Wash. Rev. Code § 41.80.080
(1) The commission shall determine all questions pertaining to representation and shall administer all elections and cross-check procedures, and be responsible for the processing and adjudication of all disputes that arise as a consequence of elections and cross-check procedures. The commission shall adopt rules that provide for at least the following:
(2)
(4) No question concerning representation may be raised if:
[ 2019 c 230 s 17; 2002 c 354 s 309.]