For the purposes of conducting any hearing under this section, the Secretary may issue subpoenas for the attendance and testimony of witnesses and the production of relevant papers, books, and documents, and may administer oaths. Witnesses summoned shall be paid the same fees and mileage that are paid to witnesses in the courts of the United States. In case of contempt or refusal to obey a subpoena served upon any person pursuant to this subsection, the district court of the United States for any district in which such person is found, resides, or transacts business, upon application by the United States 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, or both, and any failure to obey such order of the court may be punished by such court as a contempt thereof.
Any person against whom a civil penalty is assessed under subsection (a) or against whose vessel a permit sanction is imposed under subsection (b) (other than a permit suspension for nonpayment of penalty or fine) may obtain review thereof in the United States district court for the appropriate district by filing a complaint against the Secretary in such court within 30 days from the date of such penalty or sanction. The Secretary shall promptly file in such court a certified copy of the record upon which such penalty or sanction was imposed, as provided in section 2112 of title 28. The findings and order of the Secretary shall be set aside by such court if they are not found to be supported by substantial evidence, as provided in section 706(2) of title 5.