Mass. Gen. Laws ch. 163 § 12
The department of its own motion or upon petition of any interested party may, if after notice and a hearing it finds that such action is necessary for the protection of the public, require any corporation doing business under this chapter to furnish security by bond and/or otherwise, in such amount and of such character as it may, from time to time, determine and approve, for the payment of any final judgment which may be rendered against such corporation for any injury to person or property or for damages for causing the death of any person, by reason of any negligent or unlawful act, on the part of such corporation, its agents or employees, in the use or operation of vehicles by said system known as trolley motor or trackless trolley. Any bond so required shall run to the state treasurer as obligee. Any person so injured or damaged, or his executor or administrator, or the executor or administrator of any person whose death was so caused, may enforce payment of such judgment by suit on such bond in the name of the state treasurer, and in such suit the court may make any appropriate order for the application of any security required as aforesaid.
Mass. Gen. Laws ch. 163, § 12