Washington Revised Code Title 10. Criminal Procedure § 10.27.140. Witnesses--Attendance

(1) Except as provided in this section, no person has the right to appear as a witness in a grand jury or special inquiry judge proceeding.

(2) A public attorney may call as a witness in a grand jury or special inquiry judge proceeding any person believed by him or her to possess information or knowledge relevant thereto and may issue legal process and subpoena to compel his or her attendance and the production of evidence.

(3) The grand jury or special inquiry judge may cause to be called as a witness any person believed by it to possess relevant information or knowledge. If the grand jury or special inquiry judge desires to hear any such witness who was not called by a public attorney, it may direct a public attorney to issue and serve a subpoena upon such witness and the public attorney must comply with such direction. At any time after service of such subpoena and before the return date thereof, however, the public attorney may apply to the court which impaneled the grand jury for an order vacating or modifying the subpoena on the grounds that such is in the public interest. Upon such application, the court may in its discretion vacate the subpoena, extend its return date, attach reasonable conditions to directions, or make such other qualification thereof as is appropriate.

(4) The proceedings to summon a person and compel him or her to testify or provide evidence shall as far as possible be the same as proceedings to summon witnesses and compel their attendance. Such persons shall receive only those fees paid witnesses in superior court criminal trials.