Chapter 81.104.110 Revised Code of Washington (RCW) Independent System Plan Oversight
"The legislature recognizes that the planning processes described in RCW 81.104.100 provide a recognized framework for guiding high capacity transportation studies. However, the process cannot guarantee appropriate decisions unless key study assumptions are reasonable.
To assure appropriate system plan assumptions and to provide for review of system plan results, an expert review panel shall be appointed to provide independent technical review for development of any system plan which is to be funded in whole or in part by the impositions of any voter-approved local option funding sources enumerated in RCW 81.104.140.
(1) The expert review panel shall consist of five to ten members who are recognized experts in relevant fields, such as transit operations, planning, emerging transportation technologies, engineering, finance, law, the environment, geography, economics, and political science.
(2) The expert review panel shall be selected cooperatively by the chair of the legislative transportation committee, the secretary of the department of transportation, and the governor to assure a balance of disciplines. In the case of counties adjoining another state or Canadian province the expert review panel membership shall be selected cooperatively with representatives of the adjoining state or Canadian province.
(3) The chair of the expert review panel shall be designated by the appointing authorities.
(4) The expert review panel shall serve without compensation but shall be reimbursed for expenses according to chapter 43.03 RCW.
(5) The panel shall carry out the duties set forth in subsections (6) and (7) of this section until the date on which an election is held to consider the high capacity transportation system and financing plans. Funds appropriated for expenses of the expert review panel shall be administered by the department of transportation.
(6) The expert panel shall review all reports required in RCW 81.104.100 (2) and shall concentrate on service modes and concepts, costs, patronage and financing evaluations.
(7) The expert panel shall provide timely reviews and comments on individual reports and study conclusions to the department of transportation, the regional transportation planning organization, the joint regional policy committee, and the submitting lead transit agency. In the case of counties adjoining another state or Canadian province, the expert review panel shall provide its reviews, comments, and conclusions to the representatives of the adjoining state or Canadian province.
(8) The legislative transportation committee shall contract for consulting services for expert review panels. The amount of consultant support shall be negotiated with each expert review panel by the legislative transportation committee and shall be paid from appropriations for that purpose from the high capacity transportation account."
Here is a link to the full text of Chapter 81.