Wash. Rev. Code § 71.34.910
For purposes of this chapter, at any hearing the petitioner, the respondent, the witnesses, the interpreters, and the presiding judicial officer may be present and participate either in person or by video, as determined by the court. The term "video" as used in this section includes any functional equivalent. At any hearing conducted by video, the technology used must permit the judicial officer, counsel, all parties, and the witnesses to be able to see, hear, and speak, when authorized, during the hearing; to allow attorneys to use exhibits or other materials during the hearing; and to allow the respondent's counsel to be in the same location as the respondent unless otherwise requested by the respondent or the respondent's counsel. Witnesses in a proceeding may also appear in court through other means, including telephonically, pursuant to the requirements of superior court civil rule 43. Notwithstanding the foregoing, the court, upon its own motion or upon a motion for good cause by any party, may require all parties and witnesses to participate in the hearing in person rather than by video. In ruling on any such motion, the court may allow in-person or video testimony; and the court may consider, among other things, whether the respondent's alleged behavioral health disorder affects the respondent's ability to perceive or participate in the proceeding by video.
RCW 71.34.910