Spousal Privileges
There are two kinds of spousal privilege (which also applies to domestic partners) in Washington State. Under the first, if one spouse is a party to an action, the other spouse cannot be examined without the consent of the first spouse, even if the testimony sought has nothing to do with confidential spousal communications. This means the other spouse cannot be a witness at all unless the first spouse agrees to it. It applies only why the couple is still married.
The second is more like the familiar attorney-client privilege: a spouse may not be examined as to any confidential communication made to the other spouse while they were married, even if they are no longer married at the time the privilege is invoked. The privilege can be waived by the other spouse.
There are some common-sense exceptions which apply to both kinds of privilege. They do not apply in a civil suit brought by one spouse against the other spouse. They do not apply to criminal litigation where one spouse is alleged to have committed a crime against the other. They do not apply to criminal actions if the couple got married after formal charges were filed. They do not apply to a criminal action where one spouse is alleged to have committed a crime against the other spouse’s child or ward. Finally, they do not apply to certain actions to have one spouse involuntarily civilly committed, but the other spouse may not be compelled to testify in such an action.
There is also a workaround of sorts: if a spouse has made statements outside of court, there is nothing to stop a non-spouse from testifying that the spouse made those statements. Nor can extrajudicial documents be excluded (unless they constitute confidential interspousal communications and no exceptions apply).