(a) Two or more municipalities may jointly perform any function that each municipality is required to perform individually under this title by entering into an agreement pursuant to this section. Any such agreement shall be negotiated and shall contain all provisions upon which each participating municipality agrees. Any such agreement shall establish a process for amendment of, termination of and withdrawal from such agreement. Any proposed agreement shall be submitted to the legislative body of each participating municipality for a vote to ratify or reject such agreement. The legislative body of each participating municipality shall provide an opportunity for public comment prior to any such vote. For purposes of this section, providing an opportunity for public comment does not require a legislative body to conduct a public hearing.

(b) For any municipality in which the legislative body is the town meeting, such legislative body may, by resolution, vote to delegate its authority to ratify or reject a proposed agreement to the board of selectmen, provided such board of selectmen provides an opportunity for public comment in accordance with this section.

(c) A copy of any such agreement entered into by two or more municipalities pursuant to this section shall be filed with the municipal clerk of each participating municipality and the Secretary of the State not later than seven days after the legislative body of the last participating municipality to ratify such agreement so ratifies such agreement.