Mass. Gen. Laws ch. 22C § 37
Not less than seven days before the time set for the release or discharge on parole, or otherwise, of any person confined in a penal or reformatory institution of the commonwealth or of any county under sentence for an assault of an indecent nature under section thirteen A of chapter two hundred and sixty-five, for a violation of any provision of sections thirteen B, 13B1/2, 13B 3/4 or twenty-two to twenty-four, inclusive, of said chapter two hundred and sixty-five, of sections sixteen, seventeen, thirty-four or thirty-five of chapter two hundred and seventy-two, and so much of section fifty-three of said chapter two hundred and seventy-two as pertains to lewd, wanton and lascivious persons in speech or behavior or to persons guilty of indecent exposure, or of any person confined in any facility, as defined in section one of chapter one hundred and twenty-three, or in the Bridgewater state hospital, who was removed thereto after conviction of a violation of any such provision or was committed thereto during the pendency of a complaint or indictment for a violation of any such provision, the officer in charge of such institution, department or hospital, as the case may be, shall notify the colonel in writing of such intended release or discharge; provided, that if any person is released or discharged as aforesaid under such circumstances that it is not possible for the officer in charge to comply with the foregoing provision, he shall so notify the colonel as soon as possible that such person will be or has been released or discharged as aforesaid. Upon receipt of any such notice, the colonel shall furnish to the police authorities of each city and town, and to each district attorney within the commonwealth the name of the person referred to in such notice, his known aliases, if any, his last known address, his age, height and weight, his photograph, a description of his fingerprints, a summary of his criminal history and a list of any institutions for the insane and departments for defective delinquents in which he has been known to have been confined, and such other information as the colonel deems necessary.
In all cases covered by this section where a fine is imposed or sentence suspended, the clerk of court shall furnish release data to the colonel of state police on forms furnished by him.
In all cases where a person has been found guilty of any offense of similar nature to those enumerated above in any court of competent jurisdiction outside of the commonwealth and the colonel has knowledge that such person has been released or resides within the commonwealth, the aforesaid descriptive data insofar as available may be furnished to the police authorities of each city and town and to each district attorney, within the commonwealth.
Mass. Gen. Laws ch. 22C, § 37