No employer may discharge, threaten to discharge, demote, deny a promotion to, sanction, discipline, retaliate against, harass, or otherwise discriminate against an employee with respect to compensation, terms, conditions, or privileges of employment because the employee:

(1) Exercised rights under RCW 49.76.030 or 49.76.115;

(2) Filed or communicated to the employer an intent to file a complaint under RCW 49.76.070 or 49.76.100; or

(3) Participated or assisted, as a witness or otherwise, in another employee's attempt to exercise rights under RCW 49.76.030, 49.76.115, 49.76.070, or 49.76.100.