United States Court of Appeals
                            FOR THE EIGHTH CIRCUIT
                                  ___________

                                  No. 04-1337
                                  ___________

United States of America,              *
                                       *
            Appellee,                  *
                                       * Appeal from the United States
      v.                               * District Court for the
                                       * Western District of Missouri.
Wesley Ira Purkey,                     *
                                       *
            Appellant.                 *
                                  ___________

                             Submitted: June 23, 2005
                                Filed: November 7, 2005
                                 ___________

Before ARNOLD, McMILLIAN, and COLLOTON, Circuit Judges.
                           ___________

ARNOLD, Circuit Judge.

      A jury convicted Wesley Purkey of the kidnapping, rape, and murder of
Jennifer Long, and sentenced him to death. See 18 U.S.C. §§ 1201(a), (g), 3559(d),
3591-3598. On appeal, Mr. Purkey raises myriad challenges to his conviction and
sentence. After careful review, we conclude that his arguments lack merit and
therefore affirm the judgment of the district court.1




      1
      The Honorable Fernando J. Gaitan, Jr., United States District Judge for the
Western District of Missouri.
       Jennifer Long, a sixteen year-old high school sophomore, disappeared in
January of 1998. On December 15, 1998, while in the Wyandotte County Jail
awaiting a Kansas state prosecution for the murder of eighty-year-old Mary Ruth
Bales, Mr. Purkey contacted Detective Bill Howard of the Kansas City, Kansas, Police
Department and offered to speak with him about a kidnapping and homicide that had
occurred earlier that year. Mr. Purkey told Detective Howard that he also wanted to
speak with an FBI agent about this crime because he wanted to spend his time in a
federal, rather than a state, institution. Detective Howard asked FBI Special Agent
Dirk Tarpley to go with him to meet with Mr. Purkey.

       The next day, Mr. Purkey met with Detective Howard and Agent Tarpley. At
the beginning of the meeting, Mr. Purkey executed a form indicating that he
understood and voluntarily waived his constitutional rights. He then told the officers
that he was going to plead guilty in the Kansas case and was therefore willing to
confess to the kidnapping, rape, and murder of a Missouri woman, provided that he
could serve his state time in a federal penitentiary. Detective Howard and Agent
Tarpley informed Mr. Purkey that they could not make any promises but would take
whatever he had to say to the United States Attorney. After giving an account of the
kidnapping, rape, and murder of the victim (who was later identified as Ms. Long),
Mr. Purkey refused to cooperate further unless he received assurances from the United
States Attorney that his case would be federally prosecuted.

       That afternoon, Detective Howard and Agent Tarpley met with Kurt Shernuk,
an Assistant United States Attorney for the District of Kansas. Although he was
skeptical of Mr. Purkey, Mr. Shernuk indicated that his office might be willing to
prosecute the case if Mr. Purkey fully cooperated with the investigators and provided
the location of the victim's remains and other evidence to corroborate his confession.

      After meeting with Mr. Shernuk, Detective Howard and Agent Tarpley returned
to the Wyandotte County Jail to speak with Mr. Purkey. They told him that

                                         -2-
Mr. Shernuk wanted a body and would require full cooperation, but they did not make
Mr. Purkey any promises as to the sentence that he might receive. Mr. Purkey then
led Messrs. Tarpley and Howard to the crime scene and to the place where he claimed
to have discarded the victim's undergarments and jaw bone. He told the officers that
because he had taken extraordinary measures to dispose of the body, including
dismembering it with a chain saw and burning the remains, the victim's remains were
not recoverable.

      More meetings occurred over the next several days. On December 17,
Detective Howard and Agent Tarpley again met with Mr. Purkey and, after being
reminded verbally of his constitutional rights, Mr. Purkey gave a detailed handwritten
confession. The next day, Detective Howard met with Mr. Purkey and, after
reminding him of his rights, conducted a photo lineup to see if he could identify the
victim. Without hesitation, Mr. Purkey identified Ms. Long. Agent Tarpley met with
Mr. Purkey three days later, and after being advised of his rights, Mr. Purkey
confessed again.

       During the guilt phase of his federal trial, Mr. Purkey affirmed his statements
about the killing and dismemberment of Ms. Long, but he disavowed his previous
statements that he forced Ms. Long to travel with him from Missouri to his home in
Kansas. Instead, he stated that Ms. Long, who he said he thought was a prostitute,
voluntarily entered his truck and accompanied him to his home. He indicated that he
fabricated the kidnapping aspect of the confession to ensure that his actions would be
considered, and therefore prosecuted as, a federal crime. After deliberating briefly,
the jury returned a verdict of guilty.

       During the penalty phase of the trial, the defense submitted and the court
instructed on twenty-seven mitigating factors. Mr. Purkey's primary mitigation
defense consisted of expert testimony indicating that he suffered brain damage that
resulted in diminished mental capacity. The government presented expert testimony

                                         -3-
to rebut this assertion and also produced evidence in support of six statutory and four
non-statutory aggravating factors.

        After deliberating for eleven hours and ten minutes, the jury found the existence
of all six of the statutory aggravating factors: (1) that the death of Ms. Long occurred
during the commission and attempted commission of her kidnapping; (2) that
Mr. Purkey killed Ms. Long in an especially heinous, cruel, and depraved manner in
that the killing involved torture and serious physical abuse; (3) that the victim was
particularly vulnerable due to her youthful age of sixteen years; (4) that Mr. Purkey
had previously been convicted of an offense punishable by a term of imprisonment of
more than one year, involving the use, attempted use, and threatened use of a firearm
against another person; (5) that Mr. Purkey had previously been convicted of an
offense resulting in the death of a person for which a sentence of life imprisonment
was authorized by statute; and (6) that Mr. Purkey had previously been convicted of
two or more offenses punishable by a term of imprisonment of more than one year,
committed on different occasions and involving the infliction and attempted infliction
of serious bodily injury and death upon another person. The jury also found the
existence of three of the four non-statutory aggravating factors: (1) that the
government established loss and harm because of the victim's personal characteristics
as an individual human being and the impact of the death upon the victim's family; (2)
that the defendant had previously killed Mary Ruth Bales in a vicious manner in that
he repeatedly struck her in the head with a hammer until she died; and (3) that
Mr. Purkey had a substantial criminal history. The jury did not record any evidence
of its findings with regard to the mitigating factors. It then determined that
Mr. Purkey should be sentenced to death.

                                       I.
       We begin with Mr. Purkey's arguments pertaining to the district court's denials
of his pretrial motions.



                                          -4-
                                           A.
       Mr. Purkey's primary argument on appeal is that the district court erred in
denying his motion to suppress his multiple confessions to the kidnapping, rape, and
murder of Ms. Long. He argues that the district court should have suppressed his
statements to Messrs. Tarpley and Howard because the statements were involuntary
and therefore obtained in violation of the fifth amendment to the Constitution. He
bases this argument on his assertion that the officers obtained the confessions through
a false promise, cf. United States v. Pierce, 

, 812-13 (8th Cir. 1998),
namely, that if he cooperated with the government he would receive a life sentence in
a federal institution. As an alternative to suppression, Mr. Purkey moved to prohibit
the government from pursuing the death penalty. The district court also denied that
motion.

       The core of Mr. Purkey's argument is that Detective Howard and Agent Tarpley
procured his confession by indicating that the Assistant United States Attorney had
accepted Mr. Purkey's alleged quid pro quo offer, that is, that Mr. Purkey would
confess to the crime and provide full cooperation in return for a life sentence in a
federal institution. Detective Howard and Agent Tarpley testified at the suppression
hearing that they never made this representation to Mr. Purkey. The district court,
adopting the discussion and conclusions in the report and recommendation of a
magistrate judge,2 squarely rejected Mr. Purkey's version of the events. It found that,
"[d]uring all of the time the officers spent with Purkey on December 16, 1998, there
were no hints or suggestions made to Purkey ... that Purkey would get a life sentence
if he confessed. No one told Purkey that a life sentence would be recommended if he
confessed." The court inserted a footnote within this language to make explicit that
it found "the testimony of Special Agent Tarpley and Detective Howard more credible
than that of defendant Purkey" on the issue of whether Messrs. Tarpley and Howard


      2
        The Honorable Sarah W. Hays, United States Magistrate Judge for the Western
District of Missouri.
                                         -5-
told Mr. Purkey that the Assistant United States Attorney had agreed to give
Mr. Purkey a life sentence in the federal system in exchange for a full confession.
Finally, the court concluded that during the course of the investigation, "[n]o promises
were made to defendant Purkey in exchange for his confessions. While the defendant
was apparently surprised to find out that the death penalty was a potential sentence he
might receive, the officers did not mislead [the] defendant into believing that there
was no federal death penalty."

       Because Mr. Purkey's challenges are to the district court's conclusions regarding
the facts underlying its decisions to deny his motions, we review the matter for clear
error. See United States v. Kilgore, 

, 353 (8th Cir. 1995); see also United
States v. Heath, 

, 1275 (8th Cir. 1995), cert. denied, 

(1995).
After a thorough review of the record, we cannot conclude that the district court
clearly erred in arriving at the credibility determinations and factual conclusions that
it reached. We therefore affirm the district court's denial of Mr. Purkey's motion to
suppress his statements and his motion to prohibit the government from seeking the
death penalty.

                                          B.
       Mr. Purkey also maintains that the district court erred when it denied his motion
to dismiss based on the alleged destruction of notes that Mr. Purkey asserts that he
took to document his conversations with Detective Howard and Agent Tarpley in
December of 1998. Mr. Purkey testified that these notes were destroyed by prison
staff during a "shakedown" of his segregation pod while he was incarcerated at
CCA(Corrections Corporation of America)-Leavenworth. He asserts that the
destruction of these notes constitutes a denial of due process and requires dismissal
of the indictment.

      In United States v. Malbrough, 

(8th Cir. 1990), cert. denied,

(1991), we recognized that the "Supreme Court has held that the state's

                                          -6-
failure to preserve evidence does not constitute a denial of due process unless ...
comparable exculpatory evidence was not reasonably available to the defendant." 

(citing California v. Trombetta, 

, 488-89 (1984)). The district
court, adopting the discussion and conclusions of the magistrate judge, concluded that
Mr. Purkey's motion must fail because, among other shortcomings, Mr. Purkey could
not demonstrate that he was unable to obtain comparable exculpatory evidence by
other means. We review the matter to determine whether this conclusion was clearly
erroneous, cf. United States v. Weise, 

, 504 (8th Cir. 1996), and we
conclude that it was not.

         At best, these notes can be characterized as Mr. Purkey's account of his
conversations with Detective Howard and Agent Tarpley. They were neither
transcripts of the conversations nor were they attested to by Messrs. Howard or
Tarpley. They were simply Mr. Purkey's recollections of the conversations as
recorded shortly after each conversation concluded. Mr. Purkey had ample
opportunity to introduce comparable evidence in the form of his own testimony as to
the substance of the conversations. And, although these notes could have been read
into evidence to fill gaps in Mr. Purkey's recollection as to the content of those
conversations, see Fed. R. Evid. 803(5), Mr. Purkey's own testimony belied his
assertion of an incomplete recollection of the conversations. We can find no clear
error in the magistrate judge's observation that, "Despite Purkey's contention that he
needs these notes to assist him with remembering the details of the interrogations,
Purkey's testimony would suggest that he has no trouble remembering [those] details
... (at least until defense counsel reminded him that he should not remember)." Hence
the district court did not err in denying Mr. Purkey's motion to dismiss based on the
alleged destruction of his notes.

                                         C.
     Mr. Purkey also argues that the district court erred in denying his pretrial
motion asking the court to prohibit the government from seeking the death penalty

                                         -7-
because of two violations of the fifth amendment's indictment clause. First,
Mr. Purkey asserts that the Federal Death Penalty Act (FDPA), 18 U.S.C. § 3591-
3598, is facially unconstitutional because it vests the prosecution with unilateral
authority to seek the death penalty without ever taking the matter of whether the death
penalty is justified to the grand jury, see 18 U.S.C. § 3593(a). Second, he argues that
his prosecution ran afoul of the indictment clause because the government failed to
seek an indictment upon some of the necessary elements of the capital prosecution,
namely, the government's non-statutory aggravating factors and the issue of whether
the aggravating factors sufficiently outweighed any mitigating factors to justify a
sentence of death. Both of these are questions of law, and we therefore review them
de novo. See United States v. Koons, 

, 990 (8th Cir. 2002); cf. United
States v. Roy, 

, 491 (8th Cir. 2005).

       In United States v. Allen, 

, 949 (8th Cir. 2005) (en banc), we
addressed the same facial challenge that Mr. Purkey now presents. There we
recognized that the FDPA does vest the prosecution with authority to charge
aggravating factors in a notice of intent to seek the death penalty, and does not
specifically require the government to bring those factors before the grand jury for
inclusion in the indictment. But because "nothing in the Act precludes the
government from also submitting them to the grand jury for inclusion in the
indictment," we rejected the contention that the FDPA was unconstitutional. 

Purkey's facial challenge also fails.

       To deal with Mr. Purkey's second challenge, we begin with a bit of background.
Under the FDPA, once the jury finds the defendant guilty of one of the offenses listed
in 18 U.S.C. § 3591, the trial proceeds to a separate phase – the sentencing or penalty
phase. In a homicide case, the jury must make three determinations in this latter phase
before it can impose the death penalty: First it must find, unanimously and beyond
a reasonable doubt, that the defendant acted with the requisite mens rea. See
18 U.S.C. § 3591(a)(2). Second, again unanimously and beyond a reasonable doubt,

                                         -8-
it must find the existence of at least one statutory aggravating factor. See 18 U.S.C.
§§ 3592(c), 3593(d). If the above two requirements are satisfied, the jury must then
determine whether the aggravating factors, both statutory and non-statutory,
"sufficiently outweigh" the mitigating factors presented by the defendant to justify a
death sentence, "or, in the absence of a mitigating factor, whether the aggravating
factor or factors alone are sufficient to justify" that sentence. See 18 U.S.C. § 3593(e).

       Mr. Purkey maintains that because the jury is required to take this third step
before it may impose a sentence of death, the necessary elements for a capital
prosecution under the FDPA include all aggravating factors, including non-statutory
aggravating factors, and the weighing of aggravating factors versus mitigating factors.
He therefore contends that because his superseding indictment did not include non-
statutory aggravating factors or a determination that there exists probable cause to
believe that aggravating factors sufficiently outweigh mitigating factors so as to
justify a sentence of death, it falls short of what the fifth amendment requires. We
disagree.

       "[T]he same facts that the Sixth Amendment requires to be proven to the petit
jury beyond a reasonable doubt in state and federal prosecutions must also be found
by the grand jury and charged in the indictment in federal prosecutions." 

. For that reason, Allen held that to comport with the fifth amendment
"at least one statutory aggravating factor and the mens rea requirement [must] be
found by the grand jury and charged in the indictment" in a prosecution under the
FDPA. 

superseding indictment satisfies both of these requirements.

       The indictment must charge at least one of the statutory aggravating factors that
is ultimately found by the petit jury because "that is what is required to elevate the
available statutory maximum sentence from life imprisonment to death." 

words, including that factor in the indictment is required to make the defendant
eligible for the death penalty. See United States v. Higgs, 

, 299 (4th Cir.

                                           -9-
2003), cert. denied, 

(2004). We now make clear what Allen merely
implied: "There is no requirement that the indictment allege all of the factors that
might be weighed by the jury when deciding whether to impose a death sentence."

. Non-statutory aggravating factors do not increase the
maximum punishment to which a defendant is subject. They are neither sufficient nor
necessary under the FDPA for a sentence of death. Their purpose is merely to aid the
sentencer "in selecting the appropriate sentence from the available options," 

" 'on the basis of the character of the [defendant] and the circumstances of the crime,'
" 

v. California, 

, 972 (1994)).

        Further, it makes no sense to speak of the weighing process mandated by
18 U.S.C. § 3593(e) as an elemental fact for which a grand jury must find probable
cause. In the words of the statute, it is a "consideration," 18 U.S.C. § 3593(e), – that
is, the lens through which the jury must focus the facts that it has found to produce an
individualized determination regarding "whether the defendant should be sentenced
to death, to life imprisonment without possibility of release or some other lesser
sentence." 

conclude that Mr. Purkey's arguments based on the indictment clause
of the fifth amendment are without merit.

                                            II.
        Mr. Purkey next challenges the district court's for-cause exclusion of three
potential jurors who expressed reluctance to impose the death penalty. In Wainwright
v. Witt, 

, 420, 424 (1985), the Supreme Court instructed that a potential
juror may be excluded for cause based on his or her views on capital punishment only
if those views would " ' prevent or substantially impair the performance of his duties
as a juror in accordance with his instructions and his oath. ' " (quoting Adams v. Texas,

, 45 (1980)). We review a district court's removal of death-scrupled
venirepersons for an abuse of discretion. See United States v. Nelson, 

,
710-11 (8th Cir. 2003), cert. denied, 

(2004); United States v. Ortiz,
                                          -10-


, 888 (8th Cir. 2002), cert. denied, 

& 

(2003).

       Mr. Purkey first asks us to find error in the district court's removal of Margaret
Fox. He begins by inviting us to adopt the holding of the Tenth Circuit in United
States v. Chanthadara, 

, 1270 (10th Cir. 2000), cert. denied, 

(2001), and review Ms. Fox's removal de novo because the court struck her solely
on the basis of her answers to a questionnaire. We do not agree, however, with
Chanthadara's implicit assumption that a district court's decision on the qualifications
of a juror is entitled to deference only because of that court's superior position to
assess a potential juror's demeanor and credibility. See 

Other reasons,
such as respect for the trial process, "the expertise developed by trial judges," and the
desire to conserve judicial resources also underpin the fundamental principle that
"appellate courts are not to decide factual questions de novo, reversing any findings
they would have made differently." Maine v. Taylor, 

, 145 (1986); cf.
Anderson v. Bessemer City, 

, 574-76 (1985); Fed. R. Civ. P. 52(a).
Accordingly, we decline this invitation to stray from the standard of review
established in our previous cases, which is whether the district court abused its
discretion.

       The district court did not abuse its discretion by striking Ms. Fox. She
repeatedly indicated on the questionnaire that she had serious reservations about
capital punishment. When asked in question thirty-eight of the questionnaire to
describe her feelings about the death penalty, how strong those feelings were, and how
long she had held them, she wrote, "Within the last 50 years I've gained stronger and
stronger feelings against [the] use of the death penalty. I believe major criminals
should be punished, but taking away their lives should be left to God." Her responses
to questions thirty-six and thirty-seven, which asked about the effect that exposure to
books, articles, and movies about the death penalty had on her, also indicate that she



                                          -11-
"questioned that the death penalty should be used" and "question[ed] the right of the
courts to administer the death penalty."

      Question thirty-nine, a multiple choice question, gave each juror an opportunity
to mark the choice that best described his or her feelings about the death penalty.
Three of the eight choices pertained to people with some degree of opposition to the
death penalty. They were as follows:

             a. I am opposed to the death penalty, and I will never vote
             to impose the death penalty in any case, no matter what the
             facts.

             b. I am opposed to the death penalty, and I would have a
             difficult time voting to impose the death penalty.

             c. I am opposed to the death penalty, but could vote to
             impose the death penalty if I believed that the death penalty
             was called for in light of the facts and law in the case.

Ms. Fox declined to indicate that she could vote to impose the death penalty by
selecting choice "c" and instead chose the ambiguous "b." When we consider this
response together with her other answers regarding her views on the death penalty, we
find sufficient evidence in the record from which the district court could conclude that
her views on the death penalty would " 'substantially impair the performance of her
duties as a juror in accordance with h[er] instructions and h[er] oath.' " 

(quoting 

).

      Mr. Purkey also argues that the court erroneously struck Willie Randle after
mishearing or incorrectly recollecting his responses during voir dire. During voir dire,
the government asked Mr. Randle whether he would "hold the government to a higher

                                         -12-
burden of proof than what is required under the law." He responded, "I think I
would." When the government next asked whether he would hold it to a higher
burden of proof than "beyond a reasonable doubt" he replied, "It has to be proof
without a reasonable doubt." Later, in granting the government's request to strike
Mr. Randle, the district judge declared, "My recollection is that he's holding the
government to a higher standard than the law provides."

        Reviewing the cold record, it is difficult to divine exactly what Mr. Randle
meant when he replied that "[i]t has to be proof without a reasonable doubt." Although
those words of the transcript, taken literally, may indicate that Mr. Randle had agreed
to apply a burden equivalent to the one that the law actually imposes, the transcript
cannot provide any insight regarding Mr. Randle's intent in using the phrase "without
a reasonable doubt" instead of "beyond a reasonable doubt." This is why the Supreme
Court instructed in 

, that "deference must be paid to the
trial judge who sees and hears the juror." The trial judge, who had the opportunity to
observe the exchange, could have reasonably interpreted Mr. Randle's refusal to parrot
the words of the government and instead use the phrase "without a reasonable doubt"
as an affirmation of his earlier statement that he would hold the government to a
higher burden of proof than the law provides. Based on the colloquy between Mr.
Randle and the government, as well as the court's stated reason for its ruling, we
conclude that the district court did not abuse its discretion by striking this potential
juror.

       Finally, Mr. Purkey argues that the district court erred when it removed Gary
Danford for cause after he had been "rehabilitated." When questioned by the
government, Mr. Danford insisted that he would hold the government to a higher
burden of proof than reasonable doubt. But Mr. Danford reversed course under
subsequent questioning by Mr. Purkey's counsel and indicated that he would "follow
the law." The district court concluded that, "I think he has kind of made up his mind
what the standard is and that the standard he has decided upon is something different

                                         -13-
than what the law provides." Quite simply, the district court made a reasonable
judgment based on its impression of Mr. Danford's credibility as was its prerogative.
See 

; United States v. Moore, 

, 779-80 (8th
Cir. 1998), cert. denied, 

& 1082 (1998). The record lacks adequate
grounds for us to conclude that the district court abused its discretion.

                                         III.
      Mr. Purkey also maintains that the district court erred in several respects during
the guilt phase of his trial.

                                           A.
       We begin with Mr. Purkey's contention that the district court erred by refusing
to allow certain evidence during the guilt phase of the trial. He asserts that the district
court erred in the following ways: by excluding the testimony of defense expert
Dr. David Preston; by refusing to allow Mr. Purkey to testify about how his father had
introduced him to prostitutes at an early age; and by refusing to permit cross-
examination of Michael Speakman regarding his misconduct while he was
incarcerated at CCA-Leavenworth. "We review de novo the district court's
interpretation and application of the rules of evidence, and review for an abuse of
discretion the factual findings supporting its evidentiary ruling." United States v.
Smith, 

, 706 (8th Cir. 2004). We may affirm on any ground supported
by the record, even if that ground was not relied on by the district court. See Bilal v.
Lockhart, 

, 645 (8th Cir. 1993), cert. denied, 

(1993).

        Dr. Preston, a nuclear medicine specialist, conducted positron emission
topography and magnetic resonance imaging testing upon Mr. Purkey and would have
testified that those tests revealed abnormalities within Mr. Purkey's brain. Mr. Purkey
intended to offer this testimony during the guilt phase of the trial to support both his
contention that he did not intentionally kidnap Ms. Long (because he thought she was
a prostitute and/or voluntarily accompanied him to his home) and to illuminate

                                           -14-
Mr. Purkey's state of mind when he confessed to Detective Howard and Agent
Tarpley. The district court concluded that "although Dr. Preston is qualified in the
field of nuclear medicine, he is not qualified to testify regarding defendant's state of
mind and actions at the time of the offenses or at the time that Mr. Purkey gave his
statements to the investigators."

       We believe that the district court's conclusion was correct. Although we harbor
no doubt that Dr. Preston was qualified to testify regarding the results of the tests that
he conducted on Mr. Purkey, there is nothing in the record that indicates that he was
qualified to connect that testimony to the inquiry for which it was offered, namely,
Mr. Purkey's state of mind and actions either at the time of the offenses or when he
gave his statements to the investigators. Indeed, in neither the expert report nor the
offer of proof did Dr. Preston even attempt to tie the test results to Mr. Purkey's state
of mind on the specific occasions in question. When questioned by the government,
moreover, Dr. Preston admitted that the images produced by the tests could not predict
behavior and did not have a causal relationship to criminal behavior. There is
manifestly no error in the district court's decision to exclude Dr. Preston's testimony.

       Mr. Purkey also argues that the court erred when it refused, in the guilt phase
of the trial, to allow him to testify that his father had introduced him to the use of
prostitutes during his boyhood. (The court did permit some testimony of this nature
in the penalty phase.) Mr. Purkey submits that this testimony would have provided
the jury with context to understand why he might have mistakenly believed that
Ms. Long was a prostitute. This, he argues, would have bolstered his defense that he
did not kidnap Ms. Long and that she willingly entered his car and traveled with him
from Missouri to Kansas. And, defense counsel argues, if the jury believed that
Mr. Purkey did not transport Ms. Long across state lines against her will and did not
do so with the intent to rape her, it could not have convicted him of kidnapping. But
we fail to see how the method by which Mr. Purkey was introduced to prostitutes
more than thirty years before his crime is relevant to explaining why he mistook a

                                          -15-
teenage schoolgirl for a prostitute, and we therefore uphold the district court's decision
to exclude the testimony.

      Mr. Purkey also argues that the district court erred by refusing to permit him to
cross-examine Michael Speakman regarding Mr. Speakman's uncharged misconduct
while at CCA-Leavenworth. Mr. Purkey wanted to elicit this testimony to
demonstrate that a desire to avoid punishment for these uncharged acts might have
motivated Mr. Speakman to provide information and testimony for the prosecution.
He asserts that this denial deprived him of his sixth amendment right to confront an
adverse witness.

       Mr. Purkey calls our attention to the Supreme Court's language in Davis v.
Alaska, 

, 316-17 (1974), which recognizes that "the exposure of a
witness' motivation in testifying is a proper and important function of the
constitutionally protected right of cross-examination.” 

But this passage
does not suggest that a judge should be prevented from imposing limits of any sort on
defense counsel's inquiry into the potential bias of a prosecution witness. Delaware
v. Van Arsdall, 

, 679 (1986). "On the contrary, trial judges retain wide
latitude ... 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." 

not
reverse a trial court's decision to limit cross-examination absent a "clear abuse of
discretion and a showing of prejudice to [the] defendant." United States v. Love,

, 984 (8th Cir. 2003).

      Mr. Purkey has failed to demonstrate a violation of the confrontation clause.
To do so, he must show that a reasonable jury might have received a different
impression of the witness's credibility had Mr. Purkey's counsel been permitted to
pursue his proposed line of cross-examination. See Van 

;
United States v. Drapeau, 

, 875-76 (8th Cir. 2005). Here, Mr. Purkey's

                                          -16-
counsel conclusively demonstrated by other means that Mr. Speakman was driven to
testify by a desire for leniency. Mr. Speakman's testimony established that the
government had filed a motion under Federal Rule of Criminal Procedure 35,
requesting a reduction of Mr. Speakman's sentence. Mr. Purkey's counsel asked
Mr. Speakman, "Basically what you're trying to do is do your best to get a reduction
to your sentence?" Mr. Speakman replied, "I'd be lying if I said I was sitting here
being a good citizen." Mr. Purkey's counsel then asked, "Your sole point in being
here is to reduce the sentence that you received?" Mr. Speakman replied, "Yes,
ma'am." We have difficulty imagining how further testimony could have shown more
definitively that a desire for leniency played a significant part in Mr. Speakman's
willingness to testify. Consequently, the district court did not abuse its discretion in
limiting cross-examination that would have further established that point.


                                           B.
       Mr. Purkey also submits that the district court incorrectly instructed the jury on
the elements contained in the kidnapping statute. See 18 U.S.C. § 1201. That statute
provides that a person commits the offense of kidnapping if he or she "unlawfully
seizes, confines, inveigles, decoys, kidnaps, abducts, or carries away and holds for
ransom or reward or otherwise any person ... when – (1) the person is willfully
transported in interstate or foreign commerce." 

quite clearly requires
that the government prove that Mr. Purkey seized Ms. Long "for ransom or reward or
otherwise," 

this case was for the purpose of forcible rape. Mr. Purkey,
however, contends that the statute also requires that the government prove that he
transported Ms. Long across state lines for that same reason. He bases this contention
on the language of the statute that requires the defendant to have "willfully
transported," 

her victim. He submits that this phrase requires that the
kidnapper transport his or her victim with the intent to do something that the law
forbids. Cf. United States v. Gabaldon, 

, 1094-95 n.1 (10th Cir. 2004),
cert. denied, 

(2005). He therefore maintains that the district court
erred by failing to give an instruction that required the government to prove not only

                                          -17-
that he seized the victim for the purpose of forcible rape but also that he transported
her across the state line for the purpose of forcible rape. This error is significant,
according to Mr. Purkey, because he argued as part of his defense that he transported
Ms. Long from Missouri to Kansas without the intent to rape. We will affirm if the
instructions correctly stated the law and fairly and adequately submitted the issues to
the jury. Cf. United States v. Kehoe, 

, 593 (8th Cir. 2002), cert. denied,

(2003).


       The district court instructed the jury that in order to convict it had to find that
"the defendant unlawfully seized, confined, kidnapped, abducted, carried away or held
Jennifer Long;" that "the defendant did so for the purpose of the forcible rape of
Jennifer Long;" that "the defendant willfully, knowingly, and unlawfully transported
Jennifer Long across the state line from Missouri to Kansas;" and that "Jennifer Long
died as a result of defendant's actions." This instruction precisely tracked the statute's
ordering of the elements. See 18 U.S.C. § 1201. And, although the Eighth Circuit
Manual of Model Jury Instructions (Criminal) (2005) does not contain a recommended
instruction on kidnapping, the instruction given by the district court is consistent with
the recommended instructions for the Ninth and Eleventh Circuit, see Ninth Circuit
Manual of Model Jury Instructions (Criminal) § 8.95 (2003 ed.); Eleventh Circuit
Pattern Jury Instructions (Criminal) 49 (2003 ed.), as well as the instruction
recommended by the Federal Judicial Center, Pattern Criminal Jury Instructions § 84.
Cf. Eighth Circuit Manual of Model Jury Instructions (Criminal) 12.07A. We disagree
with Mr. Purkey's construction of the statute and therefore find no error in the district
court's instruction on the elements contained in § 1201.




                                          -18-
                                            C.
        In his last contention of error with respect to the guilt phase of his trial,
Mr. Purkey maintains that the district court erred in denying his motion for a mistrial
based on prosecutorial misconduct. He asserts that the government's efforts to call
attention to his tattoos that depicted, among other things, a Nazi swastika and symbols
of the Aryan Brotherhood unfairly inflamed the jury and deprived him of his right to
a fair trial.


       During the government's direct examination of its first witness, it displayed a
picture of Mr. Purkey standing shirtless with his tattoos visible. Due to a
misunderstanding between the prosecution and the defense, Mr. Purkey's counsel did
not have a chance to object before the government displayed the picture to the jury.
Mr. Purkey's counsel then objected to the picture's admission into evidence and that
objection was sustained. Three days later, during the government's cross-examination
of Mr. Purkey, the government again highlighted the tattoos. The prosecutor asked
Mr. Purkey whether Ms. Long observed his tattoos, including the "Nazi swastika"
tattoo, when she entered his vehicle or while she was, according to Mr. Purkey,
voluntarily kissing him while he had his shirt off. The government stated that it made
this inquiry to demonstrate the unreasonableness of Mr. Purkey's testimony that
Ms. Long voluntarily accompanied him to his home and consented to engaging in
foreplay with him. When defense counsel objected to this question, the district court
sustained the objection and instructed the jury to disregard the government's questions
about Mr. Purkey's tattoos. The defense then asked the judge to declare a mistrial
based on the prosecution's referring to the tattoos after the district court had previously
sustained the objection regarding the picture showing the tattoos. The district court
denied that request.


      "The test for reversible prosecutorial misconduct has two parts: (1) the
prosecutor's remarks or conduct must in fact have been improper, and (2) such

                                           -19-
remarks or conduct must have prejudicially affected the defendant's substantial rights
so as to deprive the defendant of a fair trial." United States v. Hernandez, 

, 458 (8th Cir.1985). Even assuming arguendo that the prosecutor's actions and
questions were improper, these actions nevertheless fail to constitute reversible error.
When determining whether the prosecutor's remarks and conduct so infected the trial
with unfairness that it deprived the defendant of a fair trial, we usually consider three
criteria: "(1) the cumulative effect of such misconduct; (2) the strength of the properly
admitted evidence of the defendant's guilt; and (3) the curative actions taken by the
trial court." 

. Here the cumulative effect of the
prosecutor's references to Mr. Purkey's tattoos was not significant. Although we do
not doubt that references of this sort can sometimes result in prejudice, the prosecution
referred to Mr. Purkey's tattoos only twice, cf. 

briefly at that. There was
also considerable evidence of guilt. Although he gave a somewhat different story at
trial, there was evidence that Mr. Purkey had confessed to the crime on multiple
occasions. Finally, the district court took prompt curative action. It sustained the
objections to the admission of the picture and to the questions regarding Mr. Purkey's
tattoos. After sustaining the latter objection, the court also instructed the jury to
disregard the questions. Cf. United States v. Uphoff, 

, 625-26 (8th Cir.
2000). We therefore reject Mr. Purkey's contention that his assertions of prosecutorial
misconduct warrant reversal.


                                          IV.

       We move now to Mr. Purkey's assignments of error regarding the penalty phase
of his trial.
                                           A.
      Mr. Purkey makes several arguments relating to the district court's evidentiary
rulings. He asserts that the district court erred in the following ways: by refusing to
permit evidence that his wife had poisoned him; by excluding the testimony of
Dr. Mark Cunningham regarding Mr. Purkey's alleged fetal alcohol exposure; by

                                          -20-
refusing to permit the surrebuttal testimony of Dr. Stephen Peterson in response to the
testimony of Dr. Helen Mayberg; by limiting the impeachment of Dr. Park Dietz; and
by allowing the government to question Dr. Peterson regarding his views on the death
penalty.


       "The Federal Death Penalty Act (FDPA) erects very low barriers to the
admission of evidence at capital sentencing hearings." United States v. Lee, 

, 494 (8th Cir. 2001), cert. denied, 

(2002). In the sentencing phase,
"[i]nformation is admissible regardless of its admissibility under the rules governing
admission of evidence at criminal trials." See 18 U.S.C. § 3593(c). One reason for
this more lenient standard is that it affords the defendant additional opportunities to
present mitigating evidence consistent with the Supreme Court's directive that to meet
constitutional requirements in capital cases " 'the sentencer ... not be precluded from
considering, as a mitigating factor, any aspect of a defendant's character or record and
any circumstances of the offense that the defendant proffers as a basis for a sentence
less than death.' " Eddings v. Oklahoma, 

, 110 (1982) (quoting Lockett
v. Ohio, 

, 604 (1978) (plurality opinion)) (emphasis omitted).


       But this does not mean that the defense has carte blanche to introduce any and
all evidence that it wishes. The trial court retains its traditional authority "to exclude,
as irrelevant, evidence not bearing on the defendant's character, prior record, or the
circumstances of his offense." 

n.12 (plurality opinion). The
FDPA, moreover, invests the judge with the authority to exclude probative
information during the penalty phase if "its probative value is outweighed by the
danger of creating unfair prejudice, confusing the issues, or misleading the jury."
18 U.S.C. § 3593(c). We review the record to determine whether the district judge
abused the discretion entrusted to him by the FDPA, see United States v. Johnson,

, 674 (7th Cir. 2000), cert. denied, 

(2001); United States
v. Hall, 

, 397 (5th Cir. 1998), cert. denied, 

(1999),

                                           -21-
abrogated on other grounds in United States v. Martinez-Salazar, 

, 310-
14 (2000), and we determine de novo the question of whether Mr. Purkey's
constitutional rights have been violated. See United States v. Washington, 

, 854-55 (8th Cir. 2003), cert. denied, 

& 899 (2003). Even if we
conclude that the district court erred, we cannot reverse or vacate a federal death
sentence on account of an error that is harmless beyond a reasonable doubt. See
18 U.S.C. § 3595(c)(2); Jones v. United States, 

, 402-05 (1999).


       Mr. Purkey contends that the district court erred by refusing to allow evidence
that his wife, Jeanette Purkey, had poisoned him. Mr. Purkey wished to use this
evidence to demonstrate that because he was operating under the influence of poison
when he murdered the elderly Kansas woman or when he killed Ms. Long, his actions
took place while he was involuntarily intoxicated or, at the very least, in an altered
mental state. When he sought to introduce the evidence in the penalty phase (he also
sought to introduce this evidence in the guilt phase), he had no evidence that the
poison he allegedly received, rat poison, had any known effect on the mind. Also, his
wife's testimony as to whether she had poisoned him during the relevant time period
was equivocal at best. During the penalty phase, the government objected to the
evidence, asserting that for both of the above reasons the presentation of this evidence
was not relevant and would be a "big diversion" for the jury. The district court
agreed.


      We cannot say that the district court erred in excluding this evidence. The
defense admitted that it had no evidence that rat poison has any psychological effects.
Therefore, this evidence could not have had any probative value to suggest that
Mr. Purkey's mind was operating under the poison's supposed influence when he
committed either of the two murders. A reasonable judge could conclude that this
evidence was both completely irrelevant to the purpose for which it was offered, cf.

n.12 (plurality opinion), and, because of the scandalous and

                                         -22-
perplexing nature of the claim, had significant potential to confuse or mislead the jury.
Cf. 18 U.S.C. § 3593(c).


       Mr. Purkey also asserts on appeal that this evidence also demonstrates his
difficult home life. Because he did not argue this below, we review for plain error,
see 

; United States v. Turner, 

, 221 (8th Cir. 1997),
and find none. To begin, we note Ms. Purkey's benevolent, if misguided, motivation
for poisoning her husband by mixing the poison with his drugs: She asserted that she
was trying to scare him into abandoning his illegal use of drugs. This evidence might
demonstrate that Mr. Purkey had someone in his life who cared about his well being.
To the extent that this evidence could be construed as illustrating Mr. Purkey's
difficult home life, we note that the record is replete with evidence of the difficult and
dysfunctional environments in which Mr. Purkey has lived, and so we cannot
conclude that the omission of this additional evidence affected his substantial rights.
See 

.


       Mr. Purkey also contends that the district court erred by refusing to allow
Dr. Cunningham to testify to his opinion that Mr. Purkey suffered from fetal alcohol
exposure. The district court excluded the evidence because Mr. Purkey could not
adduce specific evidence that his mother drank during the time that she was pregnant
with him. Mr. Purkey's offer of proof does indicate, however, that had the court
permitted Dr. Cunningham to testify on this issue he would have brought forth
significant circumstantial evidence that Mr. Purkey suffered from this affliction. First,
there was evidence that Mr. Purkey's mother abused alcohol dating back to at least
1950. (Mr. Purkey was born in 1952.) Second, there was evidence that Mr. Purkey's
mother had two other children around the time of Mr. Purkey's birth, both of whom
died, one shortly before and one shortly after birth. This, according to
Dr. Cunningham, would have been consistent with those children's fetal alcohol
exposure. Third, Dr. Cunningham would have testified that Mr. Purkey's brain

                                          -23-
condition is consistent with his having suffered fetal alcohol exposure. We think that
Dr. Cunningham's testimony regarding Mr. Purkey's fetal alcohol exposure would
have provided probative mitigating evidence. Cf. Silva v. Woodford, 

,
847 n.17 (9th Cir. 2002), cert. denied, 

(2002). Given that and the
relaxed standard set forth by 18 U.S.C. § 3593(c), we conclude that the district court
erred when it excluded this evidence simply because there was no direct evidence that
Mr. Purkey's mother drank while pregnant with him.


       Nevertheless, when we consider the record as a whole, we are satisfied that this
error was harmless beyond a reasonable doubt. See 18 U.S.C. § 3595(c)(2); 

; cf. Hitchcock v. Dugger, 

, 398-99 (1987); Chapman
v. California, 

, 24 (1967). We are confident that the jury would have
reached the sentence that it did even if the court had admitted this evidence. See

; cf. Sweet v. Delo, 

, 1158-59 (8th Cir. 1997),
cert. denied, 

(1998). The district court admitted significant expert
testimony regarding Mr. Purkey's brain abnormalities and their impact on his mental
and emotional health. The jury was not, therefore, precluded from considering
Mr. Purkey's mental and emotional impairments as potential mitigating factors; it was
merely precluded from considering one of several possible explanations as to the
cause of these alleged impairments. And, although we recognize that a jury may be
more likely to believe that someone suffers from a problem if its cause is explained,
we nevertheless harbor no doubt that considering the minimal probative value of the
evidence and the overwhelming evidence and jury findings of serious aggravating
factors, its exclusion was harmless. Cf. United States v. Bernard, 

, 487
(5th Cir. 2002), cert. denied, 

(2003).


        Mr. Purkey also assigns error in the district court's refusal to allow him to
impeach Dr. Park Dietz by inquiring into an error that the doctor made when testifying
in the case of Yates v. State, Nos. 01-02-00462/00463, 

(Tex. Ct. App.

                                         -24-
Jan. 6, 2005). When serving as an expert witness for the state in the Yates case,
Dr. Dietz erroneously testified that the facts of an episode of a television show on
which he consulted, "Law & Order," were very similar to those in Yates. In fact, no
such episode existed. 

Dr. Dietz, during a proffer session conducted
outside of the hearing of the jury in Mr. Purkey's case, freely admitted to the error that
he had made in the Yates trial. The district court, however, sustained the government's
objection to testimony about the error because it would "create[] confusion and [was]
collateral."


       In response to Mr. Purkey's argument, the government asserts that the exclusion
of this evidence was proper under Federal Rule of Evidence 403. But that is not the
controlling law here. This is an FDPA case, and its evidentiary standard must govern.
See 

. Accordingly, we review this issue under the standard of
§ 3593(c), which provides for the exclusion of evidence "if its probative value is
outweighed by the danger of creating unfair prejudice, confusing the issues, or
misleading the jury." 18 U.S.C. § 3593(c); see 

.


       Although one of the court's reasons, that the testimony would "create[]
confusion," is arguably consistent with a permissible reason under the FDPA, we
cannot conclude that the district court acted correctly when it refused to permit any
inquiry into Dr. Dietz's previous mistake. This testimony would have been relevant
to demonstrate the doctor's fallibility. Further, we cannot agree with the district court
that this testimony would have resulted in confusion. Dr. Dietz freely admitted that
he erred; that was not in dispute. The nature of Dr. Dietz's error, moreover, was not
unusually complex or confusing. Therefore we can find no reason to conclude that
the probative value of this testimony was "outweighed by the danger of creating unfair
prejudice, confusing the issues, or misleading the jury," 18 U.S.C. § 3593(c).




                                          -25-
       We nevertheless conclude that the error was harmless. Mr. Purkey's cross-
examination of Dr. Dietz was otherwise extensive. During that cross-examination,
Mr. Purkey was able to extract concessions from Dr. Dietz that he had made mistakes
in two other cases in which he had testified. And, although we do not doubt that the
excluded information would have provided a morsel of additional probative evidence
of Dr. Dietz's ability to err, given the otherwise extensive cross-examination that
allowed the defense to bring out his other errors, and the overwhelming number and
the nature of the aggravating factors found by the jury, we cannot conclude that the
absence of this additional information affected Mr. Purkey's substantial rights. See
18 U.S.C. § 3595(c)(2); 

; 

; cf.

; 

.


       Mr. Purkey also maintains that the district court erred by denying his request
to allow Dr. Peterson to present surrebuttal testimony in response to the testimony of
Dr. Helen Mayberg. Dr. Mayberg's testimony was presented to rebut the conclusions
of the defense's experts regarding Mr. Purkey's alleged brain injuries. The defense
requested that it be allowed to introduce surrebuttal evidence pertaining to two of
Dr. Mayberg's conclusions: that Mr. Purkey could not have suffered significant brain
injuries in automobile accidents that occurred in 1968 and 1972, and that Mr. Purkey's
functioning as a "jailhouse lawyer" was inconsistent with the sort of brain damage
reported by the defense's medical experts.


      The government argues that the court did not err in excluding this surrebuttal
testimony because Dr. Mayberg's rebuttal testimony did not raise a new matter. The
decision of whether to allow a party to present evidence in surrebuttal is generally
committed to the discretion of the trial court, see United States v. Wilford, 

, 452 (8th Cir. 1983), cert. denied, 

(1984), and surrebuttal is
typically thought appropriate only when new matters are raised in the rebuttal



                                        -26-
testimony, see United States v. Barnette, 

, 821 (4th Cir. 2000); cf.

.


       We do not think that the FDPA alters this standard. Cf. 

. Although the FDPA dispenses with the rules governing the admission of
evidence during criminal trials, it is not sensible to read this statutory imperative as
also divesting the trial judge of his or her traditional authority to control the mode and
order of the interrogation of witnesses and the presentation of evidence. A contrary
reading would transform the FDPA sentencing hearing into an evidentiary mélee.


       Even assuming that Dr. Mayberg's testimony that Mr. Purkey's work as a
"jailhouse lawyer" demonstrated his lack of significant brain damage presented a new
matter, thereby making surrebuttal appropriate, we cannot conclude that this putative
error provides an adequate ground for reversal. As mentioned previously, Mr. Purkey
presented a significant amount of testimony regarding his assertion that he suffered
from brain damage. This additional testimony would have, at best, offered only
marginal additional support for this defense. When we consider this fact combined
with the significant number and serious nature of the aggravating factors advanced by
the government and found by the jury, we cannot conclude that this error affected
Mr. Purkey's substantial rights. See 18 U.S.C. § 3595(c)(2); 

-
05; 

; cf. 

; 

.

      Finally, Mr. Purkey asserts that the district court erred by overruling his
objection to questions that the government asked on cross-examination of
Dr. Peterson, one of Mr. Purkey's expert witnesses. Specifically, Mr. Purkey's counsel
objected to the government's inquiry into Dr. Peterson's views on the death penalty.

      Even under the traditional rules of evidence, "cross-examination regarding
potential bias of a witness is proper." United States v. Amerson-Bey, 

,

                                          -27-
682 (8th Cir. 1990); see United States v. McCoy, 

, 760-61 (8th Cir. 1997)
(per curiam). If Dr. Peterson strongly disfavored the death penalty, knowledge of that
would be relevant to the jury's evaluation of his credibility in testifying to factors that
could mitigate Mr. Purkey's sentence; " 'exposure of a witness' motivation in testifying
is a proper and important function of ... cross-examination,' " Van 

(quoting 

). To the extent that the FDPA alters this
rule, it relaxes it, see 18 U.S.C. § 3593(c); 

; a fortiori the district
court did not err in allowing the government to continue its line of inquiry into
Dr. Peterson's beliefs about the death penalty.

       In addition to considering whether each of the evidentiary errors that we have
found is individually sufficient to require reversal, we have also considered, sua
sponte, what cumulative effect these errors might have had upon Mr. Purkey's
substantial rights. Cf. United States v. Steffen, 

, 597-98 (8th Cir. 1981),
cert. denied, 

(1981). After careful review, we also conclude that the
errors, even when taken cumulatively, are harmless.

                                           B.
       Mr. Purkey next maintains that the district court erred by denying his motion
for allocution during the penalty phase of the trial; Mr. Purkey sought to make a
statement before the jury without being subject to cross-examination. Although
Mr. Purkey was permitted to address the district court before it imposed his sentence,
he argues that the court functionally deprived him of his right to allocution, because
it lacked any discretion to impose a sentence other than the one that the jury already
had recommended, see 18 U.S.C. § 3594. The district court's error, he maintains,
violated his constitutional rights, Rule 32 of the Federal Rules of Criminal Procedure,
and the FDPA, see 18 U.S.C. §§ 3592(a)(8), 3593(c). We disagree.

     First, our circuit previously has recognized that the right to allocution does not
emanate from the Constitution. See United States v. Patterson, 

, 1260

                                           -28-
(8th Cir. 1997) (per curiam); see also 

; 

.
Therefore, even if Mr. Purkey were correct that the district court denied him the right
to allocution, the error would not be a constitutional one.

       Second, Mr. Purkey does not have a statutory right to make statements to a jury
during the penalty phase of an FDPA trial without being subject to cross-examination.
Rule 32(i)(4)(A)(ii) requires that "[b]efore imposing sentence," the district court must
"permit the defendant to speak or present any information to mitigate the sentence."
The district court satisfied Rule 32 when it allowed Mr. Purkey to speak "before
imposing sentence." See 

. Although Mr. Purkey's allocution
could not have mitigated his sentence because it followed the jury's recommendation
of the death penalty, see 18 U.S.C. § 3594, nowhere does Rule 32 grant Mr. Purkey
a right to allocution before a jury; Rule 32 speaks only of "the court." We agree with
the Fifth Circuit that Rule 32(i)(4)(A)(ii) should not be interpreted to entitle
Mr. Purkey to a right of allocution before the jury "when the plain language of the rule
does not dictate such an interpretation." 

; see also 

. As for the FDPA, nowhere does it mention a right to allocution or
anything comparable; Mr. Purkey's claimed right on that ground therefore does not
exist.

                                           C.
       Mr. Purkey assigns several errors relating to the jury's special findings and
recommendation of his death sentence. We previously noted that, to recommend a
death sentence after determining that the defendant is eligible for such a sentence, the
jury must unanimously find that the statutory and non-statutory aggravating factors
"sufficiently outweigh" the mitigating factors. See 18 U.S.C. § 3593(e). For an
aggravating factor to enter into the jury's calculation, the government must establish
"the existence of such a factor ... beyond a reasonable doubt." 

3593(c). The
standard for mitigating factors, however, is less rigorous. The jury may consider any
mitigating factor that at least one juror found proved "by a preponderance of the

                                         -29-
information." 

3593(c), (d). After the jury has completed its deliberations, it
must "return special findings identifying any aggravating factor ... found to exist." 

3593(d).

       Mr. Purkey first contends that the district court erroneously permitted the
prosecution to present the jury with duplicative aggravating factors, thereby skewing
the jury's balancing of aggravating and mitigating factors in violation of the eighth
amendment. Because Mr. Purkey challenges the constitutionality of allegedly
duplicative aggravating factors, we review the district court's decision de novo. Cf.
Cooks v. Ward, 

, 1289 (10th Cir. 1998).

      Mr. Purkey's best case for duplication is that the nonstatutory aggravator for
"[s]ubstantial criminal history" mirrors the statutory aggravator for convictions of
"two or more offenses punishable by a term of imprisonment of more than one year,
committed on different occasions, involving the infliction and attempted infliction of
serious bodily injury and death upon another person." The convictions that the
government offered to support both aggravating factors were identical.

       We think that the Tenth Circuit is correct to conclude that the same facts can
support different inferences that form different aggravators. See Medlock v. Ward,

, 1319 (10th Cir. 2000) (per curiam), cert. denied, 

(2000).
Otherwise the government would either have to choose one out of several possible
aggravating factors for each instance of a defendant's misconduct or pack into a single
aggravator multiple negative inferences that could be drawn from the misconduct and
then risk the jury's rejection of the aggravator due to disagreement over just one of the
inferences.

       Even under the Tenth Circuit's standard, however, we agree with Mr. Purkey
that the nonstatutory aggravating factor duplicated the statutory one. The government
used the same set of convictions each time for the same purpose, namely to show the

                                          -30-
defendant's criminal history. The nonstatutory aggravating factor did refer to a fact
of Mr. Purkey's criminal history that went unmentioned in the statutory aggravating
factor, namely, that Mr. Purkey "shot Gregg W. Carlberg on or about August 3, 1980."
Even if this fact were enough to distinguish the two aggravators, though, it overlaps
with a separate statutory aggravating factor based on Mr. Purkey's conviction of "an
offense punishable by a term of imprisonment of more than one year, involving the
use ... of a firearm ... against another person," 18 U.S.C. § 3592(c)(2) – an aggravator
that went to the same history of illegal firearm use as did the shooting episode.

       Despite the duplication of aggravators in Mr. Purkey's case, we see no basis for
the constitutional infirmity of such factors. The Supreme Court has "never before held
that aggravating factors could be duplicative so as to render them constitutionally
invalid," 

(plurality opinion), and we decline to do so when the
FDPA avoids arbitrary death sentences by requiring juries to weigh aggravating and
mitigating factors rather than to tally the factors on each side and declare a winner
based on sheer numbers. See 18 U.S.C. § 3593(e). But see United States v. Tipton,

, 899 (4th Cir. 1996), cert. denied, 

(1997); United States
v. McCullah, 

, 1111-12 (10th Cir. 1996), cert. denied, 

(1997). The district court's jury instructions bolster this view as applied to
Mr. Purkey's case: The district court ensured that the jury would not employ a tally
method of evaluating factors when it instructed the jury that "weighing aggravating
and mitigating factors ... is not a mechanical process. In other words, you should not
simply count the number of aggravating and mitigating factors. The law contemplates
that different factors may be given different weights or values by different jurors."

       Of course, had the government introduced an invalid aggravating factor into the
jury's weighing process, then the government might have violated Mr. Purkey's rights
under the eighth amendment. See Stringer v. Black, 

, 232 (1992). But
Mr. Purkey asserts no such error here.



                                         -31-
       Mr. Purkey next requests that our circuit reconsider its precedents that have
approved jury instructions mandating that a jury recommend a sentence of death
should it conclude, after balancing aggravating against mitigating factors, that the
former sufficiently outweigh the latter to justify imposition of a death sentence. He
recognizes that overruling those precedents would require the action of our en banc
court and that, as a panel of that court, we are required to give them effect. See United
States v. Provost, 

, 622 (8th Cir. 1992). For our part, we believe that our
precedents are well-reasoned. See 

; 

.

       Finally, Mr. Purkey maintains that the FDPA requires juries to identify any
mitigating factor that at least one juror found to exist and that the district court
consequently erred by accepting the jury's verdict form. (The verdict form asked the
jury to record the number of jurors who found each mitigating factor to exist, and the
jury returned that portion of the form blank.) Because Mr. Purkey presents us with
a question of law by asking us to interpret the FDPA, we review de novo the district
court's refusal to order the jury to complete the mitigation portion of the verdict form.
See United States v. Storer, 

, 921 (8th Cir. 2005).

        In a prior case, we hinted that the FDPA does not mandate that jurors identify
the mitigating factors they find to exist, but we ultimately avoided deciding the
question. See United States v. Paul, 

, 999 n.6 (8th Cir. 2000) (citing

). We conclude that in Paul we correctly, albeit tentatively,
construed the FDPA. Section 3593(d) specifically requires the jury to "return special
findings identifying any aggravating factor[s] ... found to exist," without any mention
of identifying such mitigating factors, and so requires no special findings with respect
to the latter. It is true that the jury's identification of proven mitigating factors
facilitates appellate review, especially when we have to evaluate the effect of any error
on the sentence that the jury recommended. Nevertheless, the jury's failure to identify
proven mitigating factors is entirely proper under the FDPA, and therefore the district
court did not err by accepting the jury's verdict form.

                                          -32-
                                          D.
       In Mr. Purkey's last assignment of error, he argues that the district court erred
by denying his motion for a mistrial based on alleged prosecutorial misconduct.
During the penalty phase of the trial, Mr. Purkey interrupted the government's cross-
examination of a psychiatric expert for the defense, at which point the district court
excused the jury and Mr. Purkey gave voice to an additional comment that the
prosecutor interpreted as a threat against him. During the government's subsequent
cross-examination of a defense expert, who testified to the calming effects of
medication that Mr. Purkey was taking, the prosecutor asked the expert whether he
was "aware [that Mr. Purkey] threatened to run my head through yesterday in court,"
to which Mr. Purkey's counsel immediately objected. The district court sustained the
objection. Mr. Purkey contends that the prosecutor's question compromised the
fairness of the penalty proceedings.

        Earlier in our opinion, we rehearsed the legal principles that guide our review
of alleged prosecutorial misconduct. Cf. 

. Even if, as
Mr. Purkey claims, the prosecutor's question was improper, we conclude that the
question did not deprive Mr. Purkey of due process: Although the district court failed
to instruct the jury to disregard the prosecutor's question, it sustained defense counsel's
objection. Given that defense counsel did not request the court to give the jury a
cautionary instruction and that the question was brief and isolated, the district court's
curative action, combined with the overwhelming evidence of aggravating factors,
ensured that Mr. Purkey was not denied a fair penalty proceeding. See 

true even when we take into account any residual effect on the jury from the
instances of improper prosecutorial conduct that related to Mr. Purkey's tattoos and
occurred during the guilt phase of Mr. Purkey's trial. We therefore conclude that the
district court did not err when it denied Mr. Purkey's motion for a mistrial.




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                                V.
Accordingly, we affirm the judgment of the district court.
                     ______________________




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