<P> Impeachment in the United States is the process by which the lower house of a legislature brings charges against a civil officer of government for crimes alleged to have been committed, analogous to the bringing of an indictment by a grand jury . At the federal level, this is done by the House of Representatives . Most impeachments have concerned alleged crimes committed while in office, though there have been a few cases in which officials have been impeached and subsequently convicted for prior crimes . The impeached official remains in office until a trial is held . That trial, and their removal from office if convicted, is separate from the act of impeachment itself . Analogous to a trial before a judge and jury, these proceedings are (where the legislature is bicameral) conducted by upper house of the legislature, which at the federal level is the Senate . </P> <P> At the federal level, Article I, Section 2, Clause 5 of the Constitution grants to the House of Representatives "the sole power of impeachment", and Article I, Section 3, Clause 6 grants to the Senate "the sole Power to try all Impeachments". In considering articles of impeachment, the House is obligated to base any charges on the constitutional standards specified in Article II, Section 4: "The President, Vice President, and all civil Officers of the United States shall be removed from Office on Impeachment for, and conviction of, Treason, Bribery, or other High Crimes and Misdemeanors". (Full text of clauses) </P>

Who has the authority to impeach a president