(a)    The Secretary, at all reasonable times, shall have access to any documentary evidence of any person being investigated or proceeded against and shall have the right to copy it for examination purposes. The Secretary may require, by subpoena, the attendance and testimony of any witness and the production of any documentary evidence of any person relating to any matter under investigation. The Secretary may sign subpoenas, may administer oaths and affirmations, examine witnesses, and receive evidence.

(b)    Attendance of any witness and the production of documentary evidence may be required at any designated place of hearing. In case of disobedience to a subpoena, the Secretary may invoke the aid of any court designated in § 4–225 of this subtitle, to require the attendance and testimony of any witness and the production of documentary evidence.

(c)    The Secretary may order testimony to be taken by deposition, in any proceeding or investigation pending under this subtitle, at any stage of the proceeding or investigation. Any person designated by the Secretary and possessing the authority to administer oaths may take a deposition. The testimony shall be reduced to writing by the person taking the deposition, or under his direction, and shall be subscribed by the deponent. Any person may be compelled to appear, depose, and produce documentary evidence in the same manner as witnesses may be compelled to appear, testify, and produce documentary evidence before the Secretary.

(d)    No person may be excused from attending and testifying or from producing any book, paper, schedule or charges, contract, agreement, or other documentary evidence before the Secretary or in obedience to the subpoena of the Secretary, or in any cause or proceeding, criminal or otherwise, based upon or growing out of any alleged violation of this subtitle, on the ground that the testimony or evidence required of him may tend to incriminate him or subject him to a penalty or forfeiture. After claiming a privilege against self–incrimination, no individual may be prosecuted or subjected to any penalty or forfeiture for any matter which he is compelled to testify or produce evidence in obedience to a subpoena, except prosecution and punishment for perjury committed in testifying.

(e)    Any person taking a deposition in accordance with this subtitle shall be entitled to the same fees paid for similar services in State courts.