Civil Procedure · defense
Res judicata, also known as claim preclusion, prevents parties from relitigating issues that have already been judged in a final verdict by a competent court. It serves to promote the finality of judgments and judicial efficiency.
There must be a final judgment in a previous case that concluded the matter.
What to prove: It must be shown that the prior case resulted in a final judgment on the merits, not subject to further appeal.
The parties in the subsequent action must be the same as those in the prior action, or in privity with them.
What to prove: The identity of parties or their legal representatives in both cases must be established.
The claim or cause of action in the subsequent case must be substantially the same as that in the prior case.
What to prove: It must be demonstrated that the facts and issues presented in both cases arise from the same transaction or nucleus of operative facts.
The burden lies with the defendant asserting the res judicata defense to show that all elements are satisfied, usually by the preponderance of the evidence standard.
Be prepared to analyze different fact patterns where res judicata may apply or fail based on the identity of parties and causes of action.