Mo. Rev. Stat. § 109.280: Agency heads may determine nature and form of records — confidential records to be so treated.

Nothing in sections 109.200 to 109.310 shall be construed to divest agency heads of the authority to determine the nature and form of the records required in the administration of their several departments, or to compel the removal of records deemed necessary by them in the performance of their statutory duties. Any records made confidential by law shall be so treated in the state or local records center and archives.