(1) The adjudicative proceeding shall be conducted as provided in RCW 34.05.449 through 34.05.455.

(2) The presiding officer may take the following actions to the extent not already determined in a prehearing order:

(a) Conduct the hearing de novo;

(b) Determine the order of presentation of evidence;

(c) Administer oaths and affirmations;

(d) Issue subpoenas;

(e) Rule on procedural matters, objections, motions, and offers of proof;

(f) Receive relevant evidence;

(g) Interrogate witnesses called by the parties in an impartial manner to develop any facts necessary to fairly and adequately decide the matter;

(h) Call additional witnesses and request additional exhibits deemed necessary to complete the record and receive such evidence subject to full opportunity for cross-examination and rebuttal by all parties;

(i) Take any appropriate action necessary to maintain order during the adjudicative proceeding;

(j) Determine whether to permit or require oral argument or briefs and determine the time limits for submission thereof;

(k) Permit photographic and recording equipment at hearing subject to conditions necessary to preserve confidentiality and prevent disruption;

(l) Permit a person to waive any right conferred upon that person by chapter 34.05 RCW or this chapter, except as precluded by law; and

(m) Take any other action necessary and authorized by applicable law or rule.

(3) The presiding officer shall:

(a) Apply as the first source of law governing an issue those statutes and rules deemed applicable to the issue;

(b) If there is no statute or rule governing the issue, resolve the issue on the basis of the best legal authority and reasoning available, including that found in federal and Washington constitutions, statutes, rules, and court decisions; and

(c) Not declare any statute or rule invalid.

(4) If the validity of any statute or rule is raised as an issue, the presiding officer may permit arguments to be made on the record concerning the issue for the purpose of subsequent review.

(5) A party may move to disqualify the presiding officer pursuant to RCW 34.05.425(3).