The presiding officer, for the time being, of the Senate of the United States, shall have power to administer all oaths and affirmations that are or may be required by the Constitution, or by law, to be taken by any Senator, officer of the Senate, witness, or other person, in respect to any matter within the jurisdiction of the Senate.
Structure US Code
CHAPTER 2— ORGANIZATION OF CONGRESS
§ 22. Oath of President of Senate
§ 23. Presiding officer of Senate may administer oaths
§ 24. Secretary of Senate or assistant secretary may administer oaths
§ 25. Oath of Speaker, Members, and Delegates
§ 25a. Delegate to House of Representatives from District of Columbia
§ 26. Roll of Representatives-elect
§ 27. Change of place of meeting
§ 28. Parliamentary precedents of House of Representatives
§ 28c. Distribution of Precedents by Director of the Government Publishing Office
§ 29a. Early organization of House of Representatives
§ 30a. Jury duty exemption of elected officials of legislative branch