RCW 2.04.190: Rules of pleading, practice, and procedure generally.

The supreme court shall have the power to prescribe, from time to time, the forms of writs and all other process, the mode and manner of framing and filing proceedings and pleadings; of giving notice and serving writs and process of all kinds; of taking and obtaining evidence; of drawing up, entering and enrolling orders and judgments; and generally to regulate and prescribe by rule the forms for and the kind and character of the entire pleading, practice and procedure to be used in all suits, actions, appeals and proceedings of whatever nature by the supreme court, superior courts, and district courts of the state. In prescribing such rules the supreme court shall have regard to the simplification of the system of pleading, practice and procedure in said courts to promote the speedy determination of litigation on the merits.