Mass. Gen. Laws ch. 130 § 98
In each city and town bordering on coastal waters the mayor or the selectmen, as the case may be, shall appoint a person or persons, qualified by training and experience in the field of shellfishery management, as shellfish constables or deputy shellfish constables. A person having successfully completed the shellfish wardens training course at the Massachusetts Maritime Academy as certified by said academy, shall be considered qualified by training and experience in the field of shellfishery management and shall be eligible for appointment as a shellfish constable or deputy shellfish constable. Such shellfish constables and deputy shellfish constables shall be appointed for terms of three years, and may be reappointed. They shall, subject to the appointing authority, initiate, promote and manage shellfisheries in such city or town and shall make or cause to be made such studies as may be necessary to enhance the value of such shellfisheries. They shall enforce all statutes, ordinances, by-laws, rules and regulations relative to shellfish in such city or town. They shall, for the enforcement of sections thirty-one, thirty-seven, forty-one, forty-three and forty-four, have the authority granted to natural resource officers, subject to written rules and regulations of the commissioner. In the performance of his duties, a shellfish constable or deputy shellfish constable may request any person who he has cause to believe is engaged in unlawful shellfishing, is in unlawful possession of shellfish, or is in possession of shellfish unlawfully taken, to display forthwith for inspection all shellfish in his possession, and he may arrest without a warrant any person refusing or failing to comply with such request.
Upon the appointment of a shellfish constable or deputy shellfish constable under this section, the appointing authority shall forthwith notify the director of the division of marine fisheries and the director of the division of law enforcement.
Mass. Gen. Laws ch. 130, § 98