Parol Evidence Rule

The parol evidence rule is a substantive rule of common law contract doctrine that, once parties have reduced their agreement to a final written document, generally bars the introduction of extrinsic evidence, such as prior or contemporaneous oral statements, to contradict or vary the terms of that writing. Its name derives from the Anglo-Norman French parol, meaning word of mouth or oral, reflecting its origin in a period when court pleadings were made orally; the rule rests on the premise that when parties deliberately memorialize their bargain in a single written document, that document, not earlier oral discussion, should govern its terms. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/