The American court system was established in accordance with Article III of the U.S. Constitution, which created the judicial branch of the United States government. The U.S. Congress passed the Judiciary Act of 1789, establishing the Supreme Court and the circuit courts.
The Judiciary Act dictated that the Supreme Court should consist of a chief justice and five associate justices. The Supreme Court was granted jurisdiction over large civil cases as well as cases in which federal statutes dictate rulings. During the early stages of its development, the Supreme Court exercised little control over which cases it heard, but began reviewing cases after 1891. The Supreme Court gained authority over federal courts in 1934.
The Judiciary Act also set up three circuit courts divided into geographical areas. The purpose of the circuit courts was to decide cases between citizens of different states, cases involving most federal crimes, and civil cases brought by the federal government. Circuit courts also functioned as appellate courts. As the population of the United States grew, the number of Supreme Court justices and circuit courts increased. The circuit courts stopped hearing appeals in 1891, when the U.S. Court of Appeals was established.
The juvenile court system emerged almost a century after the judicial system began. Between 1880 and 1920, an increase in urbanization contributed to the growth in criminal activities among children, leading to development of the juvenile court system.