Notwithstanding the provisions of section sixty-two punishment duty shall not be imposed upon any police officer or firefighter, who is employed by a city or town subject to the provisions of this chapter, unless such police officer or firefighter assents thereto. This section shall take effect in a city or town upon its acceptance and shall become ineffective in any city or town which rescinds its acceptance in the same manner as it was accepted.
Mass. Gen. Laws ch. 31, § 62A