The Supreme Court of the United States (SCOTUS) is the highest court in the federal judiciary of the United States. It has ultimate appellate jurisdiction over all federal court cases, and over state court cases that involve a point of U.S. Constitutional or federal law. The court consists of nine justices: the chief justice of the United States and eight associate justices, and the justices meet at the Supreme Court Building in Washington, D.C. . The U.S. Constitution does not specify the size of the Supreme Court, nor does it specify any specific positions for the courts members. However, the Constitution assumes the existence of the office of the chief justice, because it mentions in Article I, Section 3, Clause 6 that "the Chief Justice" must preside over impeachment trials of the President of the United States. The power to define the Supreme Courts size and membership has been assumed to belong to Congress, which initially established a six-member Supreme Court composed of a chief justice and five associate justices through the Judiciary Act of 1789. The number of Justices on the Supreme Court changed six times before settling at the present total of nine in 1869.

Therefore, the total strength of the Supreme Court of the United States is nine justices.