Mass. Gen. Laws ch. 43 § 114
As soon as the polls have closed, the election officials at each polling place shall seal the ballot box without opening it, and in such manner that ballots cannot be removed therefrom or inserted therein without breaking the seal, and shall deliver such ballot box at once, as the city clerk may direct, to the central counting place, together with the voting lists, a record of the ballot box register, a record of the number of ballots given out, the ballots spoiled and returned, and the ballots not given out, all of which shall be enclosed in an envelope, and the election officials shall certify thereon as to the identity of the contents thereof. At the central counting place the ballot boxes shall be opened and the number of ballots found therein recorded and compared with the records sent from the polling places. Any discrepancies discovered shall be recorded and dealt with according to the principles laid down by the general election laws, so far as such principles may be applicable. The ballots for the city council shall be counted first and the ballots for the school committee shall be counted second. Ballots cast for other purposes than the election of members to elective bodies shall be counted at the central counting place in accordance with the laws otherwise applicable to the counting thereof. No information regarding the state of the balloting shall be disclosed before the close of the polls.
Mass. Gen. Laws ch. 43, § 114