Wash. Rev. Code ch. 64.28
Joint tenancies.
64.28.010Joint tenancies with right of survivorship authorized—Methods of creation—Creditors' rights saved.64.28.020Interest in favor of two or more is interest in common—Exceptions for joint tenancies, partnerships, trustees, etc.—Presumption of community property.64.28.030Bank deposits, choses in action, community property agreements not affected.64.28.040Character of joint tenancy interests held by both spouses or both domestic partners.