Legal Memorandum: Impeachment of Testimony in TX

Issue: What is the standard for admissibility to impeach or contradict testimony in Texas?

If a witness asserts that a particular fact is true, other witnesses may be called to contradict that assertion, if the contradictory testimony is relevant.  Zimmerer v. Smyrl, 670 S.W. 2d 273, 274 (Tex. App. – 1st 1983).  Incidental facts are relevant when their existence tends to establish to some degree of certainty a principal fact in issue.  Ledisco Fin. Sers. V. Viracola, 533 S.W. 2d 951, 958 (Tex. App. – 6th 1976).  In addition, evidence on collateral matters that affects the credibility of a witness is “clearly admissible.”  Houston Lighting & Power Co. v. Sue, 644 S.W. 2d 835, 842 (Tex. App. – 13th 1982).  The trial court should be liberal in its admission of evidence of this nature.  Trial courts have the discretion to receive “any evidence which gives promise of exposing falsehood.”  Id.

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