Wash. Rev. Code § 29A.72.010
If any legal voter of the state, either individually or on behalf of an organization, desires to petition the legislature to enact a proposed measure, or submit a proposed initiative measure to the people, or order that a referendum of all or part of any act, bill, or law, passed by the legislature be submitted to the people, he or she shall file with the secretary of state:
[ 2015 c 72 s 10; 2003 c 111 s 1802; 1982 c 116 s 1; 1965 c 9 s 29.79.010. Prior: 1913 c 138 s 1, part; RRS s 5397, part. Formerly RCW 29.79.010.]