United States Chief Justice

Chief Justice of the United States
Incumbent John Roberts since September 29, 2005
Style	The Honorable (formal) Mr. Chief Justice (informal) Your Honor (when addressed directly in court)
Appointer	Presidential nomination with Senate confirmation
Term length	Life tenure
Constituting instrument	U.S. Constitution
Inaugural holder	John Jay as Chief Justice of the Supreme Court September 26, 1789
Formation	March 4, 1789

The Chief Justice of the United States is the chief judge of the Supreme Court of the United States. As such, he is head of the United States federal court system, which functions as the judicial branch of the nation's federal government. The Chief Justice is one of nine Supreme Court justices; the other eight have the title Associate Justice.

The Chief Justice, as the highest judicial officer in the country, serves as a spokesperson for the federal government's judicial branch, and acts as a chief administrative officer for the federal courts. He is also head of the Judicial Conference of the United States, and in that capacity appoints the director of the Administrative Office of the United States Courts. By law, he is also a member of the Board of Regents of the Smithsonian Institution, and by custom is elected chancellor of the board.

The Chief Justice leads the business of the Supreme Court and presides over oral arguments. When the court renders an opinion, the Chief Justice—when in the majority—decides who writes the court's opinion. The Chief Justice also has significant agenda-setting power over the court's meetings. In the case of an impeachment of a President of the United States, which has occurred twice, the Chief Justice presides over the trial in the U.S. Senate. Additionally, the presidential oath of office is typically administered by the Chief Justice (although the Constitution does not assign this duty to anyone in particular).