For the purposes of this chapter, the Secretary shall at all reasonable times have access to, for the purpose of examination, and the right to copy any documentary evidence of any person with respect to whom such authority is exercised; and the Secretary shall have power to require by subpena the attendance and testimony of witnesses and the production of all such documentary evidence relating to any matter under investigation by the Secretary, and may administer oaths and affirmations, examine witnesses, and receive evidence.
Such attendance of witnesses, and the production of such documentary evidence, may be required from any place in the United States, at any designated place of hearing. In case of disobedience to a subpena the Secretary may invoke the aid of any court designated in subsection (h) of this section in requiring the attendance and testimony of witnesses and the production of documentary evidence.
Any such court within the jurisdiction of which such inquiry is carried on may, in case of contumacy or refusal to obey a subpena issued to any person, issue an order requiring such person to appear before the Secretary or to produce documentary evidence if so ordered, or to give evidence touching the matter in question; and any failure to obey such order of the court may be punished by such court as a contempt thereof.
Witnesses summoned before the Secretary shall be paid the same fees and mileage that are paid witnesses in the courts of the United States, and witnesses from whom depositions are taken and the persons taking the same shall severally be entitled to the same fees as are paid for like services in the courts of the United States.
Any person who shall neglect or refuse to attend and testify, or to answer any lawful inquiry, or to produce documentary evidence, if in the power of the person to do so, in obedience to the subpena or lawful requirement of the Secretary, shall be guilty of a misdemeanor, and upon conviction thereof be subject to imprisonment for not more than 1 year or a fine of not more than $10,000 or both the imprisonment and fine.