(1) For police departments with fewer than six commissioned officers, including the police chief, the classified civil service and provisions of this chapter includes all full paid employees of the department of the city, town, or municipality.
(2) For police departments with six or more commissioned officers, including the police chief, the legislative body of a city, town, or municipality may exempt from civil service individuals appointed as police chief after July 1, 1987.
(a) If the police chief is not exempt, the classified civil service includes all full paid employees of the department of the city, town, or municipality, including the police chief.
(b) If the police chief is exempt, the classified civil service includes all full paid employees of the department of the city, town, or municipality, except the police chief and an additional number of positions, designated the unclassified service, determined as follows:
(4) All appointments to and promotions in the department shall be made solely on merit, efficiency, and fitness except as provided in RCW 35.13.360 through 35.13.400, which shall be ascertained by open competitive examination and impartial investigation. No person in the unclassified service shall be reinstated in or transferred, suspended, or discharged from any such place, position, or employment contrary to the provisions of this chapter.