Collateral Estoppel (Issue Preclusion)
Collateral estoppel (issue preclusion) prevents relitigation of specific issues of fact or law that were actually litigated, necessarily decided, and essential to the judgment in a prior proceeding between the same parties.
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Exam Tip
Collateral Estoppel = ISSUE preclusion (not claim). Five elements: identical, actually litigated, necessarily decided, final judgment, fair opportunity. Parklane = limits on offensive use. No mutuality required.
What is Collateral Estoppel?
Collateral estoppel, also called issue preclusion, bars relitigation of specific issues (not entire claims) that were decided in a prior proceeding. Unlike res judicata which bars claims, collateral estoppel bars issues.
Essential Elements
| Element | Requirement |
|---|---|
| Identical Issue | Same issue of fact or law |
| Actually Litigated | Issue was contested and submitted for determination |
| Necessarily Decided | Essential to the judgment |
| Valid Final Judgment | Prior judgment was valid and final |
| Full and Fair Opportunity | Party had chance to litigate |
Offensive vs. Defensive Use
| Type | Definition | Special Rules |
|---|---|---|
| Defensive | Defendant uses to prevent plaintiff from relitigating issue plaintiff lost | Generally allowed |
| Offensive | Plaintiff uses against defendant who lost issue before | Subject to restrictions (Parklane) |
California-Specific Rules
- No mutuality required (Bernhard v. Bank of America)
- Different burden of proof may preclude issue preclusion
- Criminal acquittal doesn't preclude civil finding (different standards)