United States Court of Appeals
                            FOR THE EIGHTH CIRCUIT
                                    ___________

                                    No. 07-2131
                                    ___________

United States of America,                *
                                         *
             Appellee,                   *
                                         * Appeal from the United States
      v.                                 * District Court for the
                                         * District of Nebraska.
Harley Tyndall,                          *
                                         *
             Appellant.                  *
                                    ___________

                              Submitted: December 12, 2007
                                 Filed: April 4, 2008 (Corrected: 4/25/2008)
                                  ___________

Before LOKEN, Chief Judge, WOLLMAN, and SHEPHERD, Circuit Judges.
                             ___________

WOLLMAN, Circuit Judge.

       Harley Tyndall was convicted by a jury of sexual abuse of a minor in violation
of 18 U.S.C. § 2243(a). He was acquitted of engaging or attempting to engage in a
sexual act with a person who was physically incapable of consenting in violation of
18 U.S.C. § 2242(2). He was sentenced to 120 months’ imprisonment and now
appeals, contending that the district court1 erred in denying his motions for acquittal,
mistrial, and new trial, as well as in imposing sentence. We affirm.



      1
        The Honorable Laurie Smith Camp, United States District Judge for the
District of Nebraska.
                                          I.

      Megana Rivera and her husband, Robert, who is Tyndall’s cousin, live in
Walthill, Nebraska, on the Omaha Nation Indian Reservation. In the early morning
hours of February 5, 2006, Tyndall and Megana returned after a night of dancing and
drinking to Megana’s home, where they continued to consume alcohol. Robert, who
was working his night shift, was not present. Megana had hired her 15-year-old
cousin M.R., her regular babysitter, to babysit her two small children while she was
out. M.R. was encouraged to join Tyndall and Megana in a drinking game that left
M.R. vomiting and passing in-and-out of consciousness. Upon regaining
consciousness, M.R. went to a spare bedroom, where she fell asleep.

       According to Tyndall’s testimony, a highly intoxicated Megana grabbed his
crotch as he was about to leave, causing him extreme pain because of a cut on his
penis that he had recently suffered. He went to the bathroom and discovered that the
cut had been opened and was bleeding, resulting in some blood on his underwear and
hands. He did not refasten his pants because doing so put too much pressure on his
injured penis. From the spare bedroom across the hall from the bathroom, M.R. called
him into the room and told him she wanted to “get” with him, whereupon they kissed
consensually. Tyndall testified that although M.R. pulled his hand to her crotch, he
did not penetrate any part of her genital area. Recalling M.R.’s age, he pushed her
away and then went into the living room, where he decided to wait for Robert to return
to the home so that he could explain what had happened. Megana entered the living
room and asked what Tyndall had done to M.R. He tried to explain that nothing had
occurred because his injury, which he then showed to Megana, was too painful to
permit sexual intercourse. Megana ordered him out of the home and then called the
tribal police.

      M.R. testified that the next thing that she remembered after falling asleep was
regaining consciousness long enough to see Tyndall between her legs and to feel

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pressure in her vagina, after which she again passed out. After regaining
consciousness, she was asked by Megana why she was wearing only a shirt and what
Tyndall had done to her.

       Megana testified that she had ordered Tyndall to leave, whereupon he showed
her his injury. She then helped M.R. to the bathroom, where she told M.R. to sit on
the toilet and wipe herself. Megana observed that the toilet paper M.R. used had
blood on it, whereupon M.R. began to cry and flushed the toilet paper away. Megana
then called the tribal police.

       The medical examination of M.R. revealed no evidence of trauma, bruises,
scrapes, or abrasions that would indicate sexual activity, and her hymen was still
intact. The examining doctor testified that these results were not uncommon in sexual
assault victims and that they did not rule out the possibility of sexual activity. M.R.’s
period had ended days earlier. A rape kit examination revealed the existence of a
bacteria called ureaplasma, which is passed almost exclusively by sexual contact.
M.R. testified that she had never had sexual intercourse before the incident with
Tyndall. M.R.’s DNA was found on Tyndall’s underwear.

        Investigating officer Bernard Morris testified on cross-examination that he saw
a piece of tissue paper with blood on it in the bathroom. On redirect examination, he
testified that there was no bloody tissue included with the evidence gathered at the
scene, and that what he had really seen was a bloody carpet fiber. On recross
examination, he testified that what he saw was a bloody tissue, perhaps in the
wastebasket. On the second redirect examination, he again stated that what he saw
was bloody carpet fibers, not tissues. He testified that all relevant evidence had been
collected and turned over to the FBI. No bloody tissue appeared in any police
photograph taken that night. No other officer saw the alleged tissue paper, and none
was ever logged as evidence.



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                                          II.

      Tyndall contends that the prosecution’s failure to disclose the fact of Officer
Morris’s belief in the existence of a bloody tissue paper constituted a violation of
Brady v. Maryland, 

(1963), that entitles him to a new trial.

       We review for abuse of discretion the denial of a motion for a mistrial, United
States v. Gray, 

, 1027 (8th Cir. 2004), as we do a denial of a motion for
a new trial based on a Brady violation. United States v. Haskell, 

, 1075
(8th Cir. 2006). We review de novo a denial of a motion for a judgment of acquittal.
United States v. Stanko, 

, 411 (8th Cir. 2007).

       The Supreme Court held in Brady that “the suppression by the prosecution of
evidence favorable to an accused upon request violates due process where the
evidence is material either to guilt or to punishment, irrespective of the good faith or
bad faith of the 

. Brady is violated if three requirements
are met: “The evidence at issue must be favorable to the accused, either because it is
exculpatory, or because it is impeaching; that evidence must have been suppressed by
the State, either willfully or inadvertently; and prejudice must have ensued.” Morales
v. Ault, 

, 554 (8th Cir. 2007) (quoting Strickler v. Greene, 

,
281-82 (1999)). The evidence is not material and no prejudice can be shown unless
there is a reasonable probability that the verdict would have been different if the
evidence had not been suppressed. 

; Johns v. Bowersox, 

, 545 (8th Cir. 2000). A prosecutor has a duty to disclose evidence known
by police officers, even if not known by the prosecutor, because a prosecutor has a
duty to learn of such information. 

. The underlying
question is whether the verdict is worthy of confidence. United States v. Almendares,

, 664 (8th Cir. 2005). A mid-trial disclosure violates Brady only if it
comes too late for the defense to make use of it. 

argues that the existence of a bloody tissue would support his
contention that his penis was so severely injured that he would not have engaged in
sexual activity. Because there appears to be no question that Tyndall had such an
injury, however, and that he was bleeding from it that night, the effect of this evidence
would have been cumulative, at best. Accordingly, we conclude that there is no
reasonable probability that the verdict would have been different if Tyndall had
known before trial that Officer Morris thought he saw a tissue with blood on it in
Megana’s bathroom.

        Additionally, the disclosure was not so untimely that Tyndall could not make
use of it at trial. The district court granted an extended period of cross- and redirect
examination on this subject, and Tyndall does not provide any reason to believe that
further cross-examination of any witnesses could have aided his cause. Indeed,
Tyndall did not request to recall for further cross-examination the officer who had
testified prior to Officer Morris’s testimony. Tyndall argues that he would have been
able to impeach M.R.’s and Megana’s testimony that M.R. had flushed the bloody
toilet paper that she had used to wipe herself after the incident by proving that she had
actually disposed of that tissue in the wastebasket. Even if Tyndall had obtained the
maximum impeachment value from such testimony, however, it would not have
created a reasonable probability of a different outcome. Accordingly, the district court
did not err in denying his motions for a new trial, a mistrial, and a judgment of
acquittal.

                                          III.

       Tyndall argues that the district court erred in several respects in imposing
sentence. “We review the district court’s conclusions of law and application of the
sentencing guidelines de novo. We review factual findings for clear error.” United
States v. Fields, 

, 1011 (8th Cir. 2008) (internal citation omitted). We
give great deference to a district court’s determination of a witness’s credibility,

                                          -5-
United States v. Denton, 

, 1114 (8th Cir. 2006), and to its decision to
enhance a sentence for obstruction of justice. United States v. Frank, 

,
923 (8th Cir. 2004).

                                          A.

        The district court increased Tyndall’s offense level for obstruction of justice
after finding that he had committed perjury. To apply this enhancement, the district
court was required to have found by a preponderance of the evidence that Tyndall
willfully gave false testimony on a material matter. United States Sentencing
Guidelines (U.S.S.G.) § 3C1.1; United States v. Dunnigan, 

, 94 (1993);
United States v. Ziesman, 

, 956 (8th Cir. 2005). The bare fact of
conviction following the defendant’s testimony is insufficient to support an
obstruction of justice enhancement. United States v. Abdul-Aziz, 

, 478-
79 (8th Cir. 2007). A district court’s failure to expressly find willfulness in giving
false testimony is not grounds for reversal if the evidence of willfulness is
unequivocal and the defendant’s contradictory testimony is not a result of confusion,
mistake, or faulty memory. United States v. Brown, 

, 890 (8th Cir.
2002); United States v. Esparza, 

, 1055 (8th Cir. 2002).

       The district court found that Tyndall’s testimony was not credible and that
Megana’s and M.R.’s testimony was credible. The willful falseness of Tyndall’s
testimony is rendered unequivocal from the evidence that M.R. was discovered to
have a sexually transmitted bacteria despite her testimony that she had never before
engaged in sexual activity, the lack of any medical evidence of any trauma to M.R.
that would cause bleeding and the presence of blood visible on a tissue that M.R. used
to wipe herself, along with the presence of M.R.’s DNA on Tyndall’s underwear.
Based on this evidence, the district court did not clearly err in finding Tyndall’s
testimony not credible and did not err by enhancing his offense level for obstruction
of justice. That said, we once again emphasize the importance of detailed findings to

                                         -6-
the effect that the defendant testified falsely about a material matter with a willful
intent to deceive the factfinder. United States v. Molina, 

, 1058 (8th
Cir. 1999). See also, e.g., 

.

        Likewise, the district court did not err in refusing to grant Tyndall an offense-
level reduction for acceptance of responsibility pursuant to U.S.S.G. § 3E1.1. See
United States v. Vaca, 

, 1048 (8th Cir. 2002). It is rarely appropriate
to grant a reduction for acceptance of responsibility to a defendant whose offense level
has been increased for obstruction of justice. U.S.S.G. § 3E1.1 cmt. n.4. There is no
special circumstance in this case that warrants granting such a request. Further, a
reduction for acceptance of responsibility is not appropriate if the defendant demands
a trial at which he denies the “essential factual elements of guilt.” U.S.S.G. § 3E1.1
cmt. n.2; see United States v. Williams, 

, 383 (8th Cir. 2007), vacated,

(remanding for resentencing in light of Kimbrough v. United States,

(2007)).

                                            B.

      The district court did not err in calculating the base offense level as 30 under
U.S.S.G. § 2A3.1 rather than as level 18 under U.S.S.G. § 2A3.2. Tyndall was
convicted of sexual abuse of a minor in violation of 18 U.S.C. § 2243(a), which would
normally result in a base offense level of 18 under U.S.S.G. § 2A3.2. A cross-
reference in U.S.S.G. § 2A3.2(c), however, requires the application of U.S.S.G. §
2A3.1 if conduct proscribed under 18 U.S.C. § 2242 is a part of the offense. Tyndall
was acquitted of the charges under § 2242, which forbids “engag[ing] in a sexual act
with another person if that other person is . . . incapable of appraising the nature of the
conduct[] or . . . physically incapable of declining participation in, or communicating
unwillingness to engage in, that sexual act.” Nevertheless, a district court may use a
defendant’s relevant conduct in sentencing if it finds by a preponderance of the
evidence that the conduct occurred, even if that conduct formed the basis of a criminal

                                           -7-
charge on which a jury acquitted the defendant. United States v. Watts, 

,
156-157 (1997); United States v. No Neck, 

, 1055 (8th Cir. 2007);
United States v. High Elk, 

, 626 (8th Cir. 2006); U.S.S.G. § 6A1.3 cmt.;
see U.S.S.G. § 1B1.3(a)(1)(A). The district court found by a preponderance of the
evidence that Tyndall’s conduct violated 18 U.S.C. § 2242 because M.R.’s inebriated
state made her incapable of appraising the nature of the sexual act and physically
incapable of refusing or communicating her refusal to participate in the sexual act.
Thus, the application of the cross-reference to U.S.S.G. § 2A3.1 was appropriate.

       Tyndall argues that because the disparity in sentencing ranges is so great, the
district court should have been required to find that there was clear and convincing
evidence of the existence of the relevant conduct relied upon to enhance the sentence.
Both this court and the Supreme Court have recognized that due process might require
proof beyond a mere preponderance of the evidence if an extreme increase in the
applicable sentencing range results from the consideration of relevant conduct. See

& n.2; United States v. Townley, 

, 369 (8th Cir.
1991). We indicated, without so holding, in Townley that a seven-fold increase in the
permissible sentencing range might require the application of the clear and convincing
standard of proof as a prerequisite to the consideration of relevant but unconvicted

. We have twice held that a four-fold increase in the
permissible sentencing range does not require the use of the clear and convincing
evidence standard. See United States v. Bradford, 

, 920 (8th Cir. 2007);
United States v. Alvarez, 

, 1088 (8th Cir. 1999).

       If the relevant acquitted conduct is not considered, Tyndall’s base offense level
would be 18, plus a two-level enhancement for obstruction of justice (but no increase
for the age of the victim, which is accounted for in U.S.S.G. § 2A3.2). At criminal
history category III, Tyndall would be subject to a 51-month prison sentence. The
sentencing range for offense level 34 in criminal category III rises to 235 months,
limited by the statutory maximum under 18 U.S.C. § 2243(a) of 180 months, which

                                          -8-
would be about three-and-a-half times greater than 51 months, less than the increase
in Bradford and Alvarez. Accordingly, we conclude that an increase of this magnitude
is not so extreme as to require that the district court find the existence of relevant
conduct to have been established by clear and convincing evidence rather than by a
preponderance of the evidence.

       Finally, the district court did not err in increasing Tyndall’s offense level on the
basis of M.R.’s age. Normally, the applicable section of the guidelines for a violation
of 18 U.S.C. § 2243(a) is U.S.S.G. § 2A3.2, in which the victim’s age is already
considered, so no further enhancement for the victim’s age would be appropriate.
When the cross-reference found in U.S.S.G. § 2A3.2(c) is applied, however, U.S.S.G.
§ 2A3.1 is the relevant section. This section’s base offense level does not contemplate
that the victim is a minor and states that the offense level should be increased by two
if the victim is at least twelve but less than sixteen years old. U.S.S.G. §
2A3.1(b)(2)(B). Because M.R. was fifteen years old at the time of the incident, the
district court correctly increased the offense level by two.

      The judgment is affirmed.
                      ______________________________




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