What You Need to Know About the U.S. Constitution

The U.S. Constitution serves two essential roles:

• It establishes how our government works; and
• It guarantees certain freedoms and rights to every U.S. citizen.

Every American should understand the basics of the Constitution; however, much of it is written in archaic language from the 18th century, and even the more recent amendments can be hard to understand if you’re not a lawyer. This page is intended to explain the most important parts of the Constitution in plain language. For further information on the structure of the Constitution and how its provisions are interpreted by courts, see our main page on Constitutional Law.

The Constitution is made up of seven Articles and (currently) 27 amendments. The first three articles describe the three branches of government and outline their powers.

ARTICLE I—Congressional Structure and Powers

Article I of the U.S. Constitution describes the two houses of the legislature: the House of Representatives, whose numbers are based on the population of each state, and the Senate, in which representation is allocated equally. This form of legislature depends on two principles: the belief that people should choose their own representatives to enact their will in governing, and the tenet that laws should not be passed by temporary majorities. In practice, states enjoy both proportional representation and equal representation in the legislature. Each state elects congressional representatives apportioned to the number of districts in the state (which corresponds to the state’s population), but each state also elects two senators regardless of population. Article I gives these two legislative houses, known collectively as Congress, enumerated and implied powers.

Enumerated/Expressed Powers of Congress: these powers are listed specifically in Article I, Section 8. The powers delineated here include:

• the power to levy taxes and to determine how the revenue from those taxes should be spent in support of the country’s defense and general welfare;
• the power to borrow money; the power to regulate interstate commerce;
• the power to determine how immigrants can become citizens;
• the power to coin money and issue paper currency;
• the power to establish a postal system and its laws;
• the power to protect patents and copyrights;
• the power to establish a federal court system below the Supreme Court;
• the power to define and punish transgressions of maritime law;
• the power to declare war and to support an army and navy;
• the power to muster the states’ militias for the purpose of executing laws or suppressing rebellions; and
• the power to legislate the District of Columbia and any other federally owned land.

However, Article I, Section 8 ends with a provision that also grants Congress all powers that are “necessary and proper” to carry out its enumerated powers. This provision implies that Congress has powers not explicitly stated in the Constitution.

Implied Powers: Implied powers are not explicitly identified in the Constitution but have been extrapolated from the enumerated powers and thought to be necessary to implementing Congress’s express powers. The exact definition of implied powers has fluctuated considerably, but those powers include setting a minimum wage, borrowing money on behalf of the U.S., issuing patents and copyrights, maintaining the armed forces, and declaring war.

Inherent Powers: These powers are supposed to be encompassed by the very idea of a national government and include the power to control the country’s borders, to offer (or refuse) diplomatic recognition to other countries, and to acquire new territories.

ARTICLE II—Executive Branch

Article II of the Constitution establishes the executive branch of the government, headed by the President of the United States. The purpose of this branch is to carry out the government’s daily functions, to enter into treaties with other nations, to appoint federal judges and ambassadors, and to oversee the military. Article II also requires the President to periodically inform Congress about the state of the union.

ARTICLE III—Federal Judiciary

Article III provides for a federal judiciary, tasked with interpreting the laws of the United States. This article does not require a specific number of federal courts, nor does it explain how those courts should be organized. However, the article does establish a single Supreme Court as a court of last resort for legal cases that arise under the Constitution, U.S. laws, and treaties.

ARTICLES IV THROUGH VII

The remaining four original articles of the Constitution cover other essential properties of government and the Constitution’s role in governing the United States:

• ARTICLE IV—The States

  This article outlines the relationship between the federal government and the states, and between one state and another. The article provides that states shall respect the laws and judgments of other states.

• ARTICLE V—The Amendment Process

  This article confers the power to amend the Constitution. Amendment may be accomplished in two ways: two thirds of both houses of Congress propose an amendment, or two thirds of all state legislatures call a convention for the purpose of amending the Constitution. Amendments must be approved by three fourths of the states, either by state legislatures or in convention.

• ARTICLE VI—Legal Status of the Constitution

  This article establishes the Constitution as the law of the land and requires public officials to take an oath to uphold the Constitution and all laws stemming from it. This article also prohibits any religious test for holding public office.

• ARTICLE VII—Ratification

  This article ratifies the document.

The Bill of Rights

The first ten amendments to the Constitution are known collectively as the Bill of Rights. The Bill of Rights was drafted in response to calls from the states for greater freedom from federal control and was added to the Constitution to help ensure that the document would be ratified by the states. Many colonists had experienced the tyranny of the English monarchy before emigrating to the United States and wanted to be sure that the government in the new country would not engage in similar oppression. Many were fearful that the Constitution, as originally drafted, created a federal government with too much power. The Bill of Rights was intended to limit that power.

The Bill of Rights includes the first ten amendments to the U.S. Constitution:

• First Amendment—The First Amendment prohibits Congress from establishing an official religion or curtailing the free exercise of religion. It also establishes that Congress will not limit free speech, freedom of the press, or freedom of assembly.
  • Free Exercise of Religion: This clause of the First Amendment prohibits governmental regulation of religious beliefs and forbids the government from hindering religious observance or discriminating between religions. This clause has meant, for example, that a city could not pass laws against the killing of domestic animals where those laws were meant to restrict the practice of a religion that engaged in ritual sacrifices. However, cases litigating this clause often distinguish between freedom of belief and freedom of conduct. For instance, a series of cases in the late nineteenth century held that a federal law prohibiting polygamists from voting (a law that affected some Mormons in newly acquired territories) did not violate the Free Exercise Clause.
  • Free Expression: Generally, this right means that the government cannot prohibit an individual from expressing his or her beliefs or punish the individual for such expression. There are a few, defined limits on free speech – e.g., child pornography, defamation, inciting violence – but other types of expression, including offensive words and political protest, are protected.
  • Freedom of the Press: The First Amendment protects the press’s right to report news and state opinions without fear of censorship or other negative repercussions by the government. This freedom is not limited to traditional print journalism but has been extended to books, films, television broadcasts, and Internet content. A series of twentieth-century Supreme Court cases defined a broad freedom that protects the publication of even false information (except in some limited circumstances) and upheld the principle that the press should not be subject to prior restraints, meaning that if a newspaper acquires publishable information, the government cannot pass a law to restrict its publication.
  • Freedom of Assembly: The First Amendment guarantees the right to “peaceable” assembly, allowing groups to gather, share, and exchange ideas. However, this right is not absolute: the government may impose restrictions on the time, place, and manner of assembly.
• Second Amendment—The Second Amendment explicitly states that the right to “keep and bear arms” shall not be abridged. While the Amendment refers to a “well-regulated militia,” the Supreme Court has clarified that the right extends to individual gun ownership (District of Columbia v. Heller, 554 U.S. 570 (2008)).
• Third Amendment—The Third Amendment has been litigated less than any other part of the Bill of Rights for reasons that may seem obvious: this Amendment provides that no soldiers will be quartered in private homes during peacetime without the owners’ consent. Between 2013 and 2017, this Amendment received some attention as the basis for claims meaning to combat the use of surveillance, or the use of private homes for police stakeouts (see, e.g. Mitchell v. City of Henderson). However, none of the cases arguing that police should be seen as “military” for purposes of a Third Amendment claim has succeeded.
• Fourth Amendment—The Fourth Amendment states that “the right of the people to be secure in their persons, houses, papers, and effects, against unreasonable searches and seizures, shall not be violated, and no warrants shall issue, but upon probable cause.” This Amendment establishes the requirement for search warrants and limits the ability of police to conduct stop-and-frisk searches, among other things.
• Fifth Amendment—The Fifth Amendment is a kind of omnibus, creating certain rights for defendants in civil and criminal trials. Among the protections carved out by this amendment are the following:
  • The right against self-incrimination: a defendant cannot be compelled to testify against himself.
  • Prohibition on double jeopardy: a defendant cannot be tried twice for the same crime.
  • Due process of law must be followed in any proceeding that could deprive someone of life, liberty, or property.
  • Criminal defendants have the right to a grand jury investigation for federal felonies.
  • The government must compensate a property owner for taking any property.

  For further information on the provisions of the Fifth Amendment, see our page on 5th Amendment Law.

• Sixth Amendment—The Sixth Amendment enumerates several rights for criminal defendants, including the right to a speedy and public trial, the right to an impartial jury, the right to know the nature of the charges against them, the right to know and confront opposing witnesses, the right to call witnesses to testify on their behalf, and the right to have the assistance of counsel. For more detailed information on the rights afforded to a criminal defendant by the Sixth Amendment, see our separate page on that topic.
• Seventh Amendment—The Seventh Amendment the right to trial by jury in federal civil matters, unless the parties to the controversy waive that right.
• Eighth Amendment—The Eighth Amendment contains several provisions governing criminal trials, but probably its best-known prohibition forbids “cruel and unusual punishments,” a prohibition generally discussed in the context of capital punishment. This Amendment also prohibits excessive bail and excessive fines.
• Ninth Amendment—The Ninth Amendment keeps the door open to other rights: this Amendment provides that the rights granted by the Constitution are not limited to only those rights that are specifically enumerated in the Bill of Rights.
• Tenth Amendment—The Tenth Amendment articulates the fundamental principle of federalism: those powers not delegated to the United States by the Constitution, nor prohibited by it to the states, are reserved to the states.

OTHER IMPORTANT AMENDMENTS

There are 27 amendments to the Constitution. Some of these amendments clarify procedures (such as how the Electoral College meets and votes) while others clarify rights. Some of the most important amendments are the Thirteenth, Fourteenth, Sixteenth, and Nineteenth Amendments.

The Thirteenth Amendment

The Thirteenth Amendment, which was passed by the House of Representatives in January 1865 and ratified by the states later that year, abolished slavery and involuntary servitude except as punishment for a crime. That exception means that prisoners who are duly convicted of a crime can be forced to labor without pay.

The Fourteenth Amendment

The Fourteenth Amendment, which was ratified in 1868, offers a guarantee of several important rights and protections, including Equal Protection and Due Process.

The Equal Protection Clause ensures that the government treats its citizens in the same way, or at least does not treat citizens differently for impermissible reasons. For example, the government may treat a citizen who has committed a crime differently than it treats citizens who have not committed a crime, but it may not treat citizens of a particular religion or race differently from other citizens. For further information on how the Supreme Court applies the Equal Protection Clause, see our page on that topic.

The Due Process Clause of the 14th Amendment has been applied by the Supreme Court to uphold substantive rights such as the right to work, the right to use contraception, and the right to marry. It also ensures that a state cannot deprive an individual of life, liberty, or property without notice and a fair hearing. The Fifth and Fourteenth Amendments to the U.S. Constitution both contain Due Process Clauses. The Due Process Clause of the Fifth Amendment pertains to federal government action and the Fourteenth Amendment’s applies to state and local government action.

The Citizenship Clause defines U.S. citizenship to include all persons born or naturalized in the United States. The immediate effect of this clause was to confirm that the descendants of African slaves were also citizens. More recently, this clause has been invoked to uphold “birthright citizenship,” the principle that children born within the U.S. are citizens of the U.S. even if their parents are not.

The Privileges and Immunities Clause of the 14th Amendment repeats the guarantee of the Fourth Amendment that “the citizens of each state shall be entitled to all privileges and immunities of citizens in the several states.” The clause has not been extended to specific rights afforded by individual states, but only to fundamental rights, like life, liberty, property ownership, and safety.

The Sixteenth Amendment

The Sixteenth Amendment, ratified in 1913, gave Congress the ability to levy a federal tax on citizens’ incomes.

The Nineteenth Amendment

The Nineteenth Amendment extended the right to vote to women.