ORS § 20.140
When the state or any county, city or school district in this state, or an officer, employee or agent thereof appearing in a representative or other official capacity, is a party in an action or proceeding in any court in this state, that party is not required to pay in advance to a state or county officer any fee taxable as costs and disbursements in the action or proceeding. If that party is entitled to recover costs and disbursements in the action or proceeding, the amount of the fee not paid in advance shall be included in the statement of costs and disbursements claimed by the party, shall be entered as part of the judgment and, if recovered by the party, shall be paid by the party to the state or county officer entitled to receive the fee. The party shall employ reasonable effort to recover the amount of the fee.
ORS 20.140