N.H. Rev. Stat. § 24:15

I. No county commissioner, or elected or appointed county officer, shall pay, or agree to pay, or incur any liability for the payment of, any sum of money for which the county convention has made no appropriation, or in excess of any appropriation so made except for the payment of judgments rendered against the county. II. In the case of an emergency, the county commissioners, or an elected or appointed county officer, may apply to the executive committee, which, after a public hearing, may grant to the county commissioners or officer authority in writing to make such emergency payment. III. Unless otherwise ordered by the county convention, under RSA 24:14, whenever it appears that the amount appropriated for a specific purpose will not be used in whole or in part for such purpose, the county commissioners may use such sum to augment other appropriations, if necessary, provided the total payments for all purposes do not exceed the total sum of appropriations in any year made by the county convention. IV. If any county commissioner, or elected or appointed county officer, is found in a prosecution for violation of RSA 643:1 to have paid or incurred any liability for the payment of any sum of money contrary to this section, it shall be prima facie evidence that such county commissioner or officer has knowingly refrained from performing a duty imposed by law.