Mass. Gen. Laws ch. 140, § 73

The chief of police of a city, the selectmen of a town, any officer authorized by either of them, or a state police officer may at any time enter upon any premises used by a licensed pawnbroker for the purposes of his business, ascertain how he conducts his business, and examine all articles taken in pawn or kept or stored in or upon said premises and all books and inventories relating thereto. Every such pawnbroker, his clerk, agent, servant or other person in charge of the premises shall exhibit to such officer on demand any or all of such articles, books and inventories.