Final answer:
During an impeachment trial of the U.S. President, the Chief Justice of the Supreme Court presides over the proceedings in the Senate. For the President to be removed from office, a two-thirds majority in the Senate must vote for conviction.
Step-by-step explanation:
If an effort to impeach the President of the U.S. is made, the Chief Justice of the Supreme Court presides at the trial. This process begins in the House of Representatives where charges of impeachment are brought forth. The Senate, vested with the sole Power to try all Impeachments, acts as the jury during a presidential impeachment trial.
It's important to note that for a President to be removed from office following the trial, a two-thirds majority vote by the Senators present is required. This balances the impeachment process with a high threshold for conviction, ensuring that such a decision reflects broad legislative consensus.
Presidential impeachments are rare historical events, with instances including the trials of Presidents Andrew Johnson and Bill Clinton, both of whom were acquitted as the Senate did not reach the necessary two-thirds majority for conviction.