Hawaii Revised Statutes Division 3. Property; Family § 560:5-308

(a) Unless excused by the court for good cause, the proposed guardian shall attend the hearing. The respondent shall attend and participate in the hearing, unless excused by the court for good cause. The respondent may present evidence and subpoena witnesses and documents, examine witnesses, including any court-appointed physician, psychologist, or other individual qualified to evaluate the alleged impairment, and the kokua kanawai, and otherwise participate in the hearing. The hearing may be held in a location convenient to the respondent and may be closed upon the request of the respondent and a showing of good cause.

(b) Any person may request permission to participate in the proceeding. The court may grant the request, with or without hearing, upon determining that the best interest of the respondent will be served. The court may attach appropriate conditions to the participation.