Oregon Revised Statutes Public Financial Administration § 294.710

(1) Any county with a population of less than 500,000 inhabitants, based on the most recently available data published or officially provided by the Portland State University Population Research Center, may establish, with the approval of a majority of its electors voting on the question, a tax supervising and conservation commission that substantially conforms to the provisions of ORS 294.605 to 294.705.

(2) Any county with a population of 500,000 or more inhabitants, based on the most recently available data published or officially provided by the Portland State University Population Research Center, may establish a tax supervising and conservation commission that substantially conforms to the provisions of ORS 294.605 to 294.705 provided the county obtains the approval of a majority of the members of its governing body voting on the question.

(3) Notwithstanding ORS 294.630, a county under this section may establish its own maximum annual appropriation to a tax supervising and conservation commission in the ordinance creating the commission.