Wash. Rev. Code § 10.31.060
Whenever any person or persons shall have been indicted or accused on oath of any public offense, or thereof convicted, and a warrant of arrest shall have been issued, the magistrate issuing such warrant, or any justice of the supreme court, or any judge of either the court of appeals or superior court may indorse thereon an order signed by him or her and authorizing the service thereof by telegraph or teletype, and thereupon such warrant and order may be sent by telegraph or teletype to any marshal, sheriff, constable or police officer, and on the receipt of the telegraphic or teletype copy thereof by any such officer, he or she shall have the same authority and be under the same obligations to arrest, take into custody and detain the said person or persons, as if the said original warrant of arrest, with the proper direction for the service thereof, duly indorsed thereon, had been placed in his or her hands, and the said telegraphic or teletype copy shall be entitled to full faith and credit, and have the same force and effect in all courts and places as the original; but prior to indictment and conviction, no such order shall be made by any officer, unless in his or her judgment there is probable cause to believe the said accused person or persons guilty of the offense charged: PROVIDED, That the making of such order by any officer aforesaid, shall be prima facie evidence of the regularity thereof, and of all the proceedings prior thereto. The original warrant and order, or a copy thereof, certified by the officer making the order, shall be preserved in the telegraph office or police agency from which the same is sent, and in telegraphing or teletyping the same, the original or the said certified copy may be used.
RCW 10.31.060