Answer:
Article III of the Constitution establishes the federal judiciary. Article III, Section I states that "The judicial Power of the United States, shall be vested in one supreme Court, and in such inferior Courts as the Congress may from time to time ordain and establish." Although the Constitution establishes the Supreme Court, it permits Congress to decide how to organize it. Congress first exercised this power in the Judiciary Act of 1789. This Act created a Supreme Court with six justices. It also established the lower federal court system.
Over the years, various Acts of Congress have altered the number of seats on the Supreme Court, from a low of five to a high of 10. Shortly after the Civil War, the number of seats on the Court was fixed at nine. Today, there is one Chief Justice and eight Associate Justices of the United States Supreme Court. Like all federal judges, justices are appointed by the President and are confirmed by the Senate. They, typically, hold office for life. The salaries of the justices cannot be decreased during their term of office. These restrictions are meant to protect the independence of the judiciary from the political branches of government.
Article III, Section II of the Constitution establishes the jurisdiction (legal ability to hear a case) of the Supreme Court. The Court has original jurisdiction (a case is tried before the Court) over certain cases, e.g., suits between two or more states and/or cases involving ambassadors and other public ministers. The Court has appellate jurisdiction (the Court can hear the case on appeal) on almost any other case that involves a point of constitutional and/or federal law. Some examples include cases to which the United States is a party, cases involving Treaties, and cases involving ships on the high seas and navigable waterways (admiralty cases).
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