Wash. Rev. Code § 35.63.030
The ordinance, resolution, or act creating the commission shall set forth the number of members to be appointed, not more than one-third of which number may be ex officio members by virtue of office held in any municipality. The term of office for ex officio members shall correspond to their respective tenures. The term of office for the first appointive members appointed to such commission shall be designated from one to six years in such manner as to provide that the fewest possible terms will expire in any one year. Thereafter the term of office for each appointive member shall be either four or six years, as determined by legislative action of the council.
Vacancies occurring otherwise than through the expiration of terms shall be filled for the unexpired term. Members may be removed, after public hearing, by the appointing official, with the approval of his or her council or board, for inefficiency, neglect of duty, or malfeasance in office.
The members shall be selected without respect to political affiliations and they shall serve without compensation.
RCW 35.63.030