Wash. Rev. Code § 35A.13.030
Biennially at the first meeting of the new council the members thereof shall choose a chair from among their number unless the chair is elected pursuant to RCW 35A.13.033. The chair of the council shall have the title of mayor and shall preside at meetings of the council. In addition to the powers conferred upon him or her as mayor, he or she shall continue to have all the rights, privileges, and immunities of a member of the council. The mayor shall be recognized as the head of the city for ceremonial purposes and by the governor for purposes of military law. He or she shall have no regular administrative duties, but in time of public danger or emergency, if so authorized by ordinance, shall take command of the police, maintain law, and enforce order.
RCW 35A.13.030