Mass. Gen. Laws ch. 58 § 14
In 2019 and every 2 years thereafter, the commissioner, on or before June 1, shall determine the fair cash valuation of state-owned land located within each city or town under section 13. To assist in making the determination the commissioner may require oral or written information from any officer or agent of the commonwealth or of any city or town therein and from any other inhabitant thereof, and may require such information to be on oath. Such officers, agents and persons, so far as able, shall furnish the commissioner with the required information in such form as the commissioner may indicate, within 15 days after being so requested by the commissioner.
With respect to land held by the division of watershed management in the department of conservation and recreation for the purposes named in section 5G of chapter 59, the commissioner shall, by June 1, also determine the fair cash valuation of such land in each city or town by the same method as provided in section 13 for determining the fair cash valuation of state-owned land and notify the division of the valuations.
Mass. Gen. Laws ch. 58, § 14