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.