In the United States, presidential impeachment is decided by a majority vote in the House of Representatives. Impeachment shows that the House of Representatives believes that the president has committed a crime.
After impeachment takes place, the president stands trial at a hearing before the Senate. The president has lawyers to present his side of the case, and knowledgeable members of the House of Representatives present the opposition. The Chief Justice of the U.S. Supreme Court presides over the trial. The U.S. Senate hears the evidence and takes on the role of jury. A two-thirds vote by the Senate is required to remove the president from office.