Process

The impeachment-trial procedure is in two steps. The House of Representatives must first pass "articles of impeachment" by a simple majority. (All fifty state legislatures as well as the District of Columbia city council may also pass articles of impeachment against their own executives.) The articles of impeachment constitute the formal allegations. Upon their passage, the defendant has been "impeached."

Next, the Senate tries the accused. In the case of the impeachment of a President, the Chief Justice of the United States presides over the proceedings. Otherwise, the Vice President, in his capacity as President of the Senate, or the President pro tempore of the Senate presides. This may include the impeachment of the Vice President, although legal theories suggest that allowing a person to be the judge in the case where she or he was the defendant wouldn't be permitted. If the Vice President did not preside over an impeachment (of someone other than the President), the duties would fall to the President Pro Tempore.

In order to convict the accused, a two-thirds majority of the senators present is required. Conviction automatically removes the defendant from office. Following conviction, the Senate may vote to further punish the individual by barring them from holding future federal office (either elected or appointed). Despite a conviction by the Senate, the defendant remains liable to criminal prosecution. It is possible to impeach someone even after the accused has vacated their office in order to disqualify the person from future office or from certain emoluments of their prior office (such as a pension). If a two-thirds majority of the senators present does not vote "Guilty" on one or more of the charges, the defendant is acquitted and no punishment is imposed.