DEFINITION of Impeachment

Impeachment is the formal process of bringing charges against a high-ranking government official, in a bid to remove him or her from office. In the United States, the President, Vice President, and all civil officers are subject to impeachment for impeachable crimes defined as “treason, bribery, or other high crimes misdemeanors”; the exact definition of these crimes remains ambiguous. Impeachment at the federal level is a rare occurrence, with the U.S. Senate having conducted formal impeachment proceedings only 19 times in its long history.

Impeachment does not imply that removal from office is a certainty, but since it is the first step in the process of such ejection, the term “impeachment” is often erroneously interpreted as removal itself.


The power of U.S. Congress to impeach officials of the federal government, all the way up to the President, is an essential part of the constitutional system of checks and balances. The framers of the U.S. Constitution who created the office of a powerful President with a fixed term of office also included the impeachment mechanism as a safeguard in case things went disastrously wrong.

Only the U.S. House of Representatives has the power to impeach a federal official, and only the Senate can convict and remove such an impeached official. The House investigates whether impeachment charges are warranted against a civil officer of the federal government. If the House determines that charges are justified, it draws up articles of impeachment that specify the charges against the officer, and votes on these articles. If the articles of impeachment are approved by a simple majority of the House members, they are then submitted to the Senate – thus formally impeaching the officer – which organizes itself into a court, with the Senate Chamber serving as the courtroom.

The Senate now becomes judge and jury, except in the case of presidential impeachment trials, when the chief justice of the United States presides. The House appoints a committee of representatives called “managers” to act as prosecutors before the Senate, and the impeached officer forms the defense. When the trial concludes, Senate members vote on each individual article of impeachment. The Constitution requires a guilty verdict from two-thirds of the Senate for a conviction, for which the penalty is removal from office and in some cases, disqualification from holding any future federal office. Congress has no power to impose criminal penalties such as imprisonment of impeached officials.

History of Federal Impeachment Proceedings

Of the 19 federal impeachment proceedings since 1799, only six have occurred in the 80 years preceding September 2017. Impeached officials included 14 judges, two Presidents, a Senator, Justice, and Secretary of War. These impeachments resulted in seven acquittals, eight convictions, three dismissals and one resignation with no further action.

Only two U.S. Presidents have been impeached by the House – Andrew Johnson and Bill Clinton – and both were acquitted by the Senate. President Richard Nixon was never impeached, although he was threatened with impeachment over the Watergate scandal of 1974. Nixon stepped down before Congress could vote on whether to proceed with impeachment, becoming the only U.S. President to have resigned from office.