Mass. Gen. Laws ch. 30A, § 23
(c) Upon the receipt of a complaint by any person, the attorney general shall determine, in a timely manner, whether there has been a violation of the open meeting law. The attorney general may, and before imposing any civil penalty on a public body shall, hold a hearing on any such complaint. Following a determination that a violation has occurred, the attorney general shall determine whether the public body, 1 or more of the members, or both, are responsible and whether the violation was intentional or unintentional. Upon the finding of a violation, the attorney general may issue an order to:
(f) As an alternative to the procedure in subsection (b), the attorney general or 3 or more registered voters may initiate a civil action to enforce the open meeting law.
Any action under this subsection shall be filed in Suffolk superior court with respect to state public bodies and, with respect to all other public bodies, in the superior court in any county in which the public body acts or meets.
In any action filed pursuant to this subsection, in addition to all other remedies available to the superior court, in law or in equity, the court shall have all of the remedies set forth in subsection (c).
In any action filed under this subsection, the order of notice on the complaint shall be returnable not later than 10 days after the filing and the complaint shall be heard and determined on the return day or on such day as the court shall fix, having regard to the speediest possible determination of the cause consistent with the rights of the parties; provided, however, that orders may be issued at any time on or after the filing of the complaint without notice when such order is necessary to fulfill the purposes of the open meeting law. In the hearing of any action under this subsection, the burden shall be on the respondent to show by a preponderance of the evidence that the action complained of in such complaint was in accordance with and authorized by the open meeting law; provided, however, that no civil penalty may be imposed on an individual absent proof that the action complained of violated the open meeting law.