Washington Revised Code Title 10. Criminal Procedure § 10.58.035. Statement of defendant--Admissibility

(1) In criminal and juvenile offense proceedings where independent proof of the corpus delicti is absent, and the alleged victim of the crime is dead or incompetent to testify, a lawfully obtained and otherwise admissible confession, admission, or other statement of the defendant shall be admissible into evidence if there is substantial independent evidence that would tend to establish the trustworthiness of the confession, admission, or other statement of the defendant.

(2) In determining whether there is substantial independent evidence that the confession, admission, or other statement of the defendant is trustworthy, the court shall consider, but is not limited to:

(3) Where the court finds that the confession, admission, or other statement of the defendant is sufficiently trustworthy to be admitted, the court shall issue a written order setting forth the rationale for admission.

(4) Nothing in this section may be construed to prevent the defendant from arguing to the jury or judge in a bench trial that the statement is not trustworthy or that the evidence is otherwise insufficient to convict.