Oregon Revised Statutes Public Financial Administration § 292.250

(1) A person may not be reimbursed by a state agency for the use on official or state related business of a privately owned motor vehicle at a rate to exceed the rates established and regulated by the Oregon Department of Administrative Services. Reimbursement shall be paid only for distances actually traveled and trips made in the performance of official or state related duties.

(2) The department shall adopt a statewide policy for implementation of a tiered mileage reimbursement rate schedule for reimbursement by state agencies for the use of a privately owned motor vehicle while conducting state business.

(3) The reimbursement rates adopted by the department must be equivalent to the reimbursement rates established by the United States General Services Administration for reimbursement for the use of privately owned motor vehicles when conducting government business.

(4) The rates adopted under subsection (2) of this section shall be deemed to be in full compensation for all and every expense, charge or liability incurred through the use of the privately owned motor vehicle, including the cost of gasoline, oil, repair parts, depreciation, taxes, insurance and maintenance and upkeep of every kind and nature.

(5) No law enacted before August 2, 1951, allowing the recovery by any person of necessary and reasonable traveling expenses incurred in the performance of official duties shall be construed to authorize payment by the state for the use of a privately owned motor vehicle on a basis in excess of the rate provided in subsection (1) of this section.