In case of refusal to obey a subpena served upon any person under this section, the district court of the United States for any district in which such person is found, resides, or transacts business, upon application by the Attorney General at the request of the Secretary and after notice to such person, shall have jurisdiction to issue an order requiring such person to appear and give testimony before the Secretary or to appear and produce documents before the Secretary. Any failure to obey such order of the court may be punished by such court as contempt thereof and subject to a penalty of up to $10,000 a day.
30 U.S. Code § 1717 - Hearings and investigations
(a) Authorization; affidavits, oaths, subpenas, testimony, and payment of witnessesIn carrying out his duties under this chapter the Secretary may conduct any investigation or other inquiry necessary and appropriate and may conduct, after notice, any hearing or audit, necessary and appropriate to carrying out his duties under this chapter. In connection with any such hearings, inquiry, investigation, or audit, the Secretary is also authorized where reasonably necessary—
to pay witnesses the same fees and mileage as are paid in like circumstances in the courts of the United States.
(b) Refusal to obey subpena
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