Preclusion
One bite at the apple. Claim preclusion kills the lawsuit you should have brought the first time; issue preclusion kills the question you already lost. Keep the two tests separate and the points follow.
- Kills the whole second lawsuit
- Same claimant vs. same defendant
- Valid final judgment on the merits
- Same claim = same transaction or occurrence
- Blocks what you litigated and what you should have
- Kills one issue inside a new case
- Issue actually litigated and determined
- Essential to the first judgment
- Used only against a Case 1 party
- Strangers may sometimes use it—never be bound by it
Claim preclusion, element by element
1. Same claimant, same defendant. The parties must appear in the same configuration—A-v-B, then A-v-B. B suing A later is a different case (that's counterclaim territory).
2. Valid final judgment on the merits. 3. Same claim—majority rule: everything arising from the same transaction or occurrence. All theories, all damages, one suit.
Not “on the merits”: dismissals for jurisdiction, venue, or failure to join a required party—and voluntary dismissals without prejudice. Nearly everything else (including default) counts.
Liv's van hits Lana. Lana sues for her car damage and wins. She then sues Liv again for her back injury from the same crash—barred. One occurrence = one claim; the personal-injury and property damages had to travel together.
Issue preclusion, element by element
1. Valid final judgment on the merits. 2. The same issue was actually litigated and determined—contested and decided, not defaulted or stipulated. 3. The issue was essential to the judgment. 4. Asserted against someone who was a party (or in privity) in Case 1—due process (Taylor v. Sturgell).
Defaults and stipulations aren't “actually litigated.” Alternative holdings—two independent grounds, either sufficient—often preclude on neither, since neither was strictly essential. A finding the judgment doesn't rest on binds no one.
In Lana v. Liv, the jury finds Liv ran the red light. In a second case about the same crash, that finding can bind Liv—she litigated and lost it. It can never bind Rosa, who wasn't a party to Case 1, no matter how identical the facts.
Who may wield it: nonmutual estoppel
The old mutuality rule—only a Case 1 party could invoke a Case 1 finding—has collapsed. What replaced it is asymmetric:
- A new defendant shields itself with the plaintiff's earlier loss
- The plaintiff already had a full and fair chance to litigate
- Discourages plaintiff forum-hopping
- A new plaintiff wields an earlier finding as a sword
- Allowed when: the new plaintiff couldn't easily have joined Case 1; the defendant had full incentive to litigate; no inconsistent prior judgments; no procedural advantages missing in Case 1
- Court discretion (Parklane Hosiery)
Lana sues Noodle Corp. claiming its espresso machine is defective and loses on that issue. When she sues the distributor next, the distributor uses her loss defensively—fine. And after Rosa beats Noodle Corp. on the defect issue, a new plaintiff may borrow that win offensively—but only if the Parklane fairness factors line up.
On any preclusion question, answer three things in order: which flavor (claim vs. issue)? are the elements met? and who is it being used against—were they a party (or in privity) the first time? The third question is where most wrong answers die.
Where the points are
The traps examiners actually set.
- Most tested
- Claim-splitting (property damage now, personal injury later—barred); “actually litigated AND essential” for issue preclusion; nonmutual offensive estoppel's fairness factors.
- Classic traps
- Binding a Case 1 stranger (due process forbids it); treating a default as “actually litigated” (claim preclusion yes, issue preclusion no); a jurisdictional dismissal as “on the merits” (it isn't); alternative findings neither of which was essential.
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