RCW 11.96A.125: Mistake of fact or law in terms of will or trust—Judicial and nonjudicial reform.

The terms of a will or trust, even if unambiguous, may be reformed by judicial proceedings under this chapter to conform the terms to the intention of the testator or trustor if it is proved by clear, cogent, and convincing evidence that both the intent of the testator or trustor and the terms of the will or trust were affected by a mistake of fact or law, whether in expression or inducement. This does not limit the ability to reform the will or trust using the binding nonjudicial procedures of RCW 11.96A.220.