impeachment, formal accusation issued by a legislature against a public official charged with crime or other serious misconduct. In a looser sense the term is sometimes applied also to the trial by the legislature that may follow. Impeachment developed in England, beginning in the 14th cent., as a means of trying officials suspected of dereliction of duty. The English procedure was for the House of Commons to prosecute by presenting articles of impeachment to the House of Lords, which rendered judgment. Any penalty, including death, might be inflicted. The impeachment (1787) and trial (1788-95) of Warren Hastings was among the last of the English cases.

In the United States impeachment of public officials is provided for in the federal government and in most states. In federal matters the U.S. Constitution gives the House of Representatives the power to impeach civil officers of the United States, including the President and Vice President, but not including members of Congress. Impeachments are tried by the Senate, with the concurrence of two thirds of the members present needed for conviction. The sole penalties on conviction are removal from office and disqualification from holding other federal office; however, the convicted party is liable to subsequent criminal trial and punishment for the same offense.

There have been 16 impeachments tried by the Senate and seven convictions. Three of the best-known cases, which did not result in conviction, were those of Supreme Court Justice Samuel Chase, President Andrew Johnson, and President Bill Clinton (see Lewinsky scandal). In 1974 the Judiciary Committee of the House of Representatives voted to bring impeachment charges against President Richard Nixon (see Watergate affair), but Nixon resigned before the House took action.

Criminal proceeding instituted against a public official by a legislative body. In the U.S. the president, vice president, and other federal officers, including judges, may be impeached by the U.S. House of Representatives. The House draws up articles of impeachment that itemize the charges and their factual bases. Once approved by a majority of House members, the articles are submitted to the Senate, which holds a trial. At its conclusion, each member votes for or against conviction on each article; conviction requires a two-thirds majority. A convicted official can be removed from office. The Constitution of the United States specifies that an officer is to be impeached for “high crimes and misdemeanors”; experts agree that impeachment is permitted for noncriminal misconduct (e.g., violation of the Constitution). Two U.S. presidents, Andrew Johnson and Bill Clinton, were impeached; both were acquitted. In 1974, articles of impeachment were drawn up against Pres. Richard Nixon, who resigned before formal proceedings could begin. In Britain, where the House of Commons prosecutes and the House of Lords judges impeachment proceedings, impeachment was formerly a means by which Parliament could get rid of unpopular ministers, usually court favourites protected by the monarch. The procedure fell into disuse in the early 19th century, when cabinet ministers became responsible to Parliament rather than to the sovereign.

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