Mass. Gen. Laws ch. 37, § 21A: Travel vouchers or other verification of travel expenses

Section 21A. For the purposes of paying the salary and travel expenses of a sheriff pursuant to sections 17 and 21, the commonwealth shall pay said salary and travel expenses whenever the sheriff is an employee of the commonwealth; provided, that said travel expenses shall be reimbursed only upon the submission of travel vouchers or other verification of travel expenses to the comptroller.