It has been said so many times that a party is concluded by the answers of a witness on any collateral matter, that the real rule and the reasons therefor are very generally misunderstood and frequently misapplied. Some cases and some textbooks draw a very clear distinction between impeachment as applied to a collateral matter and contradiction as applied to a collateral matter. The distinguishing feature seems to be found in whether or not the answer sought to be refuted is elicited on direct examination or cross-examination. If an answer given on direct examination is to be disproven it is called contradiction. If an answer elicited on cross-examination is to be disproven it is called impeachment. It is obvious, of course, that this is all a matter of definition and despite a confusion of terms the question of refuting answers elicited either on direct or cross-examination is really a matter of impeachment and by the better writers is generally called impeachment by contradiction. Definitions are not particularly material to our present inquiry as we are here chiefly interested in applying this rule of evidence to collateral matters.
Robert S. Macfarlane,
Notes and Comments,
Evidence: Contradiction of Collateral Matter,
Wash. L. & Rev.
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