Article I, United States Constitution

Article I of the United States Constitution defines the structure and powers of the US Congress. The Framers of the Constitution believed that the heart of a government should be the legislature. The United States was to be governed by law, and Congress was to be the sole source of the laws. It was not an accident that the very first words of the Constitution, Article I, Section 1, are: “All legislative powers herein granted shall be vested in a Congress of the United States, which shall consist of a Senate and House of Representatives.”

In every period of American history, there have been great political and legal struggles swirling around the Congress. These issues can be subsumed under three major headings: congressional structure, national powers, and federalism. Structural issues have to do with such questions as the selection of members, bicameralism, and relationships with the other branches of the government. Controversies over the extent and nature of congressional powers are always present. The necessary and proper and commerce clauses of Article I, Section 8, in particular have been repeatedly discussed, analyzed, and tested from the earliest days of the Republic to the twenty-first century. Federalism issues have to do with the balance and sometimes conflicting roles of the state and national governments. As with national powers, there have been controversies over the federal balance since the establishment of the Constitution. There is no reason to suspect that this pattern won't continue indefinitely into the future.


The US Congress, as Article I, Section 1, states, is bicameral. Bicameral means that it consists of two branches or “chambers” whose members have a different representational basis and hence are differently selected. The organizational rules for Congress are set forth in Article I, Sections 2 through 7.

The larger of the two bodies is the House of Representatives. Each state is allocated a number of representatives roughly proportional to the state's population. The total number of representatives was frozen at 435 by statute in 1911 lest population growth make the body so large as to become unwieldy. Its members are chosen by elections from single-member districts whose boundaries are established by state law. Up until 1964, electoral districts could vary widely in population. This resulted in substantial overrepresentation of rural voters. The famous US Supreme Court case Reynolds v. Sims, 377 U.S. 533 ( 1964 ), established the “one-person, one-vote” principle by forcing state governments to establish electoral districts with equal or nearly equal numbers of voters.

Representatives serve a term of two years before they have to stand for reelection, but it is not uncommon for members to remain in office for twenty or even thirty years if they come from relatively noncompetitive political districts. Moreover, state governments have become expert at gerrymandering, that is, drawing up district lines that divide the voters for a disfavored party so as to keep that party from winning seats in the biennial elections.

The second house is the US Senate. Each state chooses two senators. Up until the passage of the Seventeenth Amendment in 1913, senators were elected by state legislatures; since then, they have been popularly chosen in statewide elections. Each senator serves a sixyear term; the terms are staggered so that in any given election year about a third of the seats in the Senate are up for election.

The powers of each house of Congress differ slightly from those of the other. The Senate has the sole power to ratify treaties and to approve presidential appointments; the House of Representatives is the originating house for all tax and spending measures. The House has the exclusive power to impeach members of the executive and judicial branches of the government. Impeach, in this context, means accuse. A bill of impeachment is the equivalent of an indictment in ordinary criminal law. The Senate then has the sole power to try an individual whom the House has impeached. Two American presidents have been impeached—Andrew Johnson ( 1808–1875 ) and Bill Clinton ( b. 1946 )—but neither was convicted. Had President Richard Nixon ( 1913–1994 ) not resigned in 1974 he would have been impeached and convicted for covering up a variety of illegal activities associated with the Watergate scandal. Conviction by the Senate results only in being ousted from office. Fifteen federal judges have been impeached. Three resigned before trial, eight were convicted, and four were acquitted.

Other than the differences mentioned above, the House and Senate operate together under a bicameral arrangement. Nothing becomes law in the United States unless it has been approved by both houses of Congress. Since senators and representatives spring from quite different political constituencies, the proposals that do become law must pass the scrutiny of both houses and tend to reflect the convictions of the political center— that is, of concurrent majorities. Should it turn out, as it did, for example, during most of President Barack Obama's ( b. 1961 ) terms in office, that the ideological gulf between House and Senate is too wide, the bicameralism requirement can lead to political paralysis or stasis.

Every bill that passes both houses of Congress is subject to the presentment requirement. Presentment means that a bill passed by both houses must be sent to the president for approval. The president is given ten days to act. He can sign the bill, and it becomes law. If he does nothing, the bill becomes law without his signature after the ten days. And if the president objects to the bill—that is, vetoes it—it can go back to Congress. If two-thirds in each house reapprove the bill, it becomes law. If not, the bill is dead.


Section 8 of Article I sets forth the powers of the federal government. All the great powers of sovereignty but one are granted to the US government: it may lay and collect taxes; coin, borrow, and spend money; regulate interstate commerce and foreign trade; provide for military defense, make war, and enter into diplomatic relations; and establish post offices and roads. These powers, as well as some lesser ones, are set forth in Article I. What the Framers denied to the federal government is what is known as the police power. The police power is the general power to safeguard the life, health, and property of the inhabitants of the country. In the United States, a federal system, the Framers left the police power to state governments. Thus, for example, there is no constitutionally provided federal power to make burglary a crime.

The powers and activities of the federal government have increased enormously since the Constitution was ratified. This has come about partly through the US Supreme Court's broad construction of federal powers and its application of the necessary and proper clause to the federal government's enumerated powers, such as the power to regulate interstate commerce. The process began with McCulloch v. Maryland, 17 U.S. 316 ( 1819 ). This case tested the meaning of the necessary and proper clause: “To 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” (Art. I, Sec. 8, cl. 18).

In the early nineteenth century, there were two theories of the American Republic. The first, the states' rights theory, was that the Republic was a compact between sovereign states. Under this notion, the powers of the federal government should be viewed narrowly so as not to infringe on the powers of the states. The necessary and proper clause is interpreted to mean that the federal government may pass only those laws that are absolutely necessary to implement the explicitly granted national powers of Article I.

The second view was that both the national government and the states are supreme within their respective spheres. This is the principle that the Court adopted. Chief Justice John Marshall ( 1755–1835 ) wrote the opinion for a unanimous Court. He pointed out that the Constitution was established by the whole people of the United States, as stated in the Preamble, and that the Constitution itself is full of provisions that restrict state sovereignty. McCulloch defines the reach of the federal powers broadly but with boundaries or criteria laid out as follows: “Let the end be legitimate, let it be within the scope of the Constitution, and all means which are appropriate, which are plainly adapted to that end, which are not prohibited, but consist with the letter and spirit of the Constitution, are constitutional” (17 U.S. at 421). Since the end of the Civil War in 1865, this view of federal powers has completely prevailed.

Chief Justice Marshall applied the principle of broad construction to Congress's power to regulate interstate commerce (Art. I, Sec. 8, cl. 3) in Gibbons v. Ogden, 22 U.S. 1 ( 1824 ). Those who favored a narrow or “strict” construction of federal powers argued that interstate commerce consisted only of the transportation of goods across state lines. Marshall decided on a broader construction: “Commerce undoubtedly is traffic, but it is something more: it is intercourse. It describes the commercial intercourse between nations, and parts of nations, in all its branches, and is regulated by prescribing rules for carrying on that intercourse” ( 22 U.S. at 189–90 ). The Court fended off the argument that a conflicting New York State law should prevail by defining the commerce power as “the power to regulate; that is, to prescribe the rule by which commerce is to be governed. This power, like all others vested in Congress, is complete in itself, may be exercised to its utmost extent, and acknowledges no limitations, other than are prescribed in the Constitution” (22 U.S. at 196). The decision in Gibbons explicitly excluded from interstate commerce the “internal commerce of a state.”

As thus formulated, the great question became whether any particular activity was interstate or intrastate commerce. For nearly one hundred years after Gibbons, the Supreme Court's decisions dealt only rarely with this issue. Under the Court's decisions, mining and manufacturing were considered local. It was only with the Progressive reform movement of the early twentieth century and with the Great Depression that began in 1929 that federal laws attempted to reach economic activities that would have been considered local during the nineteenth century. Federal power under the commerce clause began to expand. By 1942, the expansion reached a peak. In Wickard v. Filburn, 317 U.S. 111 ( 1942 ), the Supreme Court said “Even if appellee's activity be local and though it may not be regarded as commerce, it may still, whatever its nature, be reached by Congress if it exerts a substantial economic effect on interstate commerce, and this irrespective of whether such effect is what might at some earlier time have been defined as ‘direct’ or ‘indirect’” (317 U.S. at 125).

Since Wickard, the expansion of Article I power under the commerce clause has resulted in the passage of many federal laws regulating activities that in earlier times would have been considered to have fallen only within the police power of the individual states. The most striking of these laws was the Civil Rights Act of 1964, which, among other things, prohibited racial or religious discrimination in employment and places of public accommodation. The statute was upheld in Heart of Atlanta Motel v. United States, 379 U.S. 2141 ( 1964 ). In other cases, the federal government was able to reach issues of air, water, and general environmental quality, extortionate credit transactions (that is, “loan sharking”), and workplace safety, all without demurrer by the Supreme Court. It appeared that the United States was moving in the direction of empowering the federal government with a general police power under the commerce clause of Article I.

In 1995, the trend was halted. In 1990, Congress had passed the Gun-Free School Zones Act. A section of this law made it a federal offense for “any individual knowingly to possess a firearm at a place the individual knows, or has reasonable cause to believe, is a school zone.” Alfonso Lopez, a twelfth-grade student at a San Antonio high school, was convicted for carrying a concealed pistol on school grounds. The Supreme Court reversed his conviction, holding that Congress had exceeded its authority under the commerce power.

Chief Justice William Rehnquist ( 1924–2005 ), writing for the majority in United States v. Lopez, 514 U.S. 549 ( 1995

The four dissenters in the case argued, in effect, that education, broadly construed, “affects” interstate commerce. But the dissenters could not suggest activities that would not fall under the commerce clause, thus establishing a general federal police power. In arguing the case, counsel for the government was also unable to do so. United States v. Lopez, and a subsequent case holding unconstitutional a federal statute that criminalized rape, has, at least for the moment, brought a halt to federal police power regulations under the commerce clause.

While the commerce clause has been the most fertile source of federal law, some of the other clauses of Article I, Section 8, have also resulted in substantial exercises of federal power. The war power of clause 11 authorizes Congress to declare war. The power to wage war, according to the Supreme Court, is “the power to wage war successfully” ( Korematsu v. United States, 323 U.S. 214 [1944] ). It carries with it the power to conscript soldiers, ration goods, control wages and prices, and, as in Korematsu, intern people believed to be dangerous to the war effort.


Together with Section 8, the last two parts of Article I, Sections 9 and 10, establish the dimensions of federalism in the United States. A federal system of government is one in which authority and functions are divided between a general government, referred to as the federal or national government in the United States, and constituent governments, known as state governments in the United States. The federal government is supreme in its sphere. Section 9 places limits on the sphere by forbidding certain powers to the federal government; Section 10 does the same for state governments. As one would expect, all federal systems are prone to jurisdictional conflicts between the general and constituent governments. The United States is no exception.

Before addressing questions of federalism, the first clauses of Section 9 contain some important guarantees of civil liberty. The federal government is forbidden to suspend the writ of habeas corpus except in wartime or time of rebellion. This most vital guarantee means that all imprisonment or detention by the government is subject to review by the courts; in the absence of “probable cause,” an individual cannot be held. This provision of the Constitution was first tested during the Civil War when President Abraham Lincoln ( 1809–1865 ) temporarily suspended the writ. The detention of suspected terrorists at Guantanamo Bay in the years after the World Trade Center attacks of September 11, 2001, has also raised the issue. In both of those emergency situations, executive and legislative power seems to have prevailed.

Clause 3 forbids Congress to pass any bills of attainder. A bill of attainder is a law that imposes punishment on a named individual or group. In other words, Congress may not fine, imprison, or kill individuals. It may only define crimes. The guilt or innocence of individuals is tested by trial in court. Ex post facto laws are also forbidden to Congress. An ex post facto (literally, “after the fact”) statute seeks to punish people for an offence that took place before the law was passed.

The civil liberties guarantees of Article I, Section 9, were deemed insufficient by the public when the Constitution was ratified; amendments were proposed by the first Congress. Ten of these were ratified by the states and became what is today called the Bill of Rights.

The remainder of Section 9 deals explicitly with federalism concerns. National taxes must be apportioned among the states by population so as to prevent Congress from favoring or disfavoring particular states or regions by taxing them differently. In Article VIII of the Constitution this clause is tied in to the “three-fifths” compromise: slaves were to be counted at three-fifths in reckoning population numbers. Both the apportionment provision and the three-fifths compromise were overtaken by events, the former by the passage of the Income Tax Amendment (Amendment XVI), and the latter by the end of slavery.

Clauses 5 and 6 prevent Congress from taxing exports and from giving preferences (that is, in import duty rates) to the ports of any state over those of the others. For example, in the absence of these provisions, Congress could tax, say, the export of apples, hay, lumber, and airplanes from Washington State. That would ruin the state. The same kind of thing could occur with discriminatory import duties. If Japanese automobile imports were taxed at 10 percent on arrival at California ports and 6 percent at Oregon ports, the economic outcome would be obvious. State economic activities get a level playing field, at least so far as federal commerce and taxing regulations are concerned.

Watercolor of Broad Street, Wall Street, and City Hall, later known as Federal Hall, New York City, by John Joseph Holland, 1797. New York served as the seat of the Confederation Congress (1785–1788) and the First Federal Congress (1789–1790).

Watercolor of Broad Street, Wall Street, and City Hall, later known as Federal Hall, New York City, by John Joseph Holland, 1797. New York served as the seat of the Confederation Congress (1785–1788) and the First Federal Congress (1789–1790).

The final provision of Article, I Section 9, forbids Congress from granting titles of nobility. Although little notice is taken of this limit on federal power and no litigation has resulted from it, it serves as a reminder that the Framers of the Constitution and the people who ratified it did not want an aristocracy to be established. This is consistent with the words of the Declaration of Independence, that “All men are created equal.” The United States was to be a republic, not a monarchy, and was not to have an aristocracy.

Section 10 is the concluding portion of Article I. In many ways, it is analogous to Section 9. It places limits on state powers, most of which are calculated to prevent state governments from interfering with the sphere of federal power, and particularly with the powers most closely linked to national sovereignty.

As with Section 9, the first clause mixes civil liberty guarantees with federal concerns. Like the federal government, states are forbidden to pass ex post facto laws or bills of attainder or to grant titles of nobility. But this clause also forbids the states from establishing their own currencies, making treaties or agreements with foreign nations, or passing laws “impairing the obligation of contracts.”

Some of these provisions are obvious and self-explanatory. If there is to be one country, it must have a uniform currency and uniform foreign policy. The states are taken out of the foreign policy and money-coining businesses.

Some of the other limits were designed to curb pernicious abuses that took place before the establishment of the Constitution when the United States was under the Articles of Confederation. States would attempt to control by state law the exchange rates between their own currencies and those of their neighbors. This practice brought interstate trade nearly to a complete standstill. States passed laws impairing the obligation of contracts—that is, bankruptcy laws—which allowed their own residents to be discharged of debts owed to people or businesses in other states.

The third clause supplements the first by forbidding states to make war or keep troops unless they have been actually invaded. The provision ties in with arrangements for the establishment and governance of the militia, whose rules are established by the states until Congress decides to step in.

The states are also forbidden to enter into agreements with other states or a foreign nation without the consent of Congress. This limit is designed to keep states from forming mutual assistance leagues whose purpose is to establish regional advantages of some kind for their own commerce. As it happens, Congress has been fairly permissive. There are many issues whose solution really does require interstate cooperation. Such interstate compacts or agreements as the Port Authority of New York and New Jersey, the Colorado River Compact, and the Delaware River Basin Commission are all established with Congress's consent. The Supreme Court has also been permissive, ruling that states can form interstate agreements without congressional consent as long as those agreements do not decrease federal power.


A good argument can be made that Article I of the Constitution is the heart of the American constitutional enterprise. It establishes the Congress itself, empowers and limits it, controls its relationships with the other branches of the government and with the states, and incorporates a rudimentary set of civil and political rights. Although the presidency has become the political center of the American government, Congress remains the constitutional center.

SEE ALSO Congress as a Governing Institution ; Constitution ; Federal Powers: General ; Federalism in American History ; McCulloch v. Maryland; Separation of Powers .


Corwin, Edward S. Edward S. Corwin's The Constitution and What It Means Today. Revised by Harold W. Chase and Craig R. Ducat. 14th ed. Princeton, NJ: Princeton University Press, 1978.

Galloway, George B. The Legislative Process in Congress. New York: Crowell, 1953.

Hamilton, Alexander, James Madison, and John Jay. The Federalist Papers. (1788.) Edited by Clinton Rossiter and Charles R. Kesler. New York: Signet, 2003.

Kurland, Philip B., and Ralph Kurland, eds. The Founders' Constitution. Chicago: University of Chicago Press, 1987.

Robert Jacobs
Central Washington University