Massachusetts General Laws Part III. Courts, Judicial Officers and Proceedings in Civil Cases (Ch. 211-262) Ch. 231, § 6B

In any action in which a verdict is rendered or a finding made or an order for judgment made for pecuniary damages for personal injuries to the plaintiff or for consequential damages, or for damage to property, there shall be added by the clerk of court to the amount of damages interest thereon at the rate of twelve per cent per annum from the date of commencement of the action even though such interest brings the amount of the verdict or finding beyond the maximum liability imposed by law.