Oregon Revised Statutes Public Financial Administration § 292.150

(1) The State Treasurer is authorized, under such rules as the treasurer shall promulgate, to make cash advances in payment of mileage allowances of members of the Legislative Assembly, and in payment of earned wages and salaries of clerks and employees thereof, and of state employees during sessions of the Legislative Assembly and in emergency cases, pursuant to assignments executed by payees in favor of the State Treasurer.

(2) Wages and salaries of clerks and employees of the Legislative Assembly shall be so advanced only pursuant to certificates, showing the amount of salary earned and unpaid, signed by the chief clerk of the branch of the Legislative Assembly with which the party receiving the advance is identified and by the Oregon Department of Administrative Services or its duly authorized representative.

(3) The amounts of earned wages and salaries of state employees shall be so advanced only if payable solely from appropriations made by the Legislative Assembly, and then only upon vouchers approved by the proper state officer, board or commission, as the case may be.