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 Minnesota, res judicata, or claim preclusion, prevents a party from relitigating a claim that has already been finally adjudicated in a previous lawsuit. This doctrine applies when the earlier and later suits have identical parties or their privies, involve the same cause of action, and the earlier suit resulted in a final judgment on the merits. Issue preclusion, or collateral estoppel, on the other hand, prohibits the re-litigation of factual or legal issues that were actually litigated and essential to the judgment in a prior action between the same parties or their privies. Minnesota courts require that the issue was necessary and essential to the resulting judgment, and that the parties had a full and fair opportunity to litigate the issue in the previous proceeding. These doctrines are meant to promote judicial efficiency, maintain consistency, and protect parties from the burden of multiple lawsuits.