Washington Revised Code Title 11. Probate and Trust Law § 11.86.051. When disclaimer barred--Exception

(1) A beneficiary may not disclaim an interest if:

(2) Notwithstanding the provisions of subsection (1)(a) through (c) of this section, a beneficiary's receipt of a benefit from property shall not necessarily bar such beneficiary's disclaimer of an interest in the same property when, prior to the date of the transfer of the interest to be disclaimed, the beneficiary already owned an interest in such property in joint tenancy, as community property, or otherwise. Any such receipt, in the absence of clear and convincing evidence to the contrary, shall be presumed to be an enjoyment or use of the interest the beneficiary already owned, and only after such interest and any benefit from such interest have been exhausted, shall the beneficiary be deemed to have received or accepted any part of the interest to be disclaimed.