Wash. Rev. Code § 20.01.310
The director or his or her authorized agents are empowered to administer oaths of verification on said complaints. He or she shall have full authority to administer oaths and take testimony thereunder, to issue subpoenas in the manner prescribed in RCW 20.01.170 requiring attendance of witnesses before him or her, together with all books, memoranda, papers, and other documents, articles, or instruments; to compel the disclosure by such witnesses of all facts known to them relative to the matters under investigation, and all parties disobeying the orders or subpoenas of said director shall be guilty of contempt and shall be certified to the superior court of the state for punishment for such contempt. Copies of records, audits and reports of audits, inspection certificates, certified reports, findings, and all papers on file in the office of the director shall be prima facie evidence of the matters therein contained, and may be admitted into evidence in any hearing provided in this chapter.
RCW 20.01.310