Wash. Rev. Code § 9.44.080
Misconduct in signing a petition
In a situation not covered by RCW 29A.84.220, 29A.84.230, 29A.84.240, or 29A.84.250, every person who shall willfully sign the name of another person or of a fictitious person, or for any consideration, gratuity or reward shall sign his or her own name to or withdraw his or her name from any referendum or other petitio…