Hawaii Revised Statutes Division 2. Business § 412:2-111

In the course of an investigation of matters affecting the interest of consumers or depositors or of any other matter within the jurisdiction of the division, the commissioner may summon persons and subpoena witnesses, compel their attendance, administer oaths and examine any person under oath, and require the production of books, papers, documents, or objects that the commissioner deems relevant or material to the inquiry. Any summons or subpoena may be served by certified mail with return receipt requested. Powers granted under this section may be enforced by the circuit court.