Attorneys and investigators appointed by the attorney general, and on his payroll, when authorized by the attorney general or his designee, may expend such sums as the attorney general or his designee deems necessary for the purchase of items for evidence, the advancement of fees in cases before United States courts or other State courts, and in the payment of witness or subpoena fees.
     Funds for making expenditures authorized in this Section shall be advanced from funds appropriated or made available by law for the support or use of the office of attorney general or vouchers therefor signed by the attorney general or his designee. Sums so advanced may be paid to the attorney or investigator authorized to receive the advancement, or may be made payable to the ultimate recipient. Any expenditures under this Section shall be audited by the auditor general as part of any mandated audit conducted in compliance with Section 3-2 of the Illinois State Auditing Act.