His LYING UNDER OATH was the impeachment. The subject matter was related to his adultery, but the impeachment was for LYING ABOUT IT WHILE UNDER OATH.
Impeachment Law & Legal Definition
Impeachment may refer to different legal concepts. One meaning in the law refers to discrediting a witness by showing that he or she is not telling the truth or does not have a reliable basis for their testimony. Rules of evidence govern what type of questioning may be used to impeach a witness. Generally, unrelated evidence that the person is a" bad person" and therefore untrustworthy, is not allowed.
Impeachment also refers to the trial of a public official for charges of illegal acts committed in the performance of public duty. It is the constitutional process, not the conviction or removal from office, whereby the House of Representatives may "impeach" (accuse of misconduct) high officers of the federal government for trial in the Senate.
What Does It Mean to Impeach? | eHow
Constitutional Provision
According to Article II, Section 4 of the U. S. Constitution, "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." Article I, Section 3 spells out the roles played by the House of Representatives and the Senate.
Role of the House of Representatives
The impeachment process starts in the judiciary committee of the House of Representatives, which decides whether to authorize an investigation. If enough evidence of crime is uncovered, articles of impeachment are sent to the full House of Representatives, where the articles must pass with a majority vote.
Role of the Senate
After House approval, the articles of impeachment go to the Senate, which acts as a jury for a trial prosecuted by the House of Representatives. Conviction requires a two-thirds affirmative vote by the Senate members present.
Historic Impeachments
Though articles of impeachment have been filed against nine U.S. presidents, only two presidents, Andrew Johnson and William Clinton, have been brought to trial. In 1868, Johnson avoided impeachment by just one vote. Clinton survived his 1999 impeachment trial by a vote of 55-to-45. In 1974, President Richard Nixon chose to resign from office before official proceedings were underway.
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Clinton was impeached by the House but survived the vote in the Senate.