United States Court of Appeals
                            FOR THE EIGHTH CIRCUIT
                                   ___________

                                   No. 08-1623
                                   ___________

United States of America,               *
                                        *
            Appellee,                   *
                                        * Appeal from the United States
      v.                                * District Court for the
                                        * Eastern District of Missouri.
Christopher Adam Walley,                *
                                        *
            Appellant.                  *
                                   ___________

                             Submitted: September 23, 2008
                                Filed: June 4, 2009
                                 ___________

Before BYE, BEAM, and COLLOTON, Circuit Judges.
                           ___________

COLLOTON, Circuit Judge.

       A jury convicted Christopher Adam Walley of conspiring to distribute five
grams or more of methamphetamine, and aiding and abetting the possession with the
intent to distribute five grams or more of methamphetamine. On appeal, Walley
challenges the jury selection process and argues that his Sixth Amendment right of
confrontation was violated when the district court1 limited his cross-examination of
two prosecution witnesses. We affirm.


      1
        The Honorable Jean C. Hamilton, United States District Judge for the Eastern
District of Missouri.
                                          I.

      In September 2005, Walley, Brandon Pender, and Tara Dewrock formed a
conspiracy to sell methamphetamine. Pender recently had returned from Las Vegas,
where he had discovered access to inexpensive methamphetamine, and Walley and
Dewrock knew people to whom they could sell the methamphetamine.

        According to evidence presented at trial, over the next few months, Walley and
Pender took a series of trips to Las Vegas to obtain methamphetamine. On the first
trip in October 2005, they were unable to obtain methamphetamine from Pender’s
planned source, but did obtain a small supply for their personal use. Walley and
Pender took a second trip to Las Vegas in December 2005 and brought back to
Missouri about 100 grams of methamphetamine. Walley drove on the trip and
provided security for the drug transaction. Walley and Dewrock then sold the
methamphetamine in Missouri and provided the proceeds to Pender. In February
2006, Dewrock was caught possessing methamphetamine and marijuana. She became
a confidential informant in an effort to avoid prosecution. Walley and Pender made
their third and final trip to Las Vegas to obtain methamphetamine in April 2006, with
Walley again driving and providing security.

      When Walley and Pender returned to Missouri to meet with Dewrock, they
were instead met by law enforcement officers, who had been alerted to the conspiracy
by Dewrock. The officers seized 19.2 grams of methamphetamine, a cutting agent,
and a set of hand scales from the vehicle, and arrested Walley and Pender. Once in
custody, Walley admitted that he knew the methamphetamine was in the vehicle, that
he had used some of it twice, that he knew it was going to be distributed in southeast
Missouri, and that he expected to be paid for his time driving to Las Vegas after the
methamphetamine was sold.




                                         -2-
        Walley was indicted for conspiracy to distribute five grams or more of
methamphetamine, in violation of 21 U.S.C. §§ 841(a)(1) and 846, and possession
with intent to distribute five grams or more of methamphetamine, in violation of 21
U.S.C. § 841(a)(1). After a two-day jury trial, at which both Pender and Dewrock
testified for the government, Walley was convicted of the conspiracy charge and of
aiding and abetting the possession with intent to distribute five grams or more of
methamphetamine. The district court sentenced Walley to 97 months’ imprisonment.

                                            II.

       Walley first argues that the district court erred in overruling his objection to the
government’s peremptory strike of an African-American prospective juror. At the
close of the jury selection process, Walley objected to the government’s strike of the
juror, pointing out that she was the only African-American on the panel, that Walley
was African-American, and that Walley was concerned about receiving a fair trial
without any African-American jurors. In response to Walley’s objection, the
government explained that it exercised the strike based on three factors: the
prospective juror’s back problem, her dental abscess, and the fact that she knew a
friend or family member with substance-abuse issues. The government elaborated that
it was concerned that the prospective juror’s health issues would prevent her from
being a careful and attentive juror. The district court found that the prospective
juror’s back problem was not a valid basis for the government’s peremptory strike, but
nevertheless determined that the juror’s abscess and connection to a person with
substance-abuse issues were sufficient reasons to justify the strike. We review the
district court’s denial of Walley’s objection for clear error. United States v. Wilcox,

, 1169 (8th Cir. 2007).

      A party may not use peremptory strikes to exclude prospective jurors
deliberately on account of their race. See Batson v. Kentucky, 

, 96-98
(1986). When a defendant raises an objection to the government’s use of a

                                           -3-
peremptory strike under Batson, the district court should engage in a three-step
inquiry to determine whether the strike was based on the prospective juror’s race.
First, the court must determine whether the defendant has made a prima facie showing
of racial discrimination. If the defendant does so, then the burden shifts to the
government to present a race-neutral explanation for the strike. If the government
provides such a reason, the burden shifts back to the defendant, and the court must
determine whether the defendant ultimately has proven that the government’s strike
was based on race. See Smulls v. Roper, 

, 859 (8th Cir. 2008) (en banc).

       In this case, the district court did not expressly determine whether Walley made
a prima facie showing of discrimination. When asked by the court to respond to
Walley’s objection, the government stated that it had “a reason for striking [the
prospective juror] that had nothing to do with her perceived ethnicity.” T. Tr. Vol. I,
at 82. The district court then “cut to the chase” and requested the government’s
reasoning. Though it is doubtful that Walley made a prima facie showing of
discrimination, given that his sole argument was that the prospective juror was the
only African-American on the panel, see United States v. Roebke, 

, 913
(8th Cir. 2003) (stating that a strike of the only African-American prospective juror
was insufficient alone to make a prima facie showing), the government did not contest
the issue and instead responded with a statement about its reasoning. Our cases state
(though arguably do not hold) that once the government responded with a race-neutral
explanation and the district court ruled on the ultimate question of purposeful
discrimination, the preliminary prima facie issue became moot. See id.; United States
v. Brooks, 

, 840-41 (8th Cir. 1993) (quoting Hernandez v. New York, 

, 359 (1991) (plurality opinion)). But see United States v. Stewart, 

, 924 (11th Cir. 1995). Therefore, we focus on the district court’s determination
that the government offered a sufficient race-neutral explanation to show that it did
not purposefully discriminate against the prospective juror on account of her race.
The district court found that two of the government’s explanations for the strike – the
juror’s dental abscess and her connection to a person with substance-abuse issues –

                                         -4-
were sufficient to justify the government’s peremptory strike. Both of these reasons
are race-neutral.

       On appeal, Walley argues for the first time that the government’s failure to
strike other similarly situated non-black jurors demonstrates that the government’s
explanation for its strike was pretext. Our cases hold, however, that we will not
consider claims of pretext based upon the failure to strike similarly situated jurors
unless the point was raised in the district court. See United States v. Hunt, 

, 1012 (8th Cir. 2004); United States v. Boyd, 

, 1078 (8th Cir.
1999); United States v. Gibson, 

, 1232-33 (8th Cir. 1997). The
Supreme Court in Snyder v. Louisiana, 

(2008), did analyze similarly
situated jurors even though the issue was not raised in a state trial court, 

12, but the court noted that the state supreme court did not hold that the petitioner had
procedurally defaulted an argument based on comparable jurors. 

n.2. Our
precedent in such decisions as Hunt, Boyd, and Gibson applies the sort of procedural
bar that was absent in Snyder, and the rule is applicable here. Walley did not raise a
claim about similarly situated prospective jurors at trial, and we therefore do not
consider the issue on appeal. Walley’s claim based on Batson is without merit.

                                          III.

     Walley next contends that the district court violated his rights under the Sixth
Amendment by limiting his cross-examination of prosecution witnesses Brandon
Pender and Tara Dewrock. We disagree.

       The Sixth Amendment provides a criminal defendant the right “to be confronted
with the witnesses against him.” The primary purpose of this right is to guarantee the
opportunity for effective cross-examination, particularly with respect to a witness’s
potential bias. Delaware v. Van Arsdall, 

, 679 (1986). “The
Confrontation Clause is not, however, without limit; courts ‘retain wide latitude

                                          -5-
insofar as the Confrontation Clause is concerned to impose reasonable limits on such
cross-examination based on concerns about, among other things, harassment,
prejudice, confusion of the issues, the witness’ safety, or interrogation that is
repetitive or only marginally relevant.’” United States v. Beckman, 

, 524
(8th Cir. 2000) (quoting Van 

). A limitation on cross-
examination does not violate the Sixth Amendment unless the defendant shows that
“[a] reasonable jury might have received a significantly different impression of [the
witness’s] credibility had [defense] counsel been permitted to pursue his proposed line
of cross-examination.” Van 

.

                                          A.

         Walley first argues that his right to confront Pender was violated when the
district court prevented him from cross-examining Pender about the specific possible
lengths of the sentence he was facing. Pender testified extensively on direct
examination about the formation and operation of the drug conspiracy between
Walley, Dewrock, and Pender. He also admitted that he was awaiting sentencing on
the charge of conspiracy to distribute methamphetamine, was testifying pursuant to
a plea agreement, and hoped to get a reduction in his sentence because of his
testimony in Walley’s trial. He further explained his understanding that he would
receive a reduction only if the government exercised its discretion to move for the
reduction and that the judge ultimately would determine the extent of any reduction.

      On cross-examination, Walley’s counsel sought to ask Pender about the forty-
year maximum sentence for Pender’s offense, and the government objected. During
the ensuing bench conference, Walley’s counsel also sought permission to inquire
about the five-year mandatory minimum sentence. He argued that this information
was relevant to Pender’s credibility, because Pender could be sentenced below this
minimum sentence only if the government made a substantial-assistance motion. See
18 U.S.C. § 3553(e). The government argued that the questioning was an

                                         -6-
impermissible attempt to present, indirectly, details about Walley’s possible sentence,
because Walley and Pender were charged with the same offense. See United States
v. Thomas, 

, 1200 (8th Cir. 1990) (“To inform a federal jury about a
defendant’s punishment would only introduce improper and confusing considerations
before it.”). The district court sustained the objection, finding that the specifics of the
sentence were not relevant, that any probative value was outweighed by their
prejudicial effect, and that Pender’s credibility could be examined sufficiently by
discussing his desire that the government move for a reduced sentence because of his
testimony. The district court, however, did permit Walley’s counsel to elicit from
Pender that “there’s certainly no disagreement that you’re facing the possibility of a
significant sentence in this case, is that correct?” T. Tr. Vol. II, at 66 (emphasis
added).

       Walley relies on United States v. Caldwell, 

(8th Cir. 1996), and
United States v. Roan Eagle, 

(8th Cir. 1989), for the proposition that the
district court erred by excluding evidence of the specific minimum sentence that
Pender faced without a substantial-assistance motion by the government. Caldwell
and Roan Eagle both held that it was error for a district court to limit cross-
examination about the sentence of a cooperating witness, but the circumstances
differed from this case. In Roan Eagle, the witness already had received the benefit
of a reduction in charges. In exchange for the witness’s cooperation, the prosecution
had agreed to forego a charge that carried a possible life sentence, and to accept a
guilty plea to an offense with a maximum term of ten years’ imprisonment. The court
held that it was error to preclude the defense from presenting evidence of the
reduction in maximum penalties that the witness already had received. Roan 

. Similarly, in Caldwell, the prosecution had agreed to dismiss a
conspiracy charge with a maximum penalty of ten years’ imprisonment and to allow
a cooperating witness to plead guilty to a misdemeanor with a maximum sentence of
one year. The court held that it was insufficient to permit the defense to elicit only
that the witness originally faced the potential of “time in the penitentiary” before the

                                           -7-
reduction in charges. 

; see also United States v. Chandler,

, 221-22 (3d Cir. 2003).

       In this case, Walley does not argue that Pender received a reduction in the range
of possible imprisonment before he testified. Rather, Pender hoped to receive a
motion by the government to reduce his sentence after the trial. There is no proffered
evidence that Pender expected to receive a specific reduction, but Walley argues that
he should have been permitted to elicit that Pender faced a minimum of five years’
imprisonment if the government did not move to reduce the sentence. He contends
that the minimum sentence is relevant to bias, because the greater the mandatory
minimum, the stronger the incentive for the witness to earn a reduction. See United
States v. Larson, 

, 1106 (9th Cir. 2007) (en banc); United States v.
Cropp, 

, 359 (4th Cir. 1997).

       It is not self-evident that a witness facing a longer mandatory minimum has a
greater desire to please the government; the witness’s motivation likely depends on
the magnitude of the benefit that he expects to receive for cooperating. A fifty-year-
old witness subject to mandatory life imprisonment may think a reduction to thirty-
eight years is worth little, while a twenty-five-year-old facing five years would be
eager to reduce the term to four. See 

(Graber, J.,
concurring in part). Our decisions in Roan Eagle and Caldwell, therefore, emphasized
that the accused should have been able to contrast the original punishment faced by
the witness with the more lenient punishment contemplated by the plea agreement –
not merely that the original punishment alone was evidence of bias. Here, there is no
offer of proof that Pender expected that a particular benefit would flow from his
cooperation. The testimony showed only that Pender hoped through his assistance to
reduce by an undefined degree the sentence that he otherwise faced.

      We are not persuaded that evidence of Pender facing a “five-year sentence”
rather than a “significant sentence” would have given the jury a “significantly

                                          -8-
different impression” of Pender’s credibility. Van 

. The jury
was aware that Pender was subject to a significant sentence, and that the court could
reduce the sentence only upon motion of the government. Walley complains that the
jury might have thought Pender’s “significant sentence” was only two years, rather
than five. It seems just as likely, however, that the jury thought “significant” meant
that Pender and Walley faced a possible term of ten years or twenty. (Indeed, the
malleability of the term makes us wonder why the government thought it an
improvement over the actual mandatory minimum.) And even if the jury thought the
sentence, without reduction, would be two years, it does not follow that the jury would
have appraised Pender’s credibility more favorably when the record does not show the
extent of reduction that the witness expected. For example, if the amount of expected
reduction were held constant, which witness would appear more biased to the jury –
the witness hoping to reduce a sentence from two years to probation, or a witness
hoping to reduce a sentence from five years to three? In sum, we do not think that
whatever marginal value might have been derived from presenting evidence that
Pender faced a specific minimum sentence of five years is sufficient on this record to
demonstrate that the court’s ruling violated Walley’s rights under the Confrontation
Clause. See United States v. Arocho, 

, 636 (7th Cir. 2002), abrogated
on other grounds by United States v. Rodriguez-Cardenas, 

, 960 (7th Cir.
2004); 

(“The appellants . . . have been unable to explain why
questions about exact sentences feared and sentences hoped for were necessary when
the jury was already well aware that the witnesses were cooperators facing severe
penalties if they did not provide the government with incriminating information.”);
United States v. Luciano-Mosquera, 

, 1153 (1st Cir. 1995).

                                          B.

      Walley also argues that the district court erred under the Confrontation Clause
by preventing him from cross-examining Dewrock about her drug trafficking activities
before the formation of the charged drug conspiracy. Like Pender, Dewrock testified

                                         -9-
about the formation and operation of the drug conspiracy. She also testified about her
efforts as a confidential informant that led to the arrests of Pender and Walley. She
admitted on direct examination that she had been a drug user for several years, and
that in return for her cooperation, the prosecuting authorities agreed to refrain from
bringing charges for violations of state or federal law.

       On cross-examination, Walley’s counsel elicited renewed admissions that
Dewrock was involved in a conspiracy to distribute methamphetamine, and that she
had distributed methamphetamine on multiple occasions. He then asked Dewrock the
following question: “During the periods in which you were using significant
quantities of methamphetamine over a four-year period and you were not, as you
allege here, obtaining anything from Mr. Pender or Mr. Walley, you distributed other
significant quantities of methamphetamine, did you not?” T. Tr. Vol. II, at 190. The
government objected on the ground that the question attempted impermissibly to
impeach Dewrock with prior bad acts. In response to the objection, Walley’s counsel
argued at a bench conference that the question was relevant to show that Dewrock was
“minimizing her involvement” in the conspiracy. The district court sustained the
objection, saying that Dewrock had admitted her role in the conspiracy and that
defense counsel had “an awful lot to argue to the jury on that,” but that the proposed
line of inquiry was not relevant.

       Dewrock’s prior distribution of methamphetamine was not admissible for the
purpose of attacking her character for truthfulness, United States v. Turner, 

, 223 (8th Cir. 1997); Fed. R. Evid. 608(b), and Walley did not state at the bench
conference a proper basis for admitting the evidence. On appeal, however, Walley
contends that Dewrock’s answer to the question should have been admitted to show
bias, because it was relevant to establish the full extent of the possible criminal
charges that Dewrock avoided by cooperating against Walley. We agree that evidence
of additional criminal conduct covered by a non-prosecution agreement is relevant to
show bias of the witness, but Walley forfeited this point by not explaining his

                                        -10-
rationale to the district court when offered the opportunity, so we review only for
plain error. See United States v. Purkey, 

, 757 (8th Cir. 2005); 

.

       Although Dewrock’s answer could have been relevant on the question of bias,
Walley fails to establish that the limitation on his questioning of Dewrock constituted
a plain error under the Sixth Amendment, or that there was a violation of the
Confrontation Clause at all. To show such a violation, Walley must demonstrate that
the excluded testimony might have given the jury a “significantly different
impression” of Dewrock’s credibility. Van 

. Dewrock
already had admitted that she was an active participant in Walley’s drug conspiracy,
that she repeatedly used and sold drugs, and that she was avoiding all federal and state
criminal prosecutions by cooperating. The jury thus had ample reason to conclude
that Dewrock had a strong motivation to assist the government, and evidence of
additional drug distributions for which Dewrock received immunity is unlikely to
have changed the jury’s impression of her credibility. See 

.
The district court’s limitation on Walley’s cross-examination of Dewrock thus affords
no basis for setting aside the conviction.

                                   *       *       *

      The judgment of the district court is affirmed.
                     ______________________________




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