Article 3 of the U.S. Constitution creates the federal judiciary. It has three sections: Section 1 establishes the Supreme Court, authorizes Congress to create lower federal courts, and protects judges through lifetime tenure and salary guarantees; Section 2 defines what those courts can hear and requires jury trials in federal criminal cases; and Section 3 defines treason and strictly limits how it can be proved and punished.1Legal Information Institute. Article III – U.S. Constitution
Section 1: The Courts, the Judges, and Their Independence
Section 1 vests the judicial power of the United States in “one Supreme Court, and in such inferior Courts as the Congress may from time to time ordain and establish.”1Legal Information Institute. Article III – U.S. Constitution That single sentence does two very different things. It makes the Supreme Court mandatory. And it hands the entire architecture of the lower federal courts to Congress, to build and rebuild as it sees fit.
Congress moved almost immediately. The Judiciary Act of 1789 created the first district and circuit courts and fixed the Supreme Court at six justices.2Legal Information Institute. Judiciary Act of 1789 The number changed several times before settling at nine in 1869. Federal law now sets the Court at a Chief Justice and eight associates, with six needed for a quorum.3Office of the Law Revision Counsel. 28 USC 1 – Number of Justices; Quorum Article 3 itself never locks that number in, which is why proposals to enlarge or shrink the Court keep surfacing.
Good Behavior and Salary Protection
Judges appointed under Article 3 hold their seats “during good Behaviour.” In practice that means for life, unless they retire or are removed through impeachment.4Legal Information Institute. Good Behavior Clause – Overview The Framers borrowed the phrase from English law specifically to shield judges from political retaliation. A president who dislikes a ruling cannot fire the judge. A hostile Congress cannot vote the judge out.
Section 1 adds a second guarantee: a judge’s salary cannot be reduced while they remain in office.1Legal Information Institute. Article III – U.S. Constitution Without that, Congress could effectively force resignations by slashing pay. Together, life tenure and salary protection make Article 3 judges the most structurally independent officials in the federal government.
These protections apply only to Article 3 judges. Congress has created other federal courts under Article I, and the judges on those courts serve fixed terms without the same salary shield.5Constitution Annotated. Overview of Article III, Judicial Branch If you see a federal judge serving an eight- or fifteen-year term, that judge is not sitting in an Article 3 seat.
How an Article 3 Judge Can Be Removed
Impeachment is the only constitutional route. The House impeaches by majority vote, and the Senate then conducts a trial, with removal requiring a two-thirds vote of the members present. The grounds are the same as for any federal official: treason, bribery, or other high crimes and misdemeanors.6Legal Information Institute. Good Behavior Clause – Doctrine and Practice Across all of American history, the House has impeached 15 federal judges, and the Senate has convicted and removed eight of them.7Federal Judicial Center. Impeachments of Federal Judges The bar is deliberately high.
Section 2: What Federal Courts Can Hear
Section 2 defines the reach of the federal judicial power and limits it to “Cases” and “Controversies.” Federal courts do not answer hypothetical questions or issue advisory opinions, no matter how important the underlying legal issue.8Legal Information Institute. U.S. Constitution Annotated Article III Section II Clause I – Overview of Cases and Controversies Within that limit, they can hear disputes arising under the Constitution, federal statutes, and treaties; admiralty and maritime matters; cases involving the United States as a party; and controversies between citizens of different states.
Standing, Ripeness, and Mootness
Before a court considers the substance of any case, the plaintiff must show standing: an actual or threatened injury, fairly traceable to the defendant, that a favorable ruling would likely fix.9Legal Information Institute. Standing Requirement – Overview Miss any of the three and the case gets dismissed regardless of its merits. A surprising number of lawsuits end here.
Timing matters too. A suit filed before real harm has occurred can be dismissed as unripe. One that outlives its own controversy is dismissed as moot. The requirement of a live dispute runs through every stage of the litigation, not just the filing.10Legal Information Institute. Mootness Doctrine – Overview
Diversity Jurisdiction
One common path into federal court has nothing to do with federal law. When citizens of different states sue each other and more than $75,000 is at stake, the case can be heard in federal court.11Office of the Law Revision Counsel. 28 USC 1332 – Diversity of Citizenship; Amount in Controversy; Costs The point is neutral ground: a Texas plaintiff suing a California defendant in California state court might reasonably worry about home-court bias. The $75,000 threshold has been fixed since 1996 and is not adjusted for inflation.
Original and Appellate Jurisdiction of the Supreme Court
Section 2 also sorts the Supreme Court’s work into two categories. In a narrow set of cases, the Court sits as the trial court. This original jurisdiction covers cases involving ambassadors, other public ministers and consuls, and disputes where a state is a party.8Legal Information Institute. U.S. Constitution Annotated Article III Section II Clause I – Overview of Cases and Controversies When two states fight over a border or water rights, the Supreme Court is the only courtroom available.
Everything else reaches the Court on appeal. Article 3 gives Congress the power to make “Exceptions” and “Regulations” to that appellate authority, and under current law, review is almost entirely discretionary through writs of certiorari. The Court accepts roughly 60 to 80 cases per term out of thousands of petitions.12Office of the Law Revision Counsel. 28 USC 1257 – State Courts; Certiorari The justices tend to take cases where the federal appeals courts have split or where a constitutional question demands a national answer.
Criminal Jury Trials
Section 2 guarantees a jury trial for every federal criminal case except impeachment, and the trial must take place in the state where the crime was committed.13Legal Information Institute. Article III Section 2 Clause 3 – Jury Trials That location rule was meant to keep defendants near their witnesses and communities rather than moved somewhere hostile. When a crime occurs outside any state, such as on the open ocean, Congress designates where the trial happens.
A narrow exception exists for petty offenses, which could be tried without a jury at common law. Article 3 does not disturb that tradition. The Sixth Amendment later reinforced the criminal jury right with additional guarantees, and the Seventh Amendment separately preserves jury trials in federal civil suits at common law.14Legal Information Institute. Seventh Amendment
Section 3: Treason
Section 3 is the only place in the Constitution that defines a specific crime, and the definition is narrow on purpose. English kings had used treason charges to eliminate political opponents, and the Framers wanted to close that door in American law. Treason against the United States consists only in “levying War against them, or in adhering to their Enemies, giving them Aid and Comfort.”15Legal Information Institute. Treason Clause – Doctrine and Practice Criticizing the government, protesting policies, or holding unpopular views cannot be treason, however extreme.
The proof requirement is just as deliberate. Conviction requires either a confession in open court or the testimony of two witnesses to the same overt act.15Legal Information Institute. Treason Clause – Doctrine and Practice One person’s accusation is not enough. Two witnesses to different acts are not enough. That evidentiary standard makes treason one of the hardest crimes to prove in American law.
Punishment and Its Limits
Congress sets the penalty. Under current federal law, a treason conviction carries a minimum of five years in prison and a $10,000 fine, and a maximum of death, along with a permanent bar from holding federal office.16Office of the Law Revision Counsel. 18 USC 2381 – Treason
Section 3 then draws a hard line around how far that punishment can go. No treason conviction can “work Corruption of Blood, or Forfeiture except during the Life of the Person attainted.”17Constitution Annotated. Article III Section 3 Clause 2 The government cannot punish a traitor’s family. Children keep their inheritance, and descendants keep their property and civil standing. The punishment dies with the person convicted.
Judicial Review: The Power Article 3 Does Not Mention
Article 3 never expressly says federal courts can strike down laws that violate the Constitution. That power, judicial review, was established by the Supreme Court itself in the 1803 case Marbury v. Madison.18Legal Information Institute. Marbury v. Madison and Judicial Review Chief Justice John Marshall reasoned that the Constitution is the supreme law, that ordinary legislation conflicting with it cannot stand, and that deciding which law governs a case is “the very essence of judicial duty.” Every time a federal court blocks an executive order or invalidates a statute, its authority traces back to that opinion.
The power is not unlimited. Courts decline to resolve disputes the Constitution commits to the political branches. Foreign policy decisions, the internal procedures of Congress, and certain war-powers questions have been treated as political questions outside the judicial power granted by Article 3.