P sues D for defamation. To prove that the defamatory statement was made, P calls W1 who testifies that he was in a group of P’s business colleagues when D told the group that P was a “con man.” During its case-in-chief, D walls W2, W1’s wife, to testify that W1 suffers from frequent delusions.
P objects to D’s use of W2? How should the court rule?
Objection overruled. W2’s testimony is being offered to impeach the credibility of W1 by showing that W1 has a disability that might have affected his ability to perceive the utterance accurately, if at all. Physical and mental capacities are factors that may be considered in weighing the witness’ credibility. Ellarson v. Ellarson. These deficits bear on the potential for human error in recollection.
New York law is aligned with federal law in that both liberally permit this type of impeachment without much restriction. Such perception evidence is even more likely to come in if the witness’ credibility is key to the case. But courts have discretionary authority to direct and limit the use of such evidence.
Perception evidence is considered noncollateral (important), so extrinsic evidence (offered other than through the witness himself — in this case W1) may be used to prove it up. In the above fact pattern, W2’s testimony is considered extrinsic, and is therefore admissible, to impeach W1 by showing his possible sensory impairment (delusions).
Aside from sensory impairment, see the other nine components of witness credibility.