New York Law (NYLE) Practice Exam

Under what condition can an attorney impeach a witness's credibility using extrinsic evidence?

1. To establish the witness's expertise on a subject.

2. To discredit the witness's credibility on an immaterial issue.

3. To provide context for the witness's testimony.

4. To clarify the credibility of the opposing party's claims.

The correct answer is: To discredit the witness's credibility on an immaterial issue.

An attorney can impeach a witness's credibility using extrinsic evidence primarily when addressing specific character traits or dishonest actions of the witness, particularly if those traits are relevant to the witness's reliability or truthfulness. In this context, discrediting a witness on an immaterial issue—meaning a subject not central to the case but still indicative of the witness’s character or honesty—allows for the introduction of extrinsic evidence. This evidence may include prior inconsistent statements or evidence of prior dishonest behavior that illustrates a pattern of untruthfulness relevant to the witness's overall credibility. While establishing expertise, providing context, or clarifying claims can be important in different contexts during a trial, they do not effectively justify the use of extrinsic evidence for impeachment purposes. The focus of impeachment is primarily on the witness's truthfulness and reliability, particularly concerning issues that may affect their credibility concerning the material facts of the case. Therefore, impeachment based on an immaterial issue serves as a valid avenue for introducing extrinsic evidence that challenges the witness's overall credibility.