Frost (plaintiff) was injured in an automobile accident, and sued the other driver for medical costs, pain and suffering, impaired earning capacity, and future expenses. Under his union health insurance plan, Frost received medical benefits from his insurer, Union Labor. Union Labor intervened in the case, claiming a right of subrogation to share in any recovery Frost might receive for medical expenses. Frost settled the claim, and the trial court found that Union Labor had a right of subrogation in the settlement for the amount it had paid to Frost, reduced by a proportion of Frost’s cost in obtaining the settlement. The Superior Court certified the subrogation question directly to this court.