Washington Revised Code Title 11. Probate and Trust Law § 11.108.070. Presumptions for the interpretation, construction, and administration of governing instrument

(1) The legislature finds that the citizens and residents of the state, and nonresidents of the state having property located in Washington, desire to take full advantage of the exemptions, exclusions, deductions, and credits allowable under the federal estate, gift, income, and generation-skipping transfer taxes, and the Washington counterparts to those taxes, if any, unless the facts and circumstances indicate otherwise, or the transferor has expressed a contrary intent in the governing instrument.

(2) In interpreting, construing, or administering a governing instrument, absent a clear expression of intent by the transferor to the contrary, the following presumptions apply and may only be rebutted by clear, cogent, and convincing evidence to the contrary, but these presumptions of intent do not require the making of any particular voluntary tax election:

(3) References in this chapter to provisions of the Internal Revenue Code include references to similar provisions, if any, of applicable state law.