RCW 9.95.214

Whenever a defendant convicted of a misdemeanor or gross misdemeanor is placed on probation under RCW 9.92.060 or 9.95.210, and the defendant is supervised by a county probation department, the county probation department may assess and collect from the defendant for the duration of the term of supervision a monthly assessment not to exceed $100 per month. This assessment shall be paid to the agency supervising the defendant and shall be applied, along with funds appropriated by the legislature, toward the payment or part payment of the cost of supervising the defendant. The county probation department shall suspend such assessment while the defendant is being supervised by another state pursuant to RCW 9.94A.745, the interstate compact for adult offender supervision.