Massachusetts General Laws Part I. Administration of the Government (Ch. 1-182) Ch. 140, § 81

Said book shall at all reasonable times be open to the inspection of the mayor, of the members of the board of police, of the superintendent of police and deputy superintendents, of the chief inspector of police, of any officer of the state police or of any person authorized by them in writing for that purpose who exhibits such written authority to such pawnbroker.