Section 2.36 Parol Evidence Rule

• Library: Contracts 2016 Supp

V. (§2.36) Parol Evidence Rule

When two parties have made a contract and have expressed it in a writing
to which they have both assented as the complete and accurate integration
of that contract, evidence, whether parol or otherwise, of antecedent understandings and negotiations will not be admitted for the purpose of varying or contradicting the writing.

6 Arthur L. Corbin, Corbin on Contracts § 573 (1960, reprinted 2002). The parol evidence rule is a rule of substantive law and not a rule of evidence. Even if the evidence was received without objection, it must be ignored once the question is raised. Commerce Trust Co. v. Watts, 231 S.W.2d 817 (Mo. 1950). The rule excludes only evidence of transactions occurring before or contemporaneous with the written agreement; it does not exclude evidence of subsequent transactions. George F. Robertson Plastering Co. v. Magidson, 271 S.W.2d 538
(Mo. 1954). Section 400.2-202, RSMo 2000, covers the parol evidence rule as it applies to contracts for the sale of goods. In general it follows the Corbin approach. See V.A.M.S. § 400.2-202, UCC cmt. 3 (1994).

The rule does not apply to any writing unless the parties have intended the writing to be a final expression of their agreement, and any relevant evidence is admissible to show that the writing is not the final agreement. 6 Corbin on Contracts § 588 (1960, reprinted 2002). Evidence is admissible to show that a writing is not to become a contract until the occurrence of some condition. For example, parol evidence is admissible to show that a writing purporting to be a land contract was not to be binding unless the vendee was able to obtain a loan from a bank. Farmers Ins. Exch. v. Farm Bureau Mut. Ins. Co., 522 S.W.2d 779 (Mo. banc 1975). Such evidence does not vary the terms of the writing; it shows only that the writing is not a contract. It should be noted, however, that parol evidence is not admissible to show that a duty under a contract was to arise only on the occurrence of a condition. Such evidence would vary the terms of the writing by showing that what appeared to be an unconditional promise was, in fact, conditional. Scullin Steel Co. v. Miss. Valley Iron Co., 273 S.W. 95 (Mo. banc 1925).

Parol evidence is admissible for the purpose of interpreting a written contract. Hardesty v. Mr. Cribbin’s Old House, Inc., 679 S.W.2d 343
(Mo. App. E.D. 1984). Also, parol evidence may be used to prove that the writing is not the agreement the parties entered into. See Arie v. Intertherm, Inc., 648 S.W.2d 142 (Mo. App. E.D. 1983), overruled on other grounds by Johnson v. McDonnell Douglas Corp., 745 S.W.2d 661 (Mo. banc 1988).

The rule excludes evidence for the purpose of varying or contradicting the writing; it does not forbid the use of evidence to show that the agreement was entered into as a result of mistake, Fulton v. Bailey, 413 S.W.2d 514 (Mo. 1967), fraud, duress, or undue influence, Employers’ Indem. Corp. v. Garrett, 38 S.W.2d 1049 (Mo. 1931).
In these cases, however, the parol evidence...