Mass. Gen. Laws ch. 38 § 7
If, during the course of investigation, the medical examiner is of the opinion that the death may have been caused by the act or negligence of another, he shall at once notify the district attorney within whose district the deceased was found or, if such act or negligence has occurred in a different district, the district attorney for such other district. He shall also make available to the district attorney any and all records pertaining to such investigation. He shall in all cases forthwith certify to the city or town clerk or registrar in the place where the deceased died, the name and address, if known, or otherwise a description as full as may be of the deceased, and the cause and manner of death. Notwithstanding any other provision of law, such certification may indicate that the death was caused by auto-immune deficiency syndrome, so-called.
In cases of homicide, after indictment and arraignment, and while the defendant is in custody or subject to the jurisdiction of the court, upon his request, a copy of the official autopsy report and a copy of the inquest report, if any, shall be made available to him by the district attorney in accordance with the provisions of the Massachusetts Rules of Criminal Procedure.
Mass. Gen. Laws ch. 38, § 7