The Secretary of the Senate, and the assistant secretary thereof, shall, respectively, have power to administer any oath or affirmation required by law, or by the rules or orders of the Senate, to be taken by any officer of the Senate, and to any witness produced before it.
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2 U.S. Code § 24 - Secretary of Senate or assistant secretary may administer oaths
Statutory Notes and Related Subsidiaries
Change of Name
Assistant secretary of the Senate deemed successor in references to chief clerk of the Senate in all laws, rules, resolutions, and orders, effective July 1, 1971, under provisions of Pub. L. 92–51, July 9, 1971, 85 Stat. 125.