Iowa Code § 331.476: Expenditures confined to receipts.

Except as otherwise provided in section 331.478, a county officer or employee shall not allow a claim, issue a warrant, or execute a contract which will result during a fiscal year in an expenditure from a county fund in excess of an amount equal to the collectible revenues in the fund for that fiscal year plus any unexpended balance in the fund from a previous year. A county officer or employee allowing a claim, issuing a warrant, or executing a contract in violation of this section is personally liable for the payment of the claim or warrant or the performance of the contract.