Washington Revised Code Title 48. Insurance § 48.18.070. Alteration of application

(1) Any application for insurance in writing by the applicant shall be altered solely by the applicant or by his or her written consent, except that insertions may be made by the insurer for administrative purposes only in such manner as to indicate clearly that such insertions are not to be ascribed to the applicant.  Violation of this provision shall be a misdemeanor.

(2) Any insurer issuing an insurance contract upon such an application unlawfully altered by its officer, employee, or agent shall not have available in any action arising out of such contract, any defense which is based upon the fact of such alteration, or as to any item in the application which was so altered.