§ 22.09 Untruthful Character—Prior Acts: FRE 608(b)

• Jurisdiction: United States

§ 22.09 Untruthful Character—Prior Acts: FRE 608(b)

Specific instances of conduct are admissible only if (1) the conduct reflects untruthful character, (2) its probative value outweighs the danger of unfair prejudice, (3) a good faith basis for the inquiry exists, and (4) the evidence is introduced on cross-examination (and not through extrinsic evidence—e.g., other witnesses).

Truthfulness requirement. Only prior acts probative of untruthful character are admissible. Wigmore favored limiting admissibility to "only such misconduct as indicates a lack of veracity—fraud, forgery, perjury, and the like."¹⁴⁴ For example, a witness's falsification of an application for a marriage license, college admission, or unemployment benefits falls within this rule.¹⁴⁵ In contrast, drug use and assaults do not.¹⁴⁶

Rule 403. The admissibility of Rule 608(b) evidence is entrusted to the discretion of the trial judge per Rule 403.¹⁴⁷ The danger of unfair prejudice is acute if the witness is the criminal defendant.

Good faith basis-in-fact requirement. The party inquiring into specific instances of conduct must have a good faith basis-in-fact for asking the question, especially in criminal cases where the unfair prejudice may be great. The Fourth Circuit, for example, found a due process violation where a prosecutor's questions concerning prior bad acts, offered to impeach the defendant, lacked a sufficient evidentiary foundation.¹⁴⁸

Extrinsic evidence. Rule 608(b) explicitly prohibits extrinsic evidence in this context—for example, the testimony of other witnesses who had observed the conduct—even if the testifying witness denies the conduct on cross-examination.¹⁴⁹ This restriction is intended to avoid time-consuming and distracting mini-trials on purely credibility issues.

Other theories of admissibility. Rule 608(b) is not a bar to admissibility if the proffered evidence is relevant for some other purpose. In United States v. Abel,¹⁵⁰ the prosecution offered extrinsic evidence showing that the defendant and a defense witness were members of a secret prison gang that professed a creed requiring its members to lie for each other. The defendant argued, inter alia, that the evidence violated Rule 608(b) because it was not sufficiently probative of truthfulness and was introduced through extrinsic evidence. Without deciding the Rule 608(b) issue, the Supreme Court held the evidence admissible as impeachment for bias. According to the Court, "there is no rule of evidence which...