No official of an agency who renders a decision in a contested case shall consult any person on any issue of fact except upon notice and opportunity for all parties to participate, save to the extent required for the disposition of ex parte matters authorized by law.
HRS § 91-13
Attorney General Opinions
A division chief acting as a hearings officer must comply with this section, and may not consult any person in or outside of the division on any issue of fact, with the exception of ex parte matters authorized by law. Att. Gen. Op. 98-6.
Where director's violation of this section by consulting materials and individuals outside the record did not prejudice appellant's substantial rights, harmless error.87 Haw. 217,953 P.2d 1315.