Res judicata

What res judicata means

In practice, you will see res judicata in pleadings, motions, orders and court rules. The definition above explains the general meaning. Even so, the meaning can shift with context. Therefore, always read it alongside the rule or document where it appears.

Where res judicata comes up

For example, the term appears in these procedures:

• Affirmative Defenses (Fed. R. Civ. P. 8(c)): defenses that defeat or reduce a claim even if the plaintiff's allegations are true. Rule 8(c)(1) lists examples such as statute of limitations, res judicata, release, payment and waiver.

How to research the term

First, read the term where it actually appears. A rule, statute or court decision may define it for its own purposes. Next, check whether your court has a local rule that uses res judicata in a special way. Then look at recent decisions from courts in your jurisdiction. They show how judges apply the term today. Also, remember that state law can differ from federal law. For that reason, use our state procedures guide to find your state’s rules. Finally, confirm every source is current before you rely on it.

You can read the official rule text online for free.

Related legal terms

• Affirmative defense: a defense that defeats or reduces a claim even if the plaintiff's allegations are true, such as the statute of limitations.
• Statute of limitations: a law setting the deadline for starting a lawsuit. Limitations periods vary by claim and jurisdiction.
• Collateral estoppel: issue preclusion: an issue actually decided in a prior case may not generally be relitigated by the same parties.

Why precise terms matter

Courts read legal terms closely. As a result, knowing the exact meaning of a word helps you follow orders, rules and filings. Each glossary entry on Lawtopolis is short on purpose and links to the pages where the term is used.