MBE Rules · Civil Procedure

Res judicata (claim preclusion)

The rule

A valid, final judgment on the merits bars the same parties (or those in privity) from re-litigating the same CLAIM. Claim = the transaction or occurrence giving rise to the original suit. Bars not only what WAS raised but what COULD HAVE BEEN.

In plain English

Once a court decides a case, you can't sue the same person again over the same issue or related issues that you could have brought up the first time.

Worked example

The buyer sues the seller for breach of contract and loses. Later, the buyer tries to sue the seller again for fraud related to the same contract. The court won't allow it because the buyer should have raised all related claims in the first case.

Memory hook

One shot, one claim, no redo. Once a valid judgment hits, you can't re-litigate what was or could've been raised.

The trap

Students think: only identical issues are barred. Wrong, because it covers the entire transaction. The actual test is whether the same claim could've been litigated.

How examiners test it

The MBE loves: two suits between same parties, seemingly different issues. Trap: students miss that it's the same transaction. Remember, all claims arising from the same occurrence are barred.

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