Res judicata is the generic term for a group of related concepts concerning the conclusive effects given final judgments. Within this general doctrine there are two principal categories: (1) claim preclusion—also known as res judicata; and (2) issue preclusion—also known as collateral estoppel.
These legal doctrines generally preclude litigants from relitigating claims and issues that were previously litigated to a final resolution or judgment.
In Hawaii, res judicata, also known as claim preclusion, prevents parties from relitigating a claim that has already been finally adjudicated in a court of law. Once a final judgment has been rendered on the merits of a case, the same parties cannot bring the same claim again in any Hawaii court. Similarly, issue preclusion, or collateral estoppel, bars the relitigation of specific issues that were already decided in a previous lawsuit. For issue preclusion to apply, the issue must have been actually litigated, essential to the previous judgment, and determined by a valid and final judgment. These doctrines are designed to promote judicial efficiency, respect court decisions, and protect parties from the burden of multiple lawsuits on the same matter. Both federal and state courts in Hawaii adhere to these principles, which are grounded in common law and reinforced by Hawaii state statutes and case law.