Collateral Estoppel: Loosening the Mutuality Rule in Tax Litigation
Collateral estoppel is an aspect of the doctrine of res judicata that precludes relitigation of issues previously adjudicated. A judgment in a prior action may be held conclusive as to issues in a subsequent case. even though the later case technically involves a different cause of action. The rule of collateral estoppel seeks to conserve judicial energy, promote confidence in the judicial system, avoid litigant expense, promote community peace and reliance on judgments, and minimize inconsistent results. Countervailing policy concerns are the right of each person to have his day in court, the fear of increased litigation, the danger of perpetuating error, the need for flexibility, and other considerations of fairness. Whether a court will apply collateral estoppel in a certain case will often be determined by a weighing of these conflicting policies.