How To Prove A California Res Judicata (Claim Preclusion) Defense

In California, a defense of Res Judicata (Claim Preclusion) is defined as:
Res Judicata, also known as Claim Preclusion, bars a person from re-litigating a claim or cause of action where the same claim has been litigated on its merits by the same parties, and a final decision has been rendered by a court.
It simply means:
One party can’t sue another twice for the same claim.
There are 4 elements of the defense:
- Element 1. There is an existing lawsuit. Res Judicata, or claim preclusion, means that if a lawsuit is already ongoing, you can’t bring the same issue or claim again in a new case; the existing lawsuit must be resolved first before any related claims can be pursued.
Facts that might support this element look like:
* A lawsuit was filed on January 15, 2023, in the Superior Court of Example County, involving the same parties and issues as the current case.
* The previous lawsuit resulted in a final judgment on March 10, 2023, which addressed the merits of the claims presented.
* The plaintiff in the current case was also the plaintiff in the earlier lawsuit, asserting the same legal claims.
* The defendant in the current case was the defendant in the prior lawsuit, and both cases involve the same underlying facts.
* The parties had a full and fair opportunity to litigate the issues in the earlier lawsuit, leading to a conclusive resolution. - Element 2. A claim raised in the lawsuit was identical to a claim litigated in a prior proceeding. A claim in the current lawsuit is the same as one that was already decided in a previous case, meaning it cannot be brought up again because the earlier decision should be respected and not re-litigated.
Facts that might support this element look like:
* The plaintiff previously filed a lawsuit against the defendant in 2021, alleging the same breach of contract.
* The prior case was fully adjudicated, resulting in a final judgment in favor of the defendant.
* The claims in both the current lawsuit and the prior proceeding arise from the same set of facts and circumstances.
* The parties involved in both cases are identical, with the same plaintiff and defendant.
* The legal issues presented in the current claim were already determined in the earlier litigation. - Element 3. The prior proceeding resulted in a final judgment on the merits. The prior case was fully decided by a court, meaning it reached a final conclusion on the main issues, which prevents the same parties from relitigating those issues in a new case.
Facts that might support this element look like:
* The prior proceeding concluded with a judge issuing a written decision that addressed all substantive issues raised by the parties.
* The court in the prior proceeding entered a final judgment that resolved the case, leaving no further matters to be litigated.
* The parties in the prior proceeding had a full opportunity to present their evidence and arguments before the court rendered its decision.
* The final judgment from the prior proceeding was not appealed, making it conclusive and binding on the parties involved.
* The issues decided in the prior proceeding were essential to the final judgment, demonstrating that the case was fully adjudicated on its merits. - Element 4. The party against whom the doctrine is being asserted was a party or in privity with a party to the prior proceeding. This means that the person being challenged in the current case was either directly involved in the earlier case or had a close relationship with someone who was, making them bound by the earlier decision.
Facts that might support this element look like:
* The plaintiff in the current case was also the plaintiff in the prior proceeding, directly involving the same parties.
* The defendant in the current case was a co-defendant in the previous lawsuit, sharing a common interest in the outcome.
* Both parties were represented by the same legal counsel in the earlier case, establishing a clear connection between the two proceedings.
* The issues litigated in the prior proceeding were directly related to the claims being made in the current case, indicating a shared legal context.
* The current plaintiff was a witness in the prior proceeding, demonstrating their involvement and connection to the earlier case.
(See Planning & Conservation League v. Castaic Lake Water Agency (2009) 180 Cal.app.4th 210, 226. People v. Barragan, 83 P. 3d 480 – Cal: Supreme Court 2004.)
If you’re representing yourself in court and plan to assert a Defense of Res Judicata (Claim Preclusion), having a Personal Practice of Law at Courtroom5 is essential. You’ll need to make informed decisions about what to file at each phase of your case and prepare legal documents that are supported by thorough legal research and a strong analysis of the facts. Equip yourself with the tools and knowledge necessary to effectively present your Defense of Res Judicata.
Prove Your CA Res Judicata (Claim Preclusion) Defense
U.S. Civil Cases Only