The Tenth Amendment expresses the principle that undergirds the entire plan of the original Constitution: the national government possesses only those powers delegated to it, and “leaves to the several States a residuary and inviolable sovereignty over all other objects.” The Federalist No. 39. The Framers of the Tenth Amendment had two purposes in mind when they drafted it. The first was a necessary rule of construction. The second was to reaffirm the nature of the federal system.

Because the Constitution created a government of limited and enumerated powers, the Framers initially believed that a bill of rights was not only unnecessary, but also potentially dangerous. State constitutions recognized a general legislative power in the state governments; hence, limits in the form of state bills of rights were necessary to guard individual rights against the danger of plenary governmental power. The Constitution, however, conferred only the limited powers that were listed or enumerated in the federal Constitution. Because the federal government could not reach objects not granted to it, the Federalists originally argued, there was no need for a federal bill of rights. Further, the Federalists insisted that, under the normal rules of statutory construction, by forbidding the government from acting in certain areas, a bill of rights necessarily implied that the government could act in all other areas not forbidden to it. That would change the federal government from one of limited powers to one, like the states, of general legislative powers.

The Federalists relented and passed the Bill of Rights in the First Congress only after making certain that no such implication could arise from the prohibitions of the Bill of Rights. Hence, the Tenth Amendment (as well as the Ninth) enunciates a rule of construction that warns against interpreting the Bill of Rights to imply the existence of powers in the national government that were not granted by the original document.

That interpretative rule was vital because some of the provisions of the Bill of Rights purport to limit federal powers that are not actually granted by the original Constitution and thus might give rise to a (faulty) inference that the Bill of Rights implied the existence of such powers. The First Amendment, for instance, states that “Congress shall make no law . . . abridging the freedom of speech, or of the press.” Did that mean that the original Constitution had therefore granted Congress power to abridge those freedoms? The Federalists did not think so, which is why they initially opposed inclusion of a bill of rights. As Alexander Hamilton observed of the unamended constitutional text in The Federalist No. 84: “Here, in strictness, the people surrender nothing; and as they retain everything they have no need of particular reservations. . . . Why, for instance, should it be said that the liberty of the press shall not be restrained, when no power is given by which restrictions may be imposed?” Numerous other important figures made similar statements during the ratification debates. Obviously, the nation chose to include the Bill of Rights, but only with the Tenth Amendment as a bulwark against implying any alteration in the original scheme of enumerated powers. If Congress was not originally delegated power to regulate speech or the press, no such power is granted or implied by adoption of the Bill of Rights.

Despite the Framers’ concerns and the clear text of the Tenth Amendment, the Supreme Court indulged precisely this form of reasoning. In The Legal Tender Cases (1871), declining to locate the power to issue paper money in any enumerated power, the Court wrote:

And, that important powers were understood by the people who adopted the Constitution to have been created by it, powers not enumerated, and not included incidentally in any one of those enumerated, is shown by the amendments. . . . They tend plainly to show that, in the judgment of those who adopted the Constitution, there were powers created by it, neither expressly specified nor deducible from any one specified power, or ancillary to it alone, but which grew out of the aggregate of powers conferred upon the government, or out of the sovereignty instituted. Most of these amendments are denials of power which had not been expressly granted, and which cannot be said to have been necessary and proper for carrying into execution any other powers. Such, for example, is the prohibition of any laws respecting the establishment of religion, prohibiting the free exercise thereof, or abridging the freedom of speech or of the press.

This is precisely the kind of reasoning that the Tenth Amendment was designed to prohibit.

While providing a rule of construction for the relationship between the Bill of Rights and the scheme of enumerated powers, the Tenth Amendment also affirms the Constitution’s basic scheme of defining the relationship between the national and state governments. The Founders were wary of centralized government and were protective of the sovereignty of their individual states. At the same time, the failure of the Articles of Confederation revealed the necessity of vesting some authority independent of the states in a national government. The Constitution therefore created a novel system of mixed sovereignty. Each government possessed direct authority over citizens: the states generally over their citizens, and the federal government under its assigned powers. In addition, the states qua states were made a constituency within the national government’s structure. The state legislatures chose senators, determined how presidential electors should be chosen, and defined who would be eligible to vote for members of the House of Representatives. As noted in The Federalist No. 39, the new government was “in strictness, neither a national nor a federal Constitution, but a composition of both.” Critical to this mixed system were the limitations on the national government inherent in the scheme of enumerated federal powers, which allow the federal government to operate only within defined spheres of jurisdiction where it is acknowledged to be supreme. As Chief Justice John Marshall wrote in Marbury v. Madison (1803), “the powers of the [national] legislature are defined, and limited; and that those limits may not be mistaken or forgotten, the constitution is written.”

James Madison captured the essence of federalism in The Federalist No. 45:

The powers delegated by the proposed Constitution to the federal government are few and defined. Those which are to remain in the State governments are numerous and indefinite. The former will be exercised principally on external objects, as war, peace, negotiation, and foreign commerce . . . The powers reserved to the several States will extend to all the objects which, in the ordinary course of affairs, concern the lives, liberties, and properties of the people, and the internal order, improvement, and prosperity of the state.

The Tenth Amendment memorialized this constitutional solution of carefully enumerated, and thus limited, federal powers. Alexander Hamilton, urging ratification in New York, recognized in The Federalist No. 33 that congressional acts beyond its enumerated powers are “merely acts of usurpation” which “deserve to be treated as such.” And the Framers placed responsibility for resolving “controversies relating to the boundary” of the federal government’s enumerated powers squarely on the Supreme Court, for as Hamilton put it in the The Federalist No. 39, “[s]ome such tribunal is clearly essential to prevent an appeal to the sword and a dissolution of the compact.” Contrary to the command of the Tenth Amendment, the Supreme Court has not strictly confined the federal government to its enumerated powers.

The Tenth Amendment had limited judicial application in the nation’s first half century. No decision turned upon it, and in McCulloch v. Maryland (1819), Chief Justice Marshall declined an invitation to use it as a vehicle for narrowly construing federal powers. In the middle of the nineteenth century, the Tenth Amendment was cited in support of the doctrine of “dual federalism,” which maintained that the national and state governments were “separate and distinct sovereignties, acting separately and independently of each other, within their respective spheres.” Tarble’s Case (1872). Beginning with the New Deal Court, the Supreme Court has countenanced an expansion of federal powers far beyond the expectations of those who framed and ratified the Constitution. Because the Tenth Amendment is a textual reaffirmation of the scheme of enumerated powers, the modern expansion of the federal government’s role in national life has shaped, and diminished, the role of the Tenth Amendment in modern jurisprudence.

Modern Supreme Court decisions recognize few limits on the scope of Congress’s enumerated powers. Under current law, Congress may regulate, among other things, manufacturing, agriculture, labor relations, and many other purely intrastate activities and transactions. Indeed, in one case the Supreme Court upheld the power of Congress to regulate a single farmer’s production of wheat intended for consumption on his own farm. Wickard v. Filburn (1942). This expansive interpretation of Congress’s regulatory power under the Commerce Clause was based on the theory that because many farmers produce wheat for consumption on their own farms, such personal use, when viewed in the aggregate, has a substantial effect on interstate commerce in that commodity. The theory was applied more recently to uphold federal regulation of the home production and use of marijuana. Gonzalez v. Raich (2005).

The expansion of Congress’s commerce powers has generated federal-state conflicts that were not contemplated by the founding generation, such as federal regulation of state-government employment relations, federal use of state officials to enforce federal regulatory regimes, and direct federal commands to state agencies or legislatures. These conflicts call for interpretation of the relevant grants of federal power, most significantly the Commerce Clause, the Spending Clause, and the Necessary and Proper Clause (see Article I, Section 8). If the Constitution truly grants such expansive power to Congress, the Tenth Amendment’s terms are satisfied; if it does not, the Tenth Amendment is violated. That is the meaning of the often repeated statement of Chief Justice Harlan F. Stone in United States v. Darby (1941) that the Tenth Amendment is “but a truism that all is retained which has not been surrendered.”

In National League of Cities v. Usery (1976), however, the Supreme Court indicated that the Tenth Amendment carries some substantive protection of the states. In that case, the Court invoked the Tenth Amendment to prevent application of the Fair Labor Standards Act to state employees. Justice William H. Rehnquist’s opinion barred the federal government from transgressing upon the “functions essential to [a state’s] separate and independent existence,” activities taken as state qua state, which he regarded as protected by the Tenth Amendment’s reservation of powers to the states. National League of Cities overruled Maryland v. Wirtz (1968), an earlier case in which Justice William O. Douglas, joined by Justice Potter Stewart, had dissented because “what is done here is nonetheless such a serious invasion of state sovereignty protected by the Tenth Amendment that it is in my view not consistent with our constitutional federalism.”

The Court, in National League of Cities, embraced Justice William O. Douglas’s earlier dissent, but nine years later, in Garcia v. San Antonio Metropolitan Transit Authority (1985), the Court overruled National League of Cities. The language and reasoning of Garcia led many observers to think that the federal judiciary would no longer entertain federalism challenges to congressional exercises of power and that the states’ participation in the national political process would be their only protection against federal encroachments.

During the 1990s, that perception began to change, as the Supreme Court revived the Tenth Amendment to enforce discrete limits on congressional attempts to extend enumerated powers to state operations. The Rehnquist Court, for example, repeatedly curtailed Congress’s ability to “commandeer” the machinery of state government. In New York v. United States (1992), the Court prevented Congress from requiring a state legislature either to take care of the disposal of low-level radioactive waste or to take title to this hazardous material and be responsible for its safe disposal. In Gregory v. Ashcroft (1991), the Court noted the serious Tenth Amendment implications that would be raised by a congressional attempt to regulate the employment of state judges. And in Printz v. United States (1997), the Court barred Congress from requiring state executive officials to implement a federal scheme of firearms regulation. Outside of this context of direct federal control of state operations, however, the Court has made little direct use of the Tenth Amendment.

In two more recent decisions, in opinions written by Chief Justice John Roberts, the Supreme Court reaffirmed the sovereign dignity of the states. In United Haulers Ass’n v. Oneida-Herkimer Solid Waste Management Authority (2007), the Court held that the dormant Commerce Clause did not prevent a state from favoring its own waste treatment facility (even though it could not favor local private facilities) over out-of-state competitors. The Court held that trash disposal is the kind of “traditional governmental activity” that is immune from the restrictions of the dormant Commerce Clause. And in Shelby County v. Holder (2013), the Court struck down Section 4 of the Voting Rights Act of 1965, which operated to require certain states and voting districts to obtain preclearance from the Department of Justice before putting changes in voting procedures or districting into effect. Chief Justice Roberts opined that the federal government may not discriminate against the equal sovereignty of the states absent current evidence of a violation of federal law. Such discrimination against certain states was no longer warranted under current conditions.

Several other recent cases recognize minor limits on the scope of federal power without expressly relying upon the Tenth Amendment. United States v. Lopez (1995) and United States v. Morrison (2000) both struck down federal laws premised on an expansive application of the Commerce Clause—the regulation of guns in school zones (Lopez) and the creation of a federal civil remedy under the Violence Against Women Act (Morrison). The Court concluded that these statutes regulated activity that had nothing to do with “commerce” or any sort of economic enterprise, however broadly defined. In neither case (possessing a gun or committing “criminal acts motivated by gender bias”) was Congress regulating a commercial act. Possessing a gun may affect commerce but mere possession is not in itself a commercial act.

More recently, the Court recognized another limit on the scope of Congress’s power: the power to regulate commerce does not include the power to compel commerce. In National Federation of Independent Business v. Sebelius (2012), the Court (although it upheld the individual mandate as a tax) held that Congress exceeded its commerce power in enacting a statute requiring most Americans to purchase health insurance. Not buying something may affect commerce, but it is not a commercial act. The requirement, as the Court emphasized, “does not regulate existing commercial activity. It instead compels individuals to become active in commerce by purchasing a product.” To countenance such an exercise of congressional power would “fundamentally chang[e] the relation between the citizen and the Federal Government.” The “police power to regulate individuals as such, as opposed to their activities, remains vested in the States.” Given that the Tenth Amendment is a codification of the principle of enumerated federal power, those decisions implicate the Tenth Amendment, as does every decision involving the scope of federal power.

The recent decisions recognizing the Tenth-Amendment limitations on congressional power have been enormously controversial. But even assuming that our modern national economy permits (or requires) expansion of congressional authority well beyond its eighteenth-century limits, such expansion cannot extinguish the “retained” role of the states as limited but independent sovereigns. Thus, although Congress has broad power to regulate, and even to subject states to generally applicable federal laws, that power ends when it reaches too far into the retained dominion of state autonomy.