Article III of the Constitution: Federal Courts and Jurisdiction

Article III of the Constitution creates the federal judicial branch. It vests judicial power in one Supreme Court and any lower courts Congress chooses to establish, defines the kinds of disputes those courts may decide, protects judges through life tenure and salary guarantees, requires jury trials for federal crimes, and defines treason—the only crime spelled out in the Constitution itself.

What Article III Creates

Section 1 places all federal judicial power in “one supreme Court” and whatever lower courts Congress decides to create.¹ The Constitution does not fix the number of federal courts or how they should be organized. That responsibility belongs to Congress, which has reshaped the system repeatedly since the Judiciary Act of 1789.²

Today the federal system includes 94 district courts organized into 12 regional circuits, plus the Federal Circuit, which handles specialized appeals such as patent cases nationwide.³ District courts try cases. Courts of appeals review those trial decisions for legal errors. The Supreme Court has the final word on federal law.

What Federal Courts Can Hear

Federal courts are courts of limited jurisdiction. They can only hear the categories of cases listed in Article III, Section 2. Those categories fall into two groups: cases defined by their subject matter, and cases defined by who is involved.

Subject Matter

The broadest category covers cases “arising under” the Constitution, federal statutes, and treaties.¹ If a dispute turns on the meaning of a federal law or whether a constitutional right was violated, it belongs in federal court. Article III also extends judicial power to admiralty and maritime cases.

Diversity jurisdiction is the other main pathway. When a suit involves citizens of different states and the amount in controversy exceeds $75,000, a federal court can hear it even when no federal law is at issue.⁴ The point is to give parties a neutral forum. Once a case is properly in federal court, the court can also decide related state-law claims that grow out of the same dispute, a doctrine known as supplemental jurisdiction.⁵

Who the Parties Are

Article III also grants jurisdiction based on the parties. Federal courts handle cases involving ambassadors and foreign diplomats, cases where the United States itself is a party, and controversies between two or more states.¹ The Eleventh Amendment later narrowed this grant by barring individuals from suing a state in federal court without that state’s consent, a direct response to Chisholm v. Georgia (1793), where the Court allowed a South Carolina citizen to sue Georgia for unpaid debts.⁶

Original Versus Appellate Jurisdiction

Section 2, Clause 2 divides the Supreme Court’s work into two categories. The Court has original jurisdiction, meaning it hears a case first without any lower-court proceeding, in disputes between states and in cases involving foreign diplomats.⁷ Everything else reaches the Court on appeal. In practice, the Court controls its own docket through the certiorari process, and four of the nine justices must vote to hear a case before it is granted review.⁸

The Case or Controversy Limit

Article III restricts federal courts to actual “cases” and “controversies.” That phrase does a lot of work. It means federal courts cannot issue advisory opinions, decide hypothetical questions, or resolve disputes that have not yet harmed anyone. A controversy must be definite and concrete, with parties who have genuinely opposing legal interests.⁹

The most important doctrine flowing from this limit is standing. To sue in federal court, a plaintiff must show a real and concrete injury, a causal link between that injury and the defendant’s conduct, and a likelihood that a favorable ruling would redress the harm. The Supreme Court formalized this three-part test in Lujan v. Defenders of Wildlife (1992).¹⁰ Courts also apply ripeness, which bars decisions on disputes that have not fully developed, and mootness, which requires dismissal when a dispute has already been resolved.⁹

Judicial Review Is Not in the Text

Article III does not say federal courts can strike down a law as unconstitutional. That power, called judicial review, was established by the Supreme Court itself in Marbury v. Madison in 1803.¹¹ Chief Justice John Marshall reasoned that because the Constitution is the supreme law and federal courts decide cases arising under it, judges must determine whether a statute conflicts with the Constitution. If it does, the Constitution wins.

When a federal court declares a law unconstitutional, it nullifies that law regardless of which branch enacted it. Judicial review is the primary way Article III courts check the power of Congress and the President, even though the text of Article III never mentions it.

Judge Tenure, Pay, and Qualifications

To keep judges independent from the political branches that appoint and fund them, Article III includes two explicit protections. Federal judges serve “during good Behaviour,” which functions as a lifetime appointment.¹ The only way to remove one is impeachment. That is the point. A judge who cannot be fired for an unpopular ruling can follow the law without fearing the consequences.

Congress also cannot reduce a sitting judge’s pay.¹ That protection blocks lawmakers from retaliating economically against a judge for a decision they dislike.

One detail surprises most people. The Constitution sets no qualifications for federal judges. No age minimum, no citizenship requirement, no rule that a judge must be a lawyer or have attended law school.¹² Every requirement associated with the job, from legal experience to Senate confirmation, comes from tradition or statute rather than the constitutional text.

How Congress Checks the Courts

Article III leaves several levers in Congress’s hands. Congress decides which lower courts exist, how many judges sit on them, and how many justices serve on the Supreme Court. Those structural powers alone give Congress significant influence over the judiciary.

The Exceptions Clause in Section 2 goes further. It provides that the Supreme Court’s appellate jurisdiction is subject to “such Exceptions, and under such Regulations as the Congress shall make.” Congress has used this power to strip jurisdiction in politically charged moments. During Reconstruction, Congress repealed the statute authorizing certain habeas corpus appeals specifically to prevent the Court from ruling in Ex parte McCardle. The Court dismissed the case and acknowledged it had no power to question Congress’s motives.¹³

Congress controls the judiciary’s budget and holds the sole power to impeach and remove federal judges. Across American history, the House has impeached fifteen federal judges, and the Senate has convicted and removed eight.¹⁴

Jury Trials and Venue for Federal Crimes

Section 2, Clause 3 guarantees a jury trial in every federal criminal prosecution except impeachment.¹⁵ The Framers treated the jury as a shield between the individual and the government. Putting the power to convict in the hands of ordinary citizens keeps prosecutors and judges from acting alone to deprive someone of liberty.

The same clause requires that criminal trials take place in the state where the alleged crime occurred.¹⁵ That prevents the government from dragging a defendant to a distant jurisdiction where local sympathies might run against them. When a crime occurs outside the boundaries of any state, Congress can designate where the trial will be held. The Fifth and Sixth Amendments later added rights that expanded on these protections, including a speedy trial, the right to confront witnesses, and the right to counsel.

Treason: The Only Crime the Constitution Defines

The Framers wrote treason into the Constitution because in England the charge had been used as a political weapon against dissidents for centuries. Section 3 limits the crime to two acts: waging war against the United States, or supporting its enemies by giving them aid and comfort.¹⁶

The evidentiary bar is deliberately higher than for any other federal crime. Conviction requires either two witnesses to the same overt act, or a confession in open court.¹⁶ No hearsay, no secret testimony, no single witness. Federal law sets penalties ranging from a minimum of five years in prison and a $10,000 fine up to the death penalty, along with a permanent ban on holding federal office.¹⁷

Section 3 also bars Congress from imposing “corruption of blood,” an English practice under which a treason conviction stripped the offender’s descendants of inheritance rights and legal standing.¹⁶ Any forfeiture of property ends with the convicted person’s death. The punishment stays aimed at the offender, not the family.

1
Congress.gov. U.S. Constitution – Article III
2
The Avalon Project. 1 Stat. 73 – An Act to Establish the Judicial Courts of the United States
3
United States Courts. About the U.S. Courts of Appeals
4
Office of the Law Revision Counsel. 28 U.S. Code 1332 – Diversity of Citizenship; Amount in Controversy; Costs
5
Office of the Law Revision Counsel. 28 U.S. Code 1367 – Supplemental Jurisdiction
6
Congress.gov. U.S. Constitution – Eleventh Amendment
7
Congress.gov. Article III Section 2 Clause 2
8
Federal Judicial Center. The Supreme Courts Rule of Four
9
Congress.gov. ArtIII.S2.C1.1 Overview of Cases or Controversies
10
Legal Information Institute. Lujan v. Defenders of Wildlife, 504 U.S. 555
11
Congress.gov. ArtIII.S1.3 Marbury v. Madison and Judicial Review
12
Supreme Court of the United States. Frequently Asked Questions – General Information
13
Congress.gov. Exceptions Clause and Congressional Control over Appellate Jurisdiction
14
Federal Judicial Center. Impeachments of Federal Judges
15
Congress.gov. Article III Section 2 Clause 3
16
Congress.gov. U.S. Constitution Article III Section 3
17
Office of the Law Revision Counsel. 18 U.S.C. 2381 – Treason