Mass. Gen. Laws ch. 43B § 6
A charter commission shall consist of nine registered voters of the city or town elected at large and by official ballot, without party or political designation, at an election held in accordance with this chapter. The names of the candidates nominated in accordance with section five shall be placed on such ballot in alphabetical order, preceded by an instruction to the effect that a voter may vote for not more than nine persons as charter commission members whether or not he favors the election of a charter commission. The question of electing a commission to adopt or revise the charter shall be placed on such ballot in the form prescribed by the constitution.
If a majority of the votes cast upon the question of adopting or revising the charter is in the affirmative, the nine candidates receiving the highest number of votes shall be declared elected.
If a majority of the votes cast upon the question is in the affirmative, the city or town clerk shall notify the secretary of housing and livable communities of such affirmative vote and said secretary shall notify such commission of the dates for submission of their reports and the available date or dates that such report can be placed on its ballots.
Mass. Gen. Laws ch. 43B, § 43B:6