Wash. Rev. Code § 26.27.491
(1) Unless the court issues a temporary emergency order pursuant to RCW 26.27.231, upon a finding that a petitioner is entitled to immediate physical custody of the child, the court shall order that the petitioner may take immediate physical custody of the child unless the respondent establishes that:
(a) The child custody determination has not been registered and confirmed under RCW 26.27.441 and that:
[ 2001 c 65 s 310.]