Section 823.031 - Investigating complaints against carriers(1) The Department of Transportation may investigate any complaint filed against a person whose business or activities are regulated by one or more of the statutes regarding motor carriers or railroads, jurisdiction for the enforcement or regulation of which is conferred upon the department.(2) Any hearing held as a result of a complaint or investigation under subsection (1) of this section shall be a contested case hearing, in the manner provided in ORS 183.413 to 183.497.