Section 18.21 Scope

• Library: Evidence 2017

A. (§18.21) Scope

The best evidence rule applies whenever a party is trying to prove the contents or terms of a writing. Chevalier v. Dir. of Revenue, State of Mo., 928 S.W.2d 388, 391–92 (Mo. App. W.D. 1996). “[A] witness must be purporting to testify as to his or her observation of the operative terms of a substantive written document.” Id. at 392. Original writings are favored in this situation because, at the very least, oral testimony may be based on a misunderstanding or misinterpretation of a document’s terms. Id. Obviously, this can be particularly dangerous when the terms of important documents such as deeds, wills, or contracts are at issue. A slight variation in the recitation of a critical term could cause the case to be wrongly decided. Cooley v. Dir. of Revenue, State of Mo., 896 S.W.2d 468, 470 (Mo. banc 1995).

The best evidence rule does not apply when a party is trying to prove a fact independent of a document’s terms. Chevalier, 928 S.W.2d at 391–92. A police officer may, for example, testify about the officer’s observation of a breathalyzer result even though the officer recorded the result in...