Article III of the Constitution is the part of the founding document that creates the federal judiciary. It establishes the Supreme Court, gives Congress the power to build lower federal courts beneath it, defines the categories of disputes those courts are allowed to hear, protects judges from political pressure through life tenure and guaranteed salaries, requires jury trials in federal criminal cases, and narrowly defines the crime of treason. Three short sections, drafted at the 1787 Constitutional Convention to fix the absence of a national court system under the Articles of Confederation, still govern how every federal court in the country operates.1Congress.gov. U.S. Constitution – Article III
What Article III Creates
Section 1 places all federal judicial power in “one supreme Court, and in such inferior Courts as the Congress may from time to time ordain and establish.”1Congress.gov. U.S. Constitution – Article III The Supreme Court is the only court the Constitution itself creates. Everything below it exists because Congress chose to build it.2Constitution Annotated. Establishment of Inferior Federal Courts
Congress first exercised that authority in the Judiciary Act of 1789, setting up district and circuit courts with carefully limited jurisdiction.3National Archives. Federal Judiciary Act (1789) The system has grown ever since. Ninety-four federal district courts now serve as trial courts, grouped into 12 regional circuits, each with a court of appeals. A thirteenth appellate court, the U.S. Court of Appeals for the Federal Circuit, handles specialized nationwide matters like patent cases.4United States Courts. About the U.S. Courts of Appeals The Supreme Court sits at the top as the final word on federal law.5United States Courts. Court Role and Structure
How Article III Protects Federal Judges
Judicial independence rests on two guarantees in Section 1. Federal judges hold office “during good Behaviour,” which in practice means a lifetime appointment. And their salaries cannot be reduced while they serve.1Congress.gov. U.S. Constitution – Article III No president can fire a federal judge for an unpopular ruling. No Congress can punish one through a targeted pay cut.6United States Courts. About the Supreme Court
The only route to removing an Article III judge runs through impeachment by the House of Representatives and conviction by the Senate. In more than two centuries, only eight federal judges have been impeached and removed, on charges ranging from tax evasion and perjury to disloyalty during the Civil War.7Federal Judicial Center. Impeachments of Federal Judges These protections apply only to Article III judges. Magistrate judges and bankruptcy judges, who are appointed for fixed terms under separate congressional authority, do not receive them.8United States Courts. Types of Federal Judges
What Cases Federal Courts Can Hear
Section 2 lists the categories of disputes federal courts are permitted to decide. Anything outside those categories belongs to the state courts. Two of the categories carry almost all of the day-to-day docket.
Federal Question Jurisdiction
Federal courts can hear any case “arising under this Constitution, the Laws of the United States, and Treaties.”1Congress.gov. U.S. Constitution – Article III If a dispute turns on a federal statute, a constitutional right, or an international treaty, a federal court has authority to decide it. The purpose is consistency. Without this category, the same federal law could mean different things in different states.
Diversity Jurisdiction
When the parties are citizens of different states and the amount in controversy exceeds $75,000, a federal district court can hear the case even if no federal law is at issue.9Office of the Law Revision Counsel. 28 USC 1332 – Diversity of Citizenship; Amount in Controversy; Costs The idea is to defuse home-court advantage. A Texas company sued in New York state court by a New York plaintiff may prefer a neutral federal forum. The dollar threshold keeps smaller disputes out of the federal system.
The Other Categories
Article III also extends federal judicial power to admiralty and maritime cases, disputes in which the United States itself is a party, conflicts between two or more states, cases involving ambassadors and other foreign officials, and suits between citizens of the same state claiming land under grants from different states.10Legal Information Institute. U.S. Constitution Article III The ambassador and maritime categories exist because foreign relations and international commerce are federal responsibilities, and inconsistent state rulings in those areas could create diplomatic trouble.
The Limits: “Cases” and “Controversies”
Even when a dispute falls inside one of the jurisdictional categories, Article III’s language limits federal courts to actual “cases” and “controversies.” That phrase has built up an entire body of law called justiciability doctrine, and it can shut a case down before the merits are ever reached.
Standing
To sue in federal court, a plaintiff must show three things: a concrete, actual injury; a causal link between that injury and the defendant’s conduct; and a likelihood that a favorable ruling would fix the problem.11Legal Information Institute. Lujan v. Defenders of Wildlife A generalized objection to government policy is not enough. Many would-be constitutional challenges fail here, not because the plaintiff is wrong on the law, but because the plaintiff cannot show a personal stake.
Ripeness and Mootness
Ripeness bars cases brought too early. If the alleged harm is speculative or hinges on future events that may never occur, federal courts will not intervene.12Constitution Annotated. Overview of Ripeness Doctrine Mootness bars cases brought too late. If the challenged law has already been repealed or the plaintiff’s injury has already been resolved, there is nothing left for a court to decide.13Constitution Annotated. Overview of Mootness Doctrine A live controversy has to exist from the filing of the complaint through the final ruling.
Political Questions
Some disputes are committed to Congress or the President by the Constitution itself, and federal courts will not decide them. The Supreme Court laid out the test in Baker v. Carr (1962), which looks at whether the issue is textually assigned to another branch and whether workable legal standards exist for resolving it.14Constitution Annotated. Overview of Political Question Doctrine Recognition of foreign governments and the conduct of impeachment proceedings are standard examples. When a court finds a political question, it dismisses the case for lack of jurisdiction even if standing, ripeness, and mootness are all satisfied.
How the Supreme Court Gets Its Cases
Article III splits the Supreme Court’s work into original and appellate jurisdiction, and the difference determines whether the justices are acting as a trial court or a reviewing court.
Original Jurisdiction
A small number of cases go directly to the Supreme Court without touching any lower court. The Court has exclusive original jurisdiction over disputes between two or more states, such as boundary fights and water-rights conflicts.15Office of the Law Revision Counsel. 28 USC 1251 – Original Jurisdiction It also has original but nonexclusive jurisdiction over cases involving ambassadors and foreign officials, disputes between the United States and a state, and suits by a state against citizens of another state. These matters are rare, amounting to only a handful per decade.
Appellate Jurisdiction and Certiorari
Almost every Supreme Court case arrives as an appeal from a lower federal court or a state supreme court. A losing party files a petition for a writ of certiorari, asking the justices to review the decision.16United States Courts. Supreme Court Procedures The Court receives roughly 7,000 to 8,000 petitions each term and grants oral argument in about 80. Under the informal “Rule of Four,” at least four of the nine justices must vote to accept a case before certiorari is granted. The justices typically choose cases that involve unresolved legal questions or where different circuits have reached conflicting conclusions. A denial of certiorari is not an endorsement of the lower court’s ruling; it just means the Supreme Court chose not to weigh in.
Judicial Review: The Power Article III Doesn’t Mention
The most consequential authority the federal courts exercise, the power to strike down laws that conflict with the Constitution, does not appear in Article III at all. The Supreme Court claimed it in Marbury v. Madison (1803), when Chief Justice John Marshall wrote that “a law repugnant to the Constitution is void” and that it is “emphatically the province and duty of the judicial department to say what the law is.”17Constitution Annotated. Marbury v. Madison and Judicial Review
That opinion turned Article III from a jurisdictional blueprint into the foundation of constitutional governance. Every major constitutional dispute since, from civil rights to campaign finance to the limits of executive power, has ultimately been resolved through the judicial review power Marshall established.18National Archives. Marbury v. Madison
The Jury Trial Guarantee
Article III, Section 2 requires that “the Trial of all Crimes, except in Cases of Impeachment, shall be by Jury.”19Constitution Annotated. Clause 3 – Trials The same clause requires that the trial be held in the state where the crime was committed, preventing the government from moving a defendant to a friendlier jurisdiction. When a federal crime occurs outside any state, Congress decides where the trial takes place.
The Sixth Amendment later strengthened this guarantee by requiring an impartial jury drawn from the state and district of the crime, and that right now applies to state prosecutions through the Fourteenth Amendment. But Article III’s jury trial clause is the original federal baseline, and it carves out the one exception the framers accepted: impeachment, which is tried by the Senate rather than a jury.
Treason
Treason is the only crime the Constitution itself defines. The framers wrote it into Article III because English monarchs had a long record of stretching the charge to punish political opponents, and the drafters wanted the definition beyond congressional reach. Section 3 limits treason to two things: waging war against the United States, or giving aid and comfort to its enemies.1Congress.gov. U.S. Constitution – Article III
The Two-Witness Rule
Conviction requires either two witnesses to the same overt act of treason or a confession in open court. No other federal crime carries this kind of built-in evidentiary threshold. The rule was designed to make convictions on rumor, single accusations, or secret testimony impossible.
Punishment and Corruption of Blood
Congress sets the penalty. Under current federal law, treason carries a minimum of five years in prison and a $10,000 fine, up to and including the death penalty, plus a permanent bar from federal office.20Office of the Law Revision Counsel. 18 USC 2381 – Treason Article III adds one more limit: no treason conviction may result in “corruption of blood.” That was the old English rule under which the descendants of a convicted traitor lost their inheritance rights and legal standing. The Constitution forbids it. Punishment falls on the convicted person and no one else.