hampshire, Massachusetts, Rhode Island and Providence Plantations . . . ”) with the list eventually omitted for reasons of style and to avoid embarrassment if some states rejected the Constitution (as, indeed, Rhode Island initially did). Federalists, meanwhile, can point to the fact that in the Constitution, the phrase “United States” is always treated as a plural noun.

History gives us an answer of a sort. It shows a consistent flow of power from the states to the federal government—episodically, and typically in the face of at least temporary resistance by the Supreme Court, but consistently. This happens as a result of constitutional amendments—most notably the Reconstruction Amendments (the Thirteenth, Fourteenth, and Fifteenth), which both granted the federal government new powers and imposed new limits on the states, but also the Progressive-era amendments (the Sixteenth, Seventeenth, Eighteenth, and Nineteenth). And it happens as a result of Supreme Court acquiescence to expansive congressional claims of power, as happened during the time of the New Deal and also the Warren Court era.

Americans, in response, have generally changed their minds about the relative significance of the nation and the states. Most people consider their status as American citizens to be much more important than their state citizenship, and we now use “United States” as a singular noun. Still, even if the battle lines have shifted, the conflict between federalism and nationalism continues.

How does the Supremacy Clause relate to this persistent tension at the heart of the Constitution? It gives us at least one clear instance where nationalist values prevail. Within the scope of its powers, the federal government is supreme over the states. (Even here, though, people disagree—both about what the scope of those powers is, and about how to decide when an exercise of federal authority should displace state law.) But does the Supremacy Clause hold a general lesson about the respective status of the states and the federal government, pointing to broader federal supremacy? Or does it suggest to the contrary that whenever federal supremacy is not explicitly noted it does not exist? As always, the Constitution leaves some questions unanswered, open for debate and resolution by the American people.

Matters of Debate

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