Ace the 2026 MBE Evidence Exam: Unleash Your Legal Eagle Powers!

Impeachment based on bias is allowed when a witness has a relationship with a party that could influence their testimony. If the church itself is a party in the case, the witness’s affiliation with that church signals a real motive to testify in a way that favors the church’s position, making the testimony less credible on issues the church has an interest in. That potential bias is exactly the kind of information courts look for to assess reliability, so the affiliation is admissible for impeachment.

The First Amendment does not bar this; it prohibits using religious beliefs or opinions to attack credibility, but it does not forbid showing a relevant affiliation that indicates bias. And the witness’s consent isn’t required for this line of impeachment.