<P> According to federal statute, the Court normally consists of the Chief Justice of the United States and eight associate justices who are nominated by the President and confirmed by the Senate . Once appointed, justices have lifetime tenure unless they resign, retire, or are removed from office . Each justice has a single vote in deciding the cases argued before it; the chief justice's vote counts no more than that of any other justice . However, the Chief Justice--when in the majority--decides who writes the court's opinion . Otherwise, the senior justice in the majority assigns the writing of a decision . In modern discourse, the justices are often categorized as having conservative, moderate, or liberal philosophies of law and of judicial interpretation . While a far greater number of cases in recent history have been decided unanimously, decisions in cases of the highest profile have often come down to just one single vote, thereby exposing the justices' ideological beliefs that track with those philosophical or political categories . The Court meets in the Supreme Court Building in Washington, D.C. Its law - enforcement arm, the United States Marshals Service, is under the oversight of the U.S. Department of Justice . </P> <P> It was while debating the division of powers between the legislative and executive departments that delegates to the 1787 Constitutional Convention established the parameters for the national judiciary . Creating a "third branch" of government was a novel idea; in the English tradition, judicial matters had been treated as an aspect of royal (executive) authority . Early on, some delegates argued that national laws could be enforced by state courts, while others, including James Madison, advocated for a national judicial authority consisting of various tribunals chosen by the national legislature . It was also proposed that the judiciary should have a role in checking the executive power to exercise a veto or to revise laws . In the end the Framers of the Constitution compromised by sketching only a general outline of the judiciary, vesting of federal judicial power in "one supreme Court, and in such inferior Courts as the Congress may from time to time ordain and establish ." They delineated neither the exact powers and prerogatives of the Supreme Court nor the organization of the Judicial Branch as a whole . </P> <P> The 1st United States Congress provided the detailed organization of a federal judiciary through the Judiciary Act of 1789 . The Supreme Court, the country's highest judicial tribunal, was to sit in the nation's Capital, and would initially be composed of a Chief Justice and five associate justices . The act also divided the country into judicial districts, which were, in turn, organized into circuits . The justices were required to "ride circuit," and hold circuit court twice a year in their assigned judicial district . </P> <P> Immediately after signing the Act into law, President George Washington nominated the following people to serve on the Court: John Jay for Chief Justice; plus John Rutledge, William Cushing, Robert H. Harrison, James Wilson, and John Blair Jr. as associate justices . All six were confirmed by the Senate on September 26, 1789 . Harrison, however, declined to serve . In his place, Washington later nominated James Iredell . </P>

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