Mass. Gen. Laws ch. 85 § 2C
The department, for the purpose of promoting public safety and convenience, may authorize by any rule or regulation adopted under this section with such limitations, if any, as may be deemed proper, the colonel of state police and the principal police official of the police department of a city or town, or such sergeants or officers of higher rank as said officers or officials may from time to time designate, to remove, to some convenient place, through the agency of a person or persons in the employ of said police or police force, or by an independent contractor selected on the basis of competitive bids, any vehicle, except a vehicle owned by the commonwealth or a political sub-division thereof or by the United States or an instrumentality thereof or registered by a member of a foreign diplomatic corps or by a foreign consular officer who is not a citizen of the United States and bearing a distinctive number plate or otherwise conspicuously marked as so owned or registered, parked or standing on any part of a state highway in such a manner as to impede in any way the removal or plowing of snow or ice or parked or standing in violation of any rule or regulation adopted under section two which prohibits the parking or standing of all vehicles on such highway or portion thereof at such time and recites that whoever violates it shall be liable to charge for the removal and storage of the vehicle as well as subject to punishment by fine. Liability may be imposed for the reasonable cost of such removal, and for the storage charges, if any, resulting therefrom, upon the owner of such vehicle.
Mass. Gen. Laws ch. 85, § 2C