All officers and employees of each county shall aid in all proper ways in carrying out the provisions of this chapter, and such rules and regulations as may, from time to time, be prescribed by the commission and afford the commission, its members, and employees, all reasonable facilities and assistance in the inspection of books, papers, documents, and accounts applying or in any way appertaining to any and all offices, places, positions, and employments, subject to civil service, and also shall produce such books, papers, documents, and accounts, and attend and testify, whenever required so to do by the commission or any commissioner.
RCW 41.14.200