42 U.S. Code § 10264 - Investigatory powers
Upon request of the Chairman or a majority of the members of the Board, the Board may hold such hearings, sit and act at such times and places, take such testimony, and receive such evidence, as the Board considers appropriate. Any member of the Board may administer oaths or affirmations to witnesses appearing before the Board.
(b) Production of documents
(1) Upon the request of the Chairman or a majority of the members of the Board, and subject to existing law, the Secretary (or any contractor of the Secretary) shall provide the Board with such records, files, papers, data, or information as may be necessary to respond to any inquiry of the Board under this subchapter.