The attorney general is nominated by the President of the United States and takes office after confirmation by the United States Senate. He or she serves at the pleasure of the president and can be removed by the president at any time; the attorney general is also subject to impeachment by the House of Representatives and trial in the Senate for “treason, bribery, and other high crimes and misdemeanors.”
The office of Attorney General was established by Congress by the Judiciary Act of 1789. The original duties of this officer were “to prosecute and conduct all suits in the Supreme Court in which the United States shall be concerned, and to give his advice and opinion upon questions of law when required by the president of the United States, or when requested by the heads of any of the departments.”[1] Only in 1870 was the Department of Justice established to support the attorney general in the discharge of his responsibilities.
http://en.wikipedia.org/wiki/United_States_Attorney_General
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