Wash. Rev. Code § 46.70.111
For the purpose of any investigation or proceeding under this chapter, the director or any officer designated by him or her may administer oaths and affirmations, subpoena witnesses, 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.
[ 2010 c 8 s 9084; 1967 ex.s. c 74 s 15.]