Constitution
Article III of the United States Constitution
Text from National Archives. Explanation last updated September 29, 2026. How we check this
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In plain English
Article III creates the judicial branch. It vests the judicial power in one Supreme Court and in lower courts Congress may establish, gives judges life tenure during good behavior, lists the kinds of cases federal courts may hear, and defines treason.
It says little about how the Supreme Court decides cases. The power of judicial review, courts declaring laws unconstitutional, was established by the Supreme Court in Marbury v. Madison (1803).
The text
As printed by the source cited at the end of this page, with its original spelling, capitalization and punctuation.
Section 1
The judicial Power of the United States, shall be vested in one supreme Court, and in such inferior Courts as the Congress may from time to time ordain and establish. The Judges, both of the supreme and inferior Courts, shall hold their Offices during good Behaviour, and shall, at stated Times, receive for their Services, a Compensation, which shall not be diminished during their Continuance in Office.
Section 2
The judicial Power shall extend to all Cases, in Law and Equity, arising under this Constitution, the Laws of the United States, and Treaties made, or which shall be made, under their Authority;—to all Cases affecting Ambassadors, other public Ministers and Consuls;—to all Cases of admiralty and maritime Jurisdiction;—to Controversies to which the United States shall be a Party;—to Controversies between two or more States;— between a State and Citizens of another State,—between Citizens of different States,—between Citizens of the same State claiming Lands under Grants of different States, and between a State, or the Citizens thereof, and foreign States, Citizens or Subjects.
In all Cases affecting Ambassadors, other public Ministers and Consuls, and those in which a State shall be Party, the supreme Court shall have original Jurisdiction. In all the other Cases before mentioned, the supreme Court shall have appellate Jurisdiction, both as to Law and Fact, with such Exceptions, and under such Regulations as the Congress shall make.
The Trial of all Crimes, except in Cases of Impeachment, shall be by Jury; and such Trial shall be held in the State where the said Crimes shall have been committed; but when not committed within any State, the Trial shall be at such Place or Places as the Congress may by Law have directed.
Section 3
Treason against the United States, shall consist only in levying War against them, or in adhering to their Enemies, giving them Aid and Comfort. No Person shall be convicted of Treason unless on the Testimony of two Witnesses to the same overt Act, or on Confession in open Court.
The Congress shall have Power to declare the Punishment of Treason, but no Attainder of Treason shall work Corruption of Blood, or Forfeiture except during the Life of the Person attainted.
Explained section by section
Section 1: courts and judges
The judicial power belongs to “one supreme Court” and to inferior courts that Congress may create. Judges hold office “during good behaviour,” which in practice means for life unless impeached, and their pay may not be reduced while in office. These protections aim to make judges independent of the other branches.
Section 2: what cases courts can hear
Federal judicial power extends to cases arising under the Constitution, federal laws and treaties; to ambassadors; admiralty and maritime cases; controversies in which the United States is a party; disputes between states; and cases between citizens of different states. The Eleventh Amendment later modified part of the text about suits against states.
The Supreme Court has original jurisdiction, meaning it hears a case first, only in a few categories such as those affecting ambassadors and those in which a state is a party. Otherwise it hears cases on appeal, subject to “such Exceptions, and under such Regulations as the Congress shall make.” Trials of all crimes except impeachment must be by jury.
Section 3: treason
Treason is defined narrowly as levying war against the United States or adhering to its enemies, giving them aid and comfort. Conviction requires the testimony of two witnesses to the same overt act or a confession in open court. The framers wrote a strict definition because accusations of treason had been used to punish political opponents. Congress sets the punishment, but it cannot “work Corruption of Blood.”
Context and current status
Federalist No. 78 argues that the judiciary is the “least dangerous” branch and defends life tenure as the guarantee of independence. Anti-Federalist writers, especially Brutus, warned that federal judges, unaccountable and protected by tenure, would expand their powers.
Current textual status: in force. The Eleventh Amendment modified the jurisdiction clause, and the number of Supreme Court justices, currently nine, is set by statute rather than by the Constitution.
Terms to know
- Judicial power
- The authority to decide cases and controversies and to issue binding judgments.
- Good behaviour
- The condition for holding federal judgeships; in practice, life tenure unless impeached and removed.
- Original jurisdiction
- Authority to hear a case at the start rather than on appeal.
- Appellate jurisdiction
- Authority to review decisions of lower courts.
- Corruption of Blood
- A historical punishment in which a traitor’s heirs lose the right to inherit.
Common misconceptions
“Article III says the Supreme Court can strike down laws.”
The text does not use the words “judicial review.” The Court claimed the power in Marbury v. Madison (1803), reasoning from the judicial duty to decide cases under the Constitution as supreme law.
“The Constitution sets the Supreme Court at nine justices.”
Article III says only “one supreme Court.” Congress has set the number by statute, and it has been nine since 1869.
How it connects
Links to related provisions and documents, with the reason each one matters here.
- Marbury v. MadisonMarbury v. Madison (1803)Marbury v. Madison is the decision in which the Court read Article III to include the power of judicial review.
- Federalist No. 78The Judiciary DepartmentFederalist No. 78 explains the framers’ reasoning for judicial independence and life tenure.
- Anti-Federalist No. 78-79Brutus XV on the Judiciary and Brutus XVI on the SenateBrutus XV and XVI warn about a judiciary that is independent of both the people and the legislature.
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Sources and corrections
- Text: National Archives. Checked against the source on September 29, 2026.National Archives transcription of the engrossed Constitution, with original spelling and capitalization. The signature block and the Convention's interlineation note are not reproduced.
- The Constitution of the United States: A Transcription — National Archives
- The Interactive Constitution: Article III — National Constitution Center
Educational material, not legal advice. Spotted a mistake? Tell us; corrections change this page’s update date.