Common Interpretation

Necessary and Proper Clause


The Constitution enumerates a great many powers of Congress, ranging from seemingly major powers, such as the powers to regulate interstate and foreign commerce, to seemingly more minor powers, such as the power to establish post offices and post roads. But there are many powers that most people, today or in 1788 (when the Constitution was ratified), would expect Congress to exercise that are not part of those enumerations. The Constitution assumes that there will be federal departments, offices, and officers, but no clause expressly gives Congress power to create them. Congress is given specific power to punish counterfeiting and piracy, but there is no explicit general authorization to provide criminal—or civil – penalties for violating federal law. Several constitutional provisions give Congress substantial authority over the nation’s finances, but no clause discusses a national bank or federal corporations.

These unspecified but undoubted congressional powers, and many others, emerge from the Clause at the end of Article I, Section 8, which gives Congress power “[t]o make all Laws which shall be necessary and proper for carrying into Execution” the other federal powers granted by the Constitution. This residual clause—called at various times the “Elastic Clause,” the “Sweeping Clause,” and (from the twentieth century onward) the “Necessary and Proper Clause”—is the constitutional source of the vast majority of federal laws. Virtually all of the laws establishing the machinery of government, as well as substantive laws ranging from antidiscrimination laws to labor laws, are enacted under the authority of the Necessary and Proper Clause. This Clause just might be the single most important provision in the Constitution.

At first glance (and keep in mind that first glances are not always last glances), close analysis of the words of the Necessary and Proper Clause suggests three criteria for a federal law to be within its scope: Laws enacted pursuant to the Clause must be (1) necessary, (2) proper, and (3) for carrying into execution some other federal power.

Historically, most of the controversy surrounding the meaning of the Necessary and Proper Clause has centered on the word “necessary.” In the 1790s during the Washington administration, and again two decades later in the Supreme Court, attempts to create a national bank in order to aid the nation’s finances generated three competing understandings of what kind of connection with another federal power makes a law “necessary” for implementing that power. Those understandings ranged from a strictly essential connection “without which the [implemented] grant of power would be nugatory” (Thomas Jefferson), to an intermediate requirement of “some obvious and precise affinity” between the implemented power and the implementing law (James Madison), to a very loose requirement allowing any law that “might be conceived to be conducive” to executing the implemented power (Alexander Hamilton).  In McCulloch v. Maryland (1819), the Supreme Court’s most famous case interpreting the Necessary and Proper Clause, the Court sided with Hamilton, giving Congress very broad authority to determine what is “necessary” for implementing federal powers. Subsequent cases have been at least as generous to Congress, finding necessity whenever one can imagine a “rational basis” for connecting implementing means to legislative ends. Indeed, no congressional law has ever been held unconstitutional by the Supreme Court on the stated ground that it was not “necessary” to implement a federal power.

Until quite recently, the word “proper” played no serious role in constitutional debates about the meaning of the clause. Indeed, a number of Founding-era figures, including such luminaries as Patrick Henry, James Monroe, and Daniel Webster, thought that the word “proper” was surplusage that added nothing to the word “necessary.” In 1997, however, following some academic commentary that sought to give substance to the requirement of propriety, the Supreme Court held in Printz v. United States that a federal law compelling state executive officials to implement federal gun registration requirements was not “proper” because it did not respect the federal/state boundaries that were part of the Constitution’s background or structure. Some later cases extended that holding to other matters involving federal/state relations. In NFIB v. Sebelius (2012), a constitutional challenge to “Obamacare,” the federal health care law, the Court sharply divided over whether a law could ever fail to be “proper” if it did not involve direct federal regulation of state governments or state officials. The subject is likely to be a point of contention in the future.

There was also little action until recently regarding what it means for a law to be “for carrying into Execution” another federal power. For a long time, the standard assumption has been that laws can carry federal powers into execution by making other laws grounded in those powers more effective. For example, the Court assumed in Missouri v. Holland (1920) that Congress could use the Necessary and Proper Clause to “carry[] into Execution” the treaty power by implementing and extending the substantive terms of a treaty. In recent years, however, three Justices have followed the lead of certain legal scholars by arguing that carrying the treaty power into execution means providing funds for ambassadors, pens and ink, and travel to foreign nations—in other words, it means making it possible to negotiate, draft, and ratify a treaty rather than to make the treaty more effective once it is negotiated, drafted, and ratified. Again, this subject is likely to be a point of contention in the future.

All of the foregoing, however, assumes that the right way to interpret the Necessary and Proper Clause is to pick apart its individual words and give each key term an independent meaning. That is not the only way to interpret the clause. Instead, one might look at the clause as a single, undifferentiated provision and try to discern the range of laws that the Clause, viewed holistically and purposively, tries to authorize.

One such vision (reflected in one of our separate statements) sees the Clause as a codification of principles of agency law that allow agents to exercise certain defined powers that are “incidental” to the main objects of the documents that empower the agents. Another such vision (reflected in the other of our separate statements) views the Clause as carrying forward ideas from a resolution adopted by the Constitutional Convention that would allow Congress to legislate “in all cases for the general interests of the Union . . . and in those to which the states are separately incompetent.” 

If the Necessary and Proper Clause has a relatively broad scope, as the second vision and two centuries of case law has largely maintained, it provides constitutional authorization for much of the existing federal machinery. If it has a narrower scope, as the first vision and a small but vocal group of Justices and scholars maintains, a great many federal laws that have been taken for granted for a long time might be called into question. The correct interpretation of the Necessary and Proper Clause might – just might – be the single most important question of American constitutional law.

Matters of Debate

The Necessary and Proper Clause and the Law of Agency


The Necessary and Proper Clause would have been familiar to Founding-era people from their everyday lives. Then, as today, people often designated agents to act on their behalves in various circumstances, ranging from selling goods overseas to managing farms to serving as guardians for minor children. The legal documents creating those agency relationships would expressly identify the main, or principal, powers to be exercised by the agents. Questions would naturally arise about whether the agents could exercise implied, or incidental, powers in carrying out their tasks. For example, could agents selling goods overseas agree to a sale on credit or could they only accept cash? Could someone charged with managing a farm lease it to a third party or even sell the farm outright if an attractive offer came along? A legal document could try to specify some of those incidental powers, but to anticipate every circumstance would be both hopeless and expensive. The obvious solution was a general clause outlining the scope of the agent’s incidental powers, informed by established customs and traditions setting baselines for the incidental powers of agents in different contexts.

The Necessary and Proper Clause, which gives Congress power to make “all Laws which shall be necessary and proper for carrying into Execution” other federal powers, is precisely this kind of incidental-powers clause. It was drafted by a Committee of Detail consisting of four practicing lawyers familiar with writing agency documents and a businessman familiar with applying them. The Clause’s language, which requires incidental congressional laws to be both “necessary and proper” in the conjunctive, was among the more restrictive or limited formulations for incidental powers available in the late eighteenth century, though it was more generous than the Articles of Confederation, which specifically forbade any incidental powers by authorizing the exercise only of powers expressly granted.

Several important conclusions follow from the agency-law origins and character of the Necessary and Proper Clause. First, the initial question for a law enacted under the Clause is not whether the law is necessary, proper, or for carrying into execution other federal powers. The initial question is always whether the law represents exercise of a truly incidental power or instead tries to exercise a principal power that would need to be specifically enumerated. In private law contexts, such questions were often informed by customs. By the late eighteenth century, for example, the power to manage a farm presumptively included as an incident the power to lease the farm, but it did not presumptively include the power to sell the farm. If you wanted to let an agent sell the farm, you needed to spell that out as a principal power in the document. Accordingly, under the Necessary and Proper Clause one must always ask whether Congress is trying to exercise, in the words of Chief Justice John Marshall from McCulloch v. Maryland in 1819, “a great substantive and independent power, which cannot be implied as incidental to other powers” or is instead employing “means not less usual, not of higher dignity, not more requiring a particular specification than other means.”

As is true with almost any plausible constitutional principle, applying the distinction between principal and incidental constitutional powers is not always easy.  It is a close question as a matter of original meaning, for example, whether Congress can incorporate a national bank as an incident to its enumerated financial powers. But some questions are easy. Congress can clearly create federal offices and impose penalties for violation of federal law as incidents to its principal powers. Congress just as clearly cannot use the Necessary and Proper Clause to force people to purchase products from others, as Congress did with the individual mandate in the Patient Protection and Affordable Care Act (“Obamacare”). The power to force people to transact with others is a “great substantive and independent power” – which is why the Constitution enumerates it as a principal power in a limited context by granting Congress express authority to “lay and collect Taxes.” Similarly, the power to hold someone over in prison after their sentence has run, at issue in United States v. Comstock  (2010), is patently a principal rather than incidental power. The power to regulate intra-state commerce, which grounds much of the modern federal regulatory regime, may also qualify as a principal power. If so, no amount of necessity, convenience, or helpfulness can turn a principal power into an incident.

Another Perspective

This essay is part of a discussion about the Necessary And Proper Clause with Neil S. Siegel, David W. Ichel Professor of Law and Professor of Political Science, Duke Law School. Read the full discussion here.

Second, even a power that is incidental to a principal power must be “necessary and proper for carrying into Execution” some other federal power. In the late eighteenth century, incidental powers were “necessary” when they were either indispensable, customary, or, in the words of the great eighteenth-century legal scholar William Blackstone, “so annexed to and so necessary to the well-being of the [principal power] . . . that they shall accompany . . . [the principal power] wherever it vests.” The Supreme Court’s Hamiltonian understanding of “necessary” as “convenient” or “rationally related to” is pretty plainly wrong. James Madison’s view that such laws must have an “obvious and precise affinity” with the principal power they implement much better captures the Founding-era conception of necessity in this context.

Third, laws under the Necessary and Proper Clause must be “proper.” That means, in essence, that they must conform to the standard duties of agents (what today we call “fiduciary” duties), which requires personal exercise of the power and conformance with duties of care, loyalty, and impartiality. The Necessary and Proper Clause thus reflects a principle of non-delegation, and it even grounds something resembling what today we call principles of equal protection (impartiality) and “substantive due process” (duties of care).

Further Reading:

For more detail on the claims in this statement, see Gary Lawson, Geoffrey P. Miller, Robert G. Natelson & Guy Seidman, The Origins of the Necessary and Proper Clause (2010), especially the two chapters by Rob Natelson, and Gary Lawson & David B. Kopel, Bad News for Professor Koppelman: The Incidental Unconstitutionality of the Individual Mandate, 121 Yale L.J. Forum 267 (2011).

Matters of Debate

The Necessary and Proper Clause and the Collective Action Principle


Article I, Section 8, is not a collection of unrelated legislative powers. Its clauses were initially drafted by the Committee of Detail, which had been instructed by the Philadelphia Convention of 1787 that Congress would have the authority “to Legislate in all Cases for the general Interests of the Union, and also in those Cases to which the States are separately incompetent.” That language suggests a background, or structural, principle of constitutional interpretation—the collective action principle—that can help in construing the clauses of Section 8. The collective action principle reflects the primary reason why the Framers created a national government with substantially more authority than it possessed under the Articles of Confederation.  See Robert D. Cooter & Neil S. Siegel, Collective Action Federalism, A General Theory of Article I, Section 8, 63 Stan. L. Rev. 115 (2010).

The Framers wrote Section 8 to address serious collective action problems facing the states during the 1780s. They especially wanted to protect the states from one another in the commercial sphere and from European powers in the military sphere. States acted individually when they needed to act collectively, discriminating against interstate commerce and free riding on the contributions of other states to the national treasury and military. Moreover, Congress lacked the power to address those problems. Section 8 gave Congress the power, including the authority to tax, regulate interstate commerce, raise and support a military, and “make all Laws which shall be necessary and proper for carrying into Execution the foregoing Powers, and all other Powers vested by this Constitution in the Government of the United States, or in any Department or Officer thereof.” 

That last power—the Necessary and Proper Clause—advances Section 8’s vision of effective collective action in three ways. First, the Clause underscores that Congress possesses the authority not just to directly solve collective action problems through use of its enumerated powers, but also to pass laws that do not themselves solve such problems but are convenient or useful to carrying into execution congressional powers that do. 

For example, regardless of whether an “individual mandate” to purchase health insurance itself solves collective action problems and is within the scope of the Commerce Clause, such a mandate is convenient for carrying into execution—that is, making more effective—clearly valid Commerce Clause regulations of health insurance companies, such as the prohibition on denying coverage to people with pre-existing conditions. Such a prohibition solves collective action problems by, for instance, dis-incentivizing insurance companies from moving to states that allow them to deny coverage to people with pre-existing conditions. Without federal intervention, a destructive “race to the bottom” might ensue, in which even states that preferred to protect residents with pre-existing conditions nonetheless allowed insurers to deny them coverage. 

A requirement to purchase insurance is convenient for carrying this valid Commerce Clause regulation into effect because it combats the perverse incentive people would otherwise have to wait until they became sick to purchase insurance. They would have such an incentive because federal law guarantees them access to health insurance even after sickness arises. With healthy people staying out of insurance markets and sick people filing claims, insurance premiums would increase substantially. The Necessary and Proper Clause underscores Congress’s power to ensure that its regulations will accomplish their objective of expanding—not reducing—access to affordable health insurance. The Supreme Court thus erred in NFIB v. Sebelius (2012), when it concluded 5-4 that the individual mandate in “Obamacare” was beyond the scope of the Necessary and Proper Clause.  See Neil S. Siegel, Free Riding on Benevolence: Collective Action Federalism and the Minimum Coverage Provision, 75 Law & Contemp. Probs., no. 3, 61-73 (2012).

Another Perspective

This essay is part of a discussion about the Necessary And Proper Clause with Gary Lawson, Philip S. Beck Professor of Law, Boston University School of Law. Read the full discussion here.

A second way in which the Necessary and Proper Clause advances the collective action principle is by allowing Congress to solve collective action problems when other federal powers are unavailable. For example, the question presented in United States v. Comstock (2010) was whether any clause of Section 8 authorizes Congress to permit the U.S. Attorney General to civilly commit mentally ill, sexually dangerous federal prisoners after they complete their federal sentences if no state will accept custody of them. The Court held 7-2 that the Necessary and Proper Clause confers such authority, relying in part on the fact that the case implicated a collective action problem involving multiple states.

The Court in Comstock recognized the “NIMBY” problem (“not in my backyard”). After the sentence of a sexually dangerous prisoner has expired, the federal government might release him for civil commitment in several possible states. A state (“State A”) that assumes custody must pay the financial costs associated with his indefinite commitment. Meanwhile, other states potentially benefit from State A’s decision to commit the individual, who might otherwise move to (or through) those states upon release in part because the federal government severed his ties to State A by imprisoning him for a long time. Instead of emphasizing that the federal government had helped create the problem it now sought to solve, the Court featured evidence that states often refuse to assume custody, potentially hoping to free ride on another state’s decision to do so. The Court stressed that the federal statute helps solve the collective action problem.

The discussion so far concerns the “federalism” component of the Necessary and Proper Clause—its effect on the relationship between the federal government and the states. The third way in which the Clause advances the collective action principle is through its “separation of powers” component—its effect on the relationship between Congress and the other branches. The part of the Clause that authorizes Congress “[t]o make all Laws which shall be necessary and proper for carrying into Execution . . . all other Powers vested by this Constitution in the Government of the United States, or in any Department or Officer thereof,” grants Congress broad authority to structure the executive and judicial branches. Thus, Congress decided “how many cabinet departments would fill the executive branch; how [they] would be shaped and bounded; how many justices would compose the Supreme Court; [and] where and when the Court would sit.”  Akhil Reed Amar, America’s Constitution: A Biography 111 (2005).

Under the Articles of Confederation, there was no separate Executive or Judiciary, and so federal law was largely unenforceable. Under the Constitution, Congress can ensure that federal laws—including solutions to collective action problems—are enforced effectively.

The separation of powers component confirms that Chief Justice Marshall, in McCulloch v. Maryland (1819), correctly interpreted the word “necessary” in the Necessary and Proper Clause to mean convenient or useful, not indispensable. Every creation or reorganization of federal departments throughout American history had to be “necessary” for carrying out powers granted to the federal government. Rather than being indispensable, each one was a convenient way of organizing the executive branch.  See Jack M. Balkin, Living Originalism 179 (2011).

A federal law is “proper”—or “appropriate,” in the language of McCulloch—if it is consistent with the constitutional text and structure. Federal legislation may not violate individual rights or contravene principles of separation of powers or federalism, including the collective action principle.

Matters of Debate

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