S.D. Codified Laws § 37-5B-37
For the purpose of any investigation or proceeding under this chapter, the director or any person designated by the director may administer oaths and affirmations, subpoena witnesses and compel their attendance, take evidence and require the production of any books, papers, correspondence, memoranda, agreements, or other documents or records which the director deems relevant or material to the inquiry.
Any order of the director shall be served by mailing a copy thereof by certified mail to the most recent address of the recipient of the order as it appears in the files of the director. Any subpoena shall be served in the same manner as provided in civil actions in circuit court.
No provision of this chapter either creates any privilege or derogates from any privilege which exists at common law or otherwise, if documentary or other evidence is sought under a subpoena directed to the director or any of the director's officers or employees.
If any person refuses to obey a subpoena, the circuit court, upon application by the director, may issue an order directing the person to appear before the director, or the officer designated by the director, to produce documentary evidence if so ordered, or to give evidence on the matter under investigation or in question. Failure to obey the order of the court is punishable by the court as a contempt of court.
SDCL 37-5B-37