The United States Judiciary Act of 1789 (ch. 20, 1 Stat. 73-93) was a landmark statute adopted on September 24, 1789 in the first session of the First United States Congress establishing the U.S. federal judiciary. Article III, section 1 of the Constitution prescribed that the "judicial power of the United States, shall be vested in one Supreme Court", and such inferior courts as Congress saw fit to establish. It made no provision, though, for the composition or procedures of any of the courts, leaving this to Congress to decide.

The existence of a separate federal judiciary had been controversial during the debates over the ratification of the Constitution. Anti-Federalists had denounced the judicial power as a potential instrument of national tyranny. Indeed, of the ten amendments that eventually became the Bill of Rights, five (the Fourth through the Eighth) dealt primarily with judicial proceedings. Even after ratification, some opponents of a strong judiciary urged that the federal court system be limited to a Supreme Court and perhaps local admiralty judges. The Congress, however, decided to establish a system of federal trial courts with broader jurisdiction, thereby creating an arm for enforcement of national laws within each state.

Details of the Act

The Act set the number of Supreme Court justices at six: one Chief Justice and five Associate Justices. The Supreme Court was given exclusive original jurisdiction over all civil actions between states, or between a state and the United States, as well as over all suits and proceedings brought against ambassadors and other diplomatic personnel; and original, but not exclusive, jurisdiction over all other cases in which a state was a party and any cases brought by an ambassador. The Court was given appellate jurisdiction over decisions of the federal circuit courts as well as decisions by state courts holding invalid any statute or treaty of the United States; or holding valid any state law or practice that was challenged as being inconsistent with the federal constitution, treaties, or laws; or rejecting any claim made by a party under a provision of the federal constitution, treaties, or laws.

The Act also created 13 judicial districts within the 11 states that had then ratified the Constitution (North Carolina and Rhode Island were added as judicial districts in 1790, and other states as they were admitted to the Union). Each state comprised one district, except for Virginia and Massachusetts, each of which comprised two. Massachusetts was divided into the District of Maine (which was then part of Massachusetts) and the District of Massachusetts (which covered modern-day Massachusetts). Virginia was divided into the District of Kentucky (which was then part of Virginia) and the District of Virginia (which covered modern-day West Virginia and Virginia).

This Act established a circuit court and district court in each judicial district (except in Maine and Kentucky, where the district courts exercised much of the jurisdiction of the circuit courts). The circuit courts, which comprised a district judge and (initially) two Supreme Court justices "riding circuit," had original jurisdiction over serious crimes and civil cases of at least $500 involving diversity jurisdiction or the United States as plaintiff. The circuit courts also had appellate jurisdiction over the district courts. The single-judge district courts had jurisdiction primarily over admiralty cases, petty crimes, and suits by the United States for at least $100. Notably, the federal trial courts had not yet received original federal question jurisdiction.

Congress authorized all people to either represent themselves or to be represented by another person. The Act did not prohibit paying a representative to appear in court.

Congress authorized persons who were sued by citizens of another state, in the courts of the plaintiff's home state, to remove the lawsuit to the federal circuit court. The power of removal, and the Supreme Court's power to review state court decisions where federal law was at issue, established that the federal judicial power would be superior to that of the states.

The Act created the office of Attorney General, and also provided for the appointment of a marshal, one or more deputy marshals, and a United States Attorney for each judicial district.

A clause granting the Supreme Court the power to issue writs of mandamus outside its appellate jurisdiction was declared unconstitutional by Marbury v. Madison 5 U.S. 137 (1803), one of the seminal cases in American law. Thus, the Judiciary Act of 1789 was the first act of Congress to be partially invalidated by the Supreme Court.

The Judiciary Act of 1789 included the Alien Tort Statute, now codified as , which provides jurisdiction in the district courts over lawsuits by aliens for torts in violation of the law of nations or treaties of the United States.