Mass. Gen. Laws ch. 53, § 43: Polls; hours when open

Section 43. The polls at every primary shall be open at least thirteen hours. Such hours shall be designated in cities by the aldermen or councillors, and in towns by by-laws or vote, or, in default of such by-laws or vote, by the selectmen. The polls shall in no case be kept open after eight o'clock in the evening. The polls shall not be closed before eight o'clock in the evening.