469 U.S. 45 (1984)
Respondent John Abel and two cohorts were indicted for robbing a savings and loan in Bellflower, Cal., in violation of 18 U. S. C. §§ 2113(a) and (d). The cohorts elected to plead guilty, but respondent went to trial. One of the cohorts, Kurt Ehle, agreed to testify against respondent and identify him as a participant in the robbery.1
Respondent informed the District Court at a pretrial conference that he would seek to counter Ehle’s testimony with that of Robert Mills. Mills was not a participant in the robbery but was friendly with respondent and with Ehle, and had spent time with both in prison. Mills planned to testify that after the robbery Ehle had admitted to Mills that Ehle intended to implicate respondent falsely to receive favorable treatment from the Government. The prosecutor in turn disclosed that he intended to discredit Mills’ testimony by calling Ehle back to the stand and eliciting from Ehle the fact that respondent, Mills, and Ehle were all members of the “Aryan Brotherhood,” a secret prison gang that required its members always to deny the existence of the organization and to commit perjury, theft, and murder on each member’s behalf.2 Defense counsel objected to Ehle’s proffered rebuttal testimony as too prejudicial to respondent. After a lengthy discussion in chambers the District Court decided to permit the prosecutor to cross-examine Mills about the gang, and if Mills denied knowledge of the gang, to introduce Ehle’s rebuttal testimony concerning the tenets of the gang and Mills’ and respondent’s membership in it.3
At trial Ehle implicated respondent as a participant in the robbery. Mills, called by respondent, testified that Ehle told him in prison that Ehle planned to implicate respondent falsely. When the prosecutor sought to cross-examine Mills concerning membership in the prison gang, the District Court conferred again with counsel outside of the jury’s presence, and ordered the prosecutor not to use the term “Aryan Brotherhood” because it was unduly prejudicial. Accordingly, the prosecutor asked Mills if he and respondent were members of a “secret type of prison organization” which had a creed requiring members to deny its existence and lie for each other. When Mills denied knowledge of such an organization the prosecutor recalled Ehle.4
Ehle testified that respondent, Mills, and he were indeed members of a secret prison organization whose tenets required its members to deny its existence and “lie, cheat, steal [and] kill” to protect each other.5 Ehle then further described the organization and testified that “in view of the fact of how close Abel and Mills were” it would have been “suicide” for Ehle to have told Mills what Mills attributed to him.6 Respondent’s counsel did not request a limiting instruction and none was given.7 The jury convicted respondent. On his appeal a divided panel of the Court of Appeals reversed. 707 F. 2d 1013 (1983).8
Whether evidence of a witness's and a party's common membership in a prison gang is admissible to show the witness's bias?9
The Federal Rules of Evidence permit impeachment by showing bias because a successful showing of bias tends to make the facts to which the witness testified less probable.10 Common membership in an organization is probative of bias even without proof that the witness has personally adopted its tenets.11
Yes. Ehle's testimony about the prison gang made the existence of Mills' bias towards respondent more probable.12 Mills had testified that Ehle planned to implicate respondent falsely after the robbery.13 Ehle testified that the tenets of the organization required members to lie to protect each other.14 This evidence supported the inference that Mills' testimony was slanted in respondent's favor due to their common membership.15
The evidence was properly admitted to show bias.16
Whether the district court abused its discretion under Federal Rule of Evidence 403 by admitting testimony describing the gang's tenets?17
No. The District Court carefully considered the arguments of counsel both in chambers and at the bench before admitting Ehle’s rebuttal testimony.20 To minimize prejudice the court prohibited use of the name Aryan Brotherhood.21 The court offered to give a limiting instruction and sustained objections to questions concerning punishment for violating the gang's rules.22 These measures ensured that the highly probative evidence of the gang's tenets did not unduly prejudice respondent.23
The district court did not abuse its discretion.24
Whether Rule 608(b) barred the admission of evidence concerning the witness's membership in the gang as extrinsic evidence of specific instances of conduct?25
Rule 608(b) prohibits the introduction of extrinsic evidence of specific instances of conduct to attack a witness's character for truthfulness.26 There is no rule of evidence which provides that testimony admissible for one purpose is inadmissible because it is inadmissible for another purpose.
No. The proffered testimony with respect to Mills’ membership in the Aryan Brotherhood sufficed to show potential bias in favor of respondent.2728 Because of the tenets of the organization described, it might also impeach his veracity directly.29 However, the evidence was admissible to show bias, and there is no rule that relevant evidence admissible for one purpose becomes inadmissible because it may also tend to show the witness is a liar.30
Rule 608(b) did not bar the admission of the evidence.31