Mass. Gen. Laws ch. 66, § 13: Custodian to demand records; compelling compliance

Section 13. Whoever is entitled to the custody of public records shall demand the same from any person unlawfully having possession of them, who shall forthwith deliver the same to him. Upon complaint of any public officer entitled to the custody of a public record, the superior court shall have jurisdiction in equity to compel any person unlawfully having such record in his possession to deliver the same to the complainant.