The Chief of Police is hereby authorized to requisition funds in advance of expenditure for the purchase of evidence against the illegal sale of liquor, gambling or other violations of laws.  Each advancement shall be on a memorandum requisition approved by the Commissioner In Charge of the Bureau of Police and charged to the appropriation of the Bureau of Police for evidence procurement.  The requisition shall be accompanied by an affidavit signed by the Chief of Police which shall state that the amount of cash to be advanced will be used only for the purpose of evidence against the illegal sale of liquor, gambling or other violations of laws.  There shall be no further formal accountability for such funds beyond the affidavit.  However, the Chief of Police shall maintain sufficient confidential records to be able to provide a confidential accounting to the Commissioner In Charge on his request.