Mass. Gen. Laws ch. 140 § 173A
Whenever a complaint is sought in a district court for a violation of an ordinance or by-law, made under the provisions of section one hundred and seventy-three, the clerk shall send a written notice to the person complained against stating that such a complaint has been sought and will issue unless such person appears before such clerk and confesses the offense either personally or through an agent duly authorized in writing, or by mailing to such clerk, with the notice the fine provided herein. The fine for the first offense committed by a person shall be $50. The fine for a second offense shall be $100. The fine for a third offense shall be $300. For a fourth or subsequent offense, the fine shall be $500 and the municipality may order the animal spayed or neutered. Payment shall be made only by money order or check. Notwithstanding the foregoing procedure and schedule of fines, but subject to all other provisions of this section, a city or town may, by ordinance or by-law, provide for an alternative procedure and a different schedule of fines; provided, however, that the fines shall not be lower than those stated in this section. Notwithstanding this section, a municipality may seek a remedy under section 157 for a nuisance dog.
Proceedings under this section shall not be deemed criminal; and no person notified to appear before the clerk of a district court as provided herein shall be required to report to any probation officer, and no record of the case shall be entered in the probation records.
If a person notified to appear, as hereinbefore provided, fails to appear or pay the fine within twenty-one days of the sending of the notice, or having appeared, does not desire to avail himself of the procedure established by this section, the clerk shall issue the complaint and the procedure established for criminal cases shall be followed.
If any person fails to appear in accordance with the summons issued upon such complaint, the clerk of the court shall send such person, by registered mail, return receipt requested, a notice that the complaint is pending and that, if the person fails to appear within twenty-one days from the sending of such notice, a warrant for his arrest will be issued.
Mass. Gen. Laws ch. 140, § 173A