Mass. Gen. Laws ch. 231, § 140A

In an action to recover damages for injuries to person or property, or for death, or consequential damages, so called, sustained by reason of a motor vehicle accident, a judgment entered by agreement of the parties, without a hearing on the merits, shall not operate as a bar to an action brought by a defendant in the action in which such judgment was entered, unless such agreement was signed by the defendant in person.