The legislature currently establishes a bi-partisan commission for the purpose of redistricting Congressional and state legislative districts. Congressional and legislative redistricting are controlled by Article II, Section 43 of the Washington Constitution and the Washington Redistricting Act, RCWA 44.05. Municipal and county redistricting are controlled by statue. See RCWA 29A.76.010.
The Districting Commission is composed of five members. The legislative leader of the two largest political parties in each house of the legislature appoints one voting member to the commission. The four appointed members select the remaining non-voting member who serves as chairperson. No elected official and no person elected to legislative district, county or state political party office within the last two years, can serve on the commission. See RCWA 44.05.050. If the commission fails to pass a districting plan, the responsibility will fall to the Washington Supreme Court.
In the 2001 cycle, the districting commission was divided, with two Democrats and two Republicans, headed by a nonpartisan, nonvoting chairman. The commission failed to meet the required deadline and the Supreme Court took control and completed both congressional and legislative redistricting.
Read more about Washington's redistricting process.