Parol Evidence Rule Extrinsic Evidence Rule Mündlichkeitsgrundsatz Extrinsic Evidence Rule Regla de la evidencia parol Regla de la evidencia parol Règle de preuve par témoignage oral כלל הראיות הפרוליות पैरोल साक्ष्य नियम 口証ルール Regra da prova testemunhal 口证规则 The Parol Evidence Rule is a legal defense in civil litigation that prohibits the introduction of oral or written evidence that contradicts the terms of a written contract.