Mass. Gen. Laws ch. 12 § 25A
Money to be used for necessary expenses to be incurred in the performance of the duties of a district attorney in relation to any investigation or proceeding in any county in his district, to an amount not exceeding twenty-four thousand dollars in any one year, shall be advanced to him by the treasurer of the commonwealth, or placed to his credit for advance under his direction to persons designated by him, upon the presentation of a certificate signed by him certifying that such amount is necessary for use as aforesaid. Every sum so advanced shall be accounted for by the said district attorney within two months after such advance and said accounts shall be approved in the manner provided in section twenty-four for approving bills incurred by district attorneys; provided, that all sums so advanced by the treasurer during any financial year shall be accounted for, and any unexpended balances thereof be repaid to said treasurer, prior to January tenth next following the close of said financial year.
Mass. Gen. Laws ch. 12, § 25A