A check differs from a warrant in that a check is a direct draft drawn upon a bank (holding county funds) and is payable upon demand whereas a warrant is an order to the county trustee to pay to the payee monies from the county treasury if and when money is available.  As a result of legislation enacted in 1992, county trustees have authority to switch from the traditional warrant system to a checking system for disbursing county funds.  T.C.A. § 5-8-210.  The trustee may adopt the checking system by giving at least thirty days’ notice to each official authorized to sign checks.  Under this system the county trustee must certify that funds are available to pay checks before they are released, thereby preventing department heads from issuing disbursement warrants when cash is unavailable in the account.  Anyone who signs or issues a check without the required certification is subject to removal from office and personal liability for any improperly disbursed funds.  T.C.A. § 5-8-210(k).