The following sections of the U.S. Constitution have direct bearing on the Impeachment of the President of the United States:
Article I
Section 3
6. The Senate shall have the sole Power to try all impeachments. When sitting for that purpose, they shall be on Oath of Affirmation. When the President of the United States is tried, the Chief Justice shall preside: And no person shall be convicted without the Concurrence of two thirds of the Members present.
7. Judgment in Cases of impeachment shall not extend further than to removal from Office, and disqualification to hold and enjoy any Office of honor, Trust or Profit under the United States: but the party convicted shall nevertheless be liable and subject to Indictment, Trial, Judgment and Punishment, according to Law.
Article II
Section 2
5. The House of Representatives shall choose their Speaker and other Officers; and shall have the sole Power of Impeachment.
Section 4
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, and other high crimes and Misdemeanors.