Parol Evidence Rule
The parol evidence rule prevents parties from introducing evidence of prior or contemporaneous oral or written agreements to contradict, vary, or add to the terms of a fully integrated written contract.
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Exam Tip
Parol evidence rule only applies to INTEGRATED writings. Three exceptions: formation defects, condition precedent, subsequent modifications.
What is the Parol Evidence Rule?
The parol evidence rule bars admission of extrinsic evidence to contradict or supplement terms of a writing intended as the final expression of the agreement.
Integration
| Type | Effect |
|---|---|
| Complete Integration | No contradicting OR supplementing |
| Partial Integration | No contradicting, MAY supplement |
| No Integration | Parol evidence freely admissible |
Exceptions
| Exception | Purpose |
|---|---|
| Formation Defects | Fraud, duress, mistake |
| Condition Precedent | Contract wouldn't take effect until condition met |
| Ambiguity | To clarify ambiguous terms |
| Subsequent Modifications | Agreements made AFTER the writing |
UCC Approach
More liberal - course of performance, dealing, and usage of trade always admissible.