Oregon Revised Statutes Counties and County Officers § 210.180

Any law or rule providing for the payment of any demand of any kind or nature, except the salary of the county accountant, out of the treasury or any fund thereof, whether from public funds or private funds deposited therein, shall be construed as requiring auditing and approval by the accountant, and an order of the board of county commissioners before payment. No order or warrant for the payment of any demand shall be valid, either in the hands of the original payee or holder, or any transferee or assignee thereof, unless the demand for which the same was issued shall have been first duly audited and approved by the accountant.