Hawaii Revised Statutes Division 1. Government § 271G-23

(a) All hearings, investigations, and proceedings shall be governed by chapter 91 and by rules of practice and procedure adopted by the public utilities commission, and in the conduct thereof, the technical rules of evidence need not be applied; provided that in all evidentiary hearings conducted pursuant to chapter 91 in which a carrier has the burden of justifying the reasonableness of its rates, fares, charges, or classifications, the burden of proof of the carrier in proving the reasonableness of expenditures, contracts, leases, or other transactions between the carrier and corporate affiliates of the carrier shall be satisfied only if the reliable, probative and substantial evidence is clear and convincing. No informality in any hearing, investigation, or proceeding, or in the manner of taking testimony shall invalidate any order, decision or rule made, approved, or confirmed by the commission.

(b) Complaints may be made, in writing, by the commission on its own motion or by any person or body politic setting forth any act or thing done, or omitted to be done by any water carrier, including any rule, regulation, rate, or charge, heretofore established or fixed by or for any water carrier, in violation or claimed to be in violation, of any law or of any order or rule of the commission.