Wash. Rev. Code § 6.27.270
If it appears from the garnishee's answer or otherwise that the garnishee had possession or control, when the writ was served, of any personal property or effects of the defendant liable to execution, and if the required return or affidavit showing service on or mailing to the defendant is on file, the court shall render a decree requiring the garnishee to deliver up to the sheriff on demand, and after making arrangements with the sheriff as to time and place of delivery, such personal property or effects or so much of them as may be necessary to satisfy the plaintiff's claim. If a judgment has been rendered in favor of the plaintiff against the defendant, such personal property or effects may be sold in the same manner as any other property is sold upon an execution issued on said judgment. If judgment has not been rendered in the principal action, the sheriff shall retain possession of the personal property or effects until the rendition of judgment therein, and, if judgment is thereafter rendered in favor of the plaintiff, said personal property or effects, or sufficient of them to satisfy such judgment, may be sold in the same manner as other property is sold on execution, by virtue of an execution issued on the judgment in the principal action. If judgment is rendered in the action against the plaintiff and in favor of the defendant, such effects and personal property shall be returned to the defendant by the sheriff: PROVIDED, HOWEVER, That if such effects or personal property are of a perishable nature, or the interests of the parties will be subserved by making a sale thereof before judgment, the court may order a sale thereof by the sheriff in the same manner as sales upon execution are made, and the proceeds of such sale shall be paid to the clerk of the court that issued the writ, and the same disposition shall be made of the proceeds at the termination of the action as would have been made of the personal property or effects under the provisions of this section in case the sale had not been made.
RCW 6.27.270
Severability-1988 c 231: See note following RCW 6.01.050.