Mitchill v. Lath

247 N.Y. 377, 160 N.E. 646 (1928)

New York Court of Appeals · 1928

• Parol evidence rule
• Collateral agreement test
• Naturally would have been included
• Total integration

Facts

Mrs. Mitchill agreed to purchase a farm from the Lath brothers in New York. During negotiations, Mr. Lath allegedly promised that he would remove an unsightly icehouse sitting on a neighboring parcel he owned as an inducement for Mrs. Mitchill to complete the purchase. That promise did not appear anywhere in the written contract of sale. The written agreement was detailed: it set out the purchase price, the subject matter, and the financing terms, and on its face appeared to be a full and complete statement of the parties’ obligations. After the sale closed, Mr. Lath refused to remove the icehouse. Mrs. Mitchill sued for breach of contract, arguing that the oral promise was enforceable as a collateral agreement separate from the land sale and therefore not barred by the parol evidence rule.

Holding

The New York Court of Appeals held that the parol evidence rule barred admission of the oral promise. The written contract was a complete integration, and the alleged promise to remove the icehouse failed the court’s test for collateral agreements: it was the type of term that parties in a land sale would ordinarily be expected to write down if they intended it to bind.

Reasoning

Judge Andrews announced a three-part test for determining whether an alleged oral promise may come in alongside a written contract as a collateral agreement. The promise must be (1) collateral in form, meaning a genuinely separate side deal rather than a term of the written transaction; (2) consistent with, and not contradicting, the express or implied provisions of the writing; and (3) of a kind that the parties would not ordinarily be expected to embody in the writing. The third prong did the dispositive work in this case. The court found that the icehouse promise was so closely connected to the property sale that a reasonable buyer who cared about removing the structure would have insisted on its inclusion in the contract. Because the promise would naturally have been included in the writing, admitting extrinsic evidence of it would undermine the writing’s integrity.

That third prong is narrower than R2d § 216(2), which asks whether the alleged term is one that might naturally have been omitted from the writing. The shift from “would have been included” to “might naturally have been omitted” is not stylistic; it moves the burden and the result. Under the Restatement formulation, a term with a plausible explanation for its omission survives; under Mitchill, the same term may fail because a careful party would have written it down. The Mitchill approach reflects the Williston-textualist position: written contracts define the deal, and parties who want something in the deal put it in the contract.

Why it matters

The casebook assigns Mitchill as the anchor case for Chapter 17’s treatment of the parol evidence rule. It illustrates the rule in a concrete, sympathetic set of facts (Mrs. Mitchill may well have received that oral promise) and then applies the rule without softening. The case introduces the collateral-agreement exception, which sounds like a path around the PER, and immediately shows why it is a narrow path: the very test for collateral status tends to exclude the promises litigants most want to admit. Mitchill sits at the Williston pole of the American PER debate. PG&E v. Thomas Drayage occupies the Corbin pole, arguing that apparent clarity is itself a contextual judgment. The casebook uses both cases together to map the field: plain-meaning courts (New York, Pennsylvania) treat the writing as the inquiry’s endpoint; contextualist courts (California) treat apparent clarity as the beginning of an inquiry into what the language could reasonably mean. A student who can explain both positions, and explain what turns on the choice, has mastered the core parol-evidence question.

Mitchill v. Lath, 247 N.Y. 377, 160 N.E. 646 (1928).