(a) An agency shall initiate a contested case proceeding when one is required by law. Unless otherwise provided by law, an agency shall decide a contested case only in accordance with the contested case procedures of the Administrative Procedure Act. Upon initiation of a contested case proceeding, an agency may, by order, provide that the report or order of the administrative law judge constitutes the final decision in the case.

(b) As an alternative to initiating or continuing with a contested case proceeding, the parties, subsequent to agency approval, may enter into a written agreement to submit the issues raised to arbitration by an administrative law judge according to sections 572B.01 to 572B.31.