Can extrinsic evidence of bias be used to impeach a witness?

The use of extrinsic evidence of bias to impeach a witness is permissible as long as it complies with the relevant court rules. Courts generally allow extrinsic evidence to show a witness's bias because it is considered critical to assessing the credibility of the witness. This type of evidence can take various forms, such as prior statements, relationships, or motives that could affect a witness's testimony.

In practice, for courts to admit extrinsic evidence, it must be relevant to the witness's credibility and must comply with rules regarding the presentation of evidence. Rules like the Federal Rules of Evidence emphasize allowing sufficient latitude for a party to demonstrate how a witness's bias may color their testimony. Thus, as long as the extrinsic evidence is presented according to appropriate court procedures and is relevant, it will be accepted for impeachment purposes.

This approach helps ensure that juries have the full context to evaluate the accuracy and reliability of a witness's testimony, which is essential for a fair trial.