Article III of the Constitution places the judicial power of the federal government in "one supreme Court, and in such inferior Courts" as the Congress might decide to establish. The Constitution grants the Supreme Court original jurisdiction in cases in which states are a party and those involving diplomats, but leaves for Congress to determine the size and responsibilities of the Court that is the capstone of the federal judiciary. The Judiciary Act of 1789 established a Supreme Court with one chief justice and five associate justices. The act further defined the jurisdiction of the Supreme Court to include appellate jurisdiction in larger civil cases and cases in which state courts ruled on federal statutes. Congress required the justices of the Supreme Court to preside with the local federal judges on the U.S. circuit courts that met in judicial districts throughout the nation, thus ensuring that members of the highest court would participate in the principal trial courts of the federal judiciary and be familiar with the procedures of the state courts.
The size of the Supreme Court grew to accommodate the establishment of new circuits as the nation expanded. In 1807 a seventh justice was added to the court, and in 1837 an eighth and ninth justice joined the Supreme Court. The size of the Court reached its highest point in 1863 with the creation of a Tenth Circuit on the west coast and the appointment of a tenth justice. In 1866, Congress reduced the size of the Court to seven justices and provided that no vacant seats be filled until that number was reached. The number of sitting justices fell to eight before an act of 1869 provided for nine justices, one for each of the judicial circuits established in 1866. The size of the Court has since remained the same.
The duties of circuit riding required the Supreme Court justices to spend most of their time traveling and prompted recurrent efforts to reduce or eliminate this responsibility. In 1793, Congress reduced the number of justices required to hold circuit court from two to one. In the Judiciary Act of 1801, Congress created separate circuit judgeships and freed the justices from any circuit court duties, but this exemption was short-lived. In 1802 Congress again assigned the justices to serve on the U.S. circuit courts, although it allowed the district judge to preside alone in some instances. The establishment of separate circuit judgeships in 1869 further relieved the circuit obligations of the justices. When Congress abolished the circuit courts in 1911, it finally made the justices' circuit duty optional.
Throughout its first century, the Supreme Court was responsible for deciding most civil appeals, and the justices had little control over a docket that was increasingly overcrowded. The act establishing the circuit courts of appeals in 1891 authorized the justices to grant review through certiorari and allowed the courts of appeals to certify other cases for appeal to the high Court at the same time that it restricted the right of automatic appeal to the Supreme Court. The Judges Bill of 1925 further increased the justices' discretion in determining what cases to hear, and in 1988 Congress eliminated almost all types of mandatory jurisdiction.
The Supreme Court has exercised only limited administrative authority over the federal courts. In 1922 the act creating the Conference of Senior Circuit Judges required the Chief Justice or an associate justice to convene the conference, and the Chief Justice continues to preside over the Judicial Conference. Congress in 1934 granted the Supreme Court responsibility for drafting rules of federal procedure. The 1939 law creating the Administrative Office of the U.S. Courts provided that the Supreme Court would appoint its director. Congress changed the law in 1990, vesting that authority in the Chief Justice, in consultation with the Judicial Conference. The Chief Justice also chairs the board of the Federal Judicial Center.