(1) Commissioners. The commissioners may preside in any adjudicative proceeding with or without the assistance of an administrative law judge. When the commissioners preside, they are presiding officers as that term is used in chapter 34.05 RCW and in this chapter. When the commissioners preside with the assistance of an administrative law judge, the administrative law judge also is a presiding officer, except for purposes of making final decisions on substantive matters in the proceeding. The administrative law judge may enter procedural and other interlocutory orders. When the commissioners preside, they may enter procedural and other interlocutory orders and will enter one or more final orders in the proceeding to resolve the substantive matters presented.

(2) Administrative law judge. The director of the administrative law division will designate an administrative law judge to preside in individual proceedings, either to assist the commissioners in their role as presiding officers as described in subsection (1) of this section, or to serve alone as the presiding officer. When serving alone as the presiding officer, the administrative law judge will enter one or more initial orders, unless the parties and the commission agree to waive an initial order, or applicable law prohibits entry of an initial order. An initial order becomes final if no party petitions for administrative review within twenty days and the commissioners do not review the order on their own motion. The commissioners will enter a final order if a party petitions for, or the commission on its own motion undertakes, administrative review of an initial order, if the parties and the commission agree to waive an initial order, or as otherwise provided by law.