Also known as: parol evidence · parole evidence rule · parol evidence rule
Written by attorneys · grounded in primary & secondary sources — see below
A substantive rule of contract law that renders inoperative prior agreements, whether written or oral, to the extent they contradict or fall within the scope of a later integrated writing adopted by the parties as a complete and exclusive statement of terms.
Pierce Patterson sold land to Paige Porter under a contract containing a merger clause declaring the writing complete. After closing the deed omitted an oral promise to repair a fence. Porter sued to enforce the promise. The court held the parol evidence rule and merger discharged the prior term because it was not restated in the deed.
Prime Logistics and Progressive Healthcare signed a forty-page supply contract with an integration clause. Progressive sought to enforce an earlier oral volume commitment omitted from the writing. The court first determined the writing was completely integrated before applying the parol evidence rule to exclude the prior term.
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Phuong Pham conveyed land by absolute deed to Platinum Partners to secure a loan. A contemporaneous side letter stated the deed was security only. When Pham repaid, Partners refused reconveyance. The court admitted parol evidence to establish the deed operated as a mortgage and ordered reconveyance.
Peak Performance emailed a term sheet to Patricia Patel describing loan terms. Patel later signed a formal agreement that expressly referenced the term sheet. When Patel sued to enforce omitted protections, the court treated the term sheet as incorporated rather than excluded parol.
Phoebe Park contracted in writing with Pearl Porter to refurbish equipment. After discovering hidden damage the parties signed a written change order raising the price. When Park later refused the increase, the court admitted the change order because the parol evidence rule does not govern post-formation modifications.
Patricia Patel signed a license agreement with Progressive Healthcare after miscalculating her server needs by a factor of ten. Patel sought to avoid the contract on mistake grounds. The court refused to admit prior projections because the parol evidence rule precludes extrinsic evidence offered to alter an integrated writing.
The court makes this determination as a preliminary question of law by examining the writing's completeness, specificity, and any merger clause. If the document reasonably appears to be a complete and exclusive statement of terms, it is treated as integrated.
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No. The rule applies only to prior or contemporaneous agreements. Evidence of subsequent modifications or waivers is admissible because those agreements arise after the writing is executed.
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Parol evidence is admissible to prove the deed was given only as security when a side letter or other contemporaneous writing shows the parties' intent. Upon repayment the grantee must reconvey.
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Under the merger doctrine those promises are typically discharged unless they involve fraud, mutual mistake, or collateral agreements not intended to merge. The deed becomes the sole measure of the grantor's obligations.
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Yes when the writing is only partially integrated. Such evidence may explain or supplement the agreement provided it does not contradict any term of the integrated writing.
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…that Burger King officials had given them oral assurances concerning assignment, the District Court found that pursuant to the parol evidence rule any such assurances "even if they had been made and were misleading were joined and merged" into the final agreement. 7 Record 648. [^maj-7]: Although Rudzewicz and MacShara dealt with the…