Two brothers, Lamont B. Nelson (“L. Nelson”) and Delano C. Nelson (“D. Nelson”), committed various federal offenses related to the armed robbery of an Indianapolis jewelry store. D. Nelson was sentenced to 230 months imprisonment; L. Nelson was sentenced to 200 months imprisonment. The Nelsons did not actually rob the store: they recruited three young men to commit the robbery. The brothers gave the actual robbers guns, helped them steal a getaway ear, and instructed them how to carry out the robbery. From the approximately $500,000 in goods taken, the actual robbers each received a watch taken in the robbery and a couple hundred dollars. L. Nelson took a large diamond valued at $117,000. D. Nelson and two additional accomplices, Gregory Brown and Darry Herrington, took most of the rest of the jewelry.
All those involved in the robbery — except the Nelsons — pleaded guilty. At trial several people with knowledge of the crime testified against the Nelsons. The testimony of three of those witnesses is at issue in this appeal: (1) Darry Herrington, who had helped plan the robbery; (2) Virgil Terrell Douglas, an acquaintance who had seen the Nelsons acquire guns for the robbery; and (3) Viveca Traylor, who had been involved in the conspiracy to rob the jewelry store, and who was a friend and sometime girlfriend of D. Nelson. All three "witnesses gave extensive damaging testimony against the Nelsons.
During trial, the district court limited the defense’s cross-examination of Herring-ton, Douglas, and Traylor in two areas. The court prevented defense counsel from asking Herrington and Traylor what penalties they might have faced without plea-bargains. The court also prevented defense counsel from asking Herrington and Douglas about other robberies in which they were supposedly involved. 1
During cross-examination defense counsel impeached the credibility and motives of all three witnesses. They all had criminal pasts, which the jury heard about in detail. Both Herrington and Traylor testified under plea-bargains with the government. Douglas testified under a grant of immunity, under which the government agreed not to use his testimony against him in a federal prosecution. The jury heard about the existence of all these plea-bargains and about what the witnesses were to receive from the bargains.
A jury convicted both Nelsons of all the crimes with which they were charged. In sentencing D. Nelson, the district court added a two-level enhancement for obstructing justice, based on evidence that he had threatened witnesses before the trial.
The Nelsons now argue that the trial judge should not have limited cross-examination of Herrington, Douglas, and Traylor. D. Nelson also argues that the trial judge should not have enhanced his sentence for obstructing justice. We affirm the convictions and sentence.
ANALYSIS
1. Cross-Examination
The Nelsons argue that the district court erred in limiting their cross-examina *708 tions. Their first major argument is that the district court violated their Sixth Amendment rights of confrontation when it refused to allow them to cross-examine Herrington and Traylor about the penalties they faced without their plea-bargains. The Nelsons argue that, they needed to bring out those possible penalties to show that Herrington and Traylor were motivated to testify falsely.
While the Sixth Amendment guarantees a defendant the right to cross-examine witnesses, it allows a trial judge to place reasonable limits on the cross-examination.
United States v. Saunders,
In general, we review a trial judge’s limitations on the extent of cross-examination for an abuse of discretion.
United States v. Neely,
The Nelsons argue that the district court’s limitations of their cross-examinations of Herrington and Traylor infringed their core Sixth Amendment rights. The brothers argue in vain. Those limitations on cross-examination did not deny the defendants the opportunity to
establish
that the witnesses may have had a motive to lie; rather, the limitations denied them the opportunity to
add extra detail
to that motive. ‘“[T]he exposure of a witness’ motivation in testifying is a proper and important function of the constitutionally protected right of cross-examination.’ ”
Van Arsdall,
The jury heard evidence exposing Herrington’s and Traylor’s motive to lie. They heard exhaustive detail about Herring-ton’s and Traylor’s plea-bargains. The jury knew those plea bargains could have moved the witnesses to lie, to please the government so they might spend less .time in prison. The extensive testimony the jury heard was more than adequate. “ ‘[Wjhen reviewing the adequacy of a cross-examination, the question is whether the jury had sufficient information to make a discriminating appraisal of the witness’s motives and bias.’ ”
United States ex rel. Ashford v. Director, III. Dept. of Corr.,
*709
Several years ago we addressed and answered a question essentially identical to the question we decide today. In
United States v. Fitzgerald,
The Nelsons’ contention is indistinguishable from our decision in Fitzgerald. Grants of immunity from prosecution and plea bargains are both deals with the government under which the witness testifies on behalf of the government and gets benefits in return. Both immunity grants and plea bargains potentially give witnesses motives to testify falsely. In Fitzgerald, as here, the jury was made well aware of the witness’ bargain and was able to evaluate its impact on the witness’ credibility. Beyond that, it is within the discretion of the trial court to limit peripheral testimony about the bargains.
Furthermore, we note that the Ninth Circuit a few years ago reached the same conclusion on the question we face toddy. In
United States v. Dadanian,
The Nelsons make an argument tied to their first argument about the motives of witnesses to lie. They say that the district court improperly excluded cross-examination concerning other robberies Herrington and Douglas supposedly committed. The Nelsons admit that Herrington and Douglas had no bargains with the government regarding those robberies that might have motivated the witness to lie. Instead, they speculate that there was an implicit, unspoken bargain: the authorities ignored those crimes in return for Herrington’s and Douglas’ testimony against the Nelsons. They argue that evidence of other robberies would have shown that the witnesses might have had an additional motive to lie.
That argument falls flat. Evidence of other robberies would have been entirely peripheral to the defendants’ rights to confront witnesses. The jury knew all about Herring-ton’s real plea-bargain and about Douglas’ receipt of use immunity. Additional cross-examination on this topic would not have established a potential motive to lie but merely would have embellished facts already showing that motive.
Robinson,
The Nelsons’ second major argument is that they should have been allowed more opportunity to impeach Herrington’s and Douglas’ credibility, using evidence that they committed other armed robberies. We reject this argument as well. The general credibility of a witness is a matter collateral to the Sixth Amendment confrontation right.
Ashford,
The Federal Rules of Evidence also provide that evidence of a witness’ prior bad acts to impeach his credibility is largely a matter for the discretion of the trial court:
Specific instances of the conduct of a witness, for the purpose of attacking or supporting the witness’ credibility ... may not be proved by extrinsic evidence. They may, however, in the discretion of the court, if probative of truthfulness or untruthfulness, be inquired into on cross-examination of the witness (1) concerning the witness’ character for truthfulness or untruthfulness....
Fed.R.Evid. 608(b) (emphasis added). The trial judge explicitly exercised his discretion under 608(b). 2
The Nelsons overlook that Herrington’s and Douglas’ credibility was already severely damaged by testimony the district court did allow. Herrington admitted that he had been a conspirator in the Indianapolis robbery, that he had lied to police earlier about his involvement in the robbery, and that he had been a drug dealer. Douglas, who was only 17 years old when he testified, admitted to lying repeatedly to the police and the FBI, that he had been convicted three times of vehicle theft, and that he had been carrying a handgun when arrested. Any additional information suggesting that Herrington and Douglas were hardly model citizens would at most have had a marginal impact on the jury’s evaluation of their general credibility. Thus, the trial judge was again well within his discretion in his decision.
Even had the district court somehow erred in limiting the scope of cross-examination, the error was harmless. Harmless error analysis applies to errors arising under the Sixth Amendment confrontation clause.
Van Arsdall,
2. D. Nelson’s Sentence
We dispose quickly of D. Nelson’s groundless claim that the district court erred in calculating his sentence. At sentencing, the district court heard testimony that D. Nelson had made several threats against the lives and families of witnesses. The court found that the government had shown by a preponderance of the evidence that D. Nelson had obstructed justice and therefore gave him a two-level enhancement of his sentence. D. Nelson now claims that the judge erred in basing his conclusion on hearsay testimony.
To use evidence during sentencing, the judge must only decide that the evidence is reliable and must allow the defendant opportunity to rebut.
United States v. Nowicki,
In
Nowicki,
we explicitly held that in sentencing a defendant the judge could permissibly rely on hearsay evidence of threats.
D. Nelson was allowed to rebut the evidence that he had threatened witnesses who were to testify at his trial. He denied that he had made those threats; the judge, as was his prerogative, did not believe him. Nelson is not entitled to a belief in his rebuttal, just to the opportunity to present it.
The district court did not abuse its discretion when it determined that the evidence was reliable. There is no indication that the evidence of threats was false.
Escobar-Mejia,
In sum, the Nelsons’ appeal is without merit. Their convictions, and the sentence of D. Nelson, are AFFIRMED.
Notes
. The government made motions
in limine,
to prohibit cross-examination regarding these robberies. D. Nelson properly objected to both of the government's motions. L. Nelson, however, did not object to the government’s motion regarding Herrington's testimony; instead he made an identical motion, agreeing with the government that the evidence should be excluded. Therefore, absent plain error, L. Nelson has waived his right to appeal the trial court’s decision about Herrington’s testimony.
United States v. Maholias,
. We decline the government’s invitation to address the further question of whether, under 608(b), acts of armed robbeiy are probative of a witness' truthfulness or untruthfulness.
See Varhol v. National R.R. Passenger Corp.,
