Massachusetts General Laws Part I. Administration of the Government (Ch. 1-182) Ch. 149, § 41

Except as provided in section sixty-five of chapter ninety-two, all laborers, workmen and mechanics employed by the commonwealth in any capacity, or by any officer, department or board on behalf of the commonwealth, who are permanent employees or who have been certified under the civil service laws, and whose services can be dispensed with, shall be given a half holiday on every Saturday in the year without loss of pay.