United States Court of Appeals
                            FOR THE EIGHTH CIRCUIT
                                    ___________

                                    No. 05-2436
                                    ___________

United States of America,                *
                                         *
             Appellee,                   *
                                         * Appeal from the United States
      v.                                 * District Court for the
                                         * District of Nebraska.
Christopher L. Grant, also known as      *
Lil Nut, also known as Little Nuts,      *      [UNPUBLISHED]
                                         *
             Appellant.                  *
                                    ___________

                              Submitted: December 14, 2005
                                 Filed: January 31, 2006
                                  ___________

Before MELLOY, COLLOTON, and BENTON, Circuit Judges.
                          ___________

PER CURIAM.

      After a jury trial, Christopher L. Grant was convicted of conspiracy to distribute
cocaine base, in violation of 21 U.S.C. §§ 841 and 846, and was sentenced to 170
months’ imprisonment. Grant appeals, and we affirm.

        The government at trial presented the testimony of ten witnesses, eight of whom
testified that he or she either had participated in or witnessed a cocaine base
transaction involving Grant. Many of the witnesses also testified to their own criminal
histories, and six indicated some hope that their testimony against Grant might result
in leniency in their own cases. Six witnesses also admitted to prior convictions for
giving false information to the police.

        After considering this evidence, including the impeachment material, the district
court1 denied Grant’s motion for judgment of acquittal and the jury returned a guilty
verdict. The jury was further asked to determine, unanimously and beyond a
reasonable doubt, the quantity of drugs attributable to Grant. On this question, the
jury found that Grant had conspired to distribute “[a]t least 5 grams, but less than 50
grams” of a substance containing detectable amounts of cocaine. Based on this
finding, the United States Probation Office recommended a base offense level of 30
in its presentence report (“PSR”). See USSG § 2D1.1(a)(3), (c)(5). The PSR further
recommended a two-level adjustment for obstruction of justice, resulting in a total
offense level of 32. With his criminal history category of V, Grant was subject to an
advisory guidelines range of 188-235 months.

       At sentencing, the district court2 rejected the PSR’s recommended adjustment
for obstruction of justice, finding that the government had not met its burden of proof.
The court also considered but rejected the government’s argument that the jury’s drug
quantity finding was not binding on the district court, given the lower standard of
proof applicable to calculations under the advisory guidelines. Cf. United States v.
Vaughn, 

, 1004 (8th Cir. 2005), cert. denied, 

(Jan. 9,
2006). The court did find that Grant’s drug quantity fell at the high end of the range
determined by the jury, and held him responsible for more than 35 but less than 50
grams of cocaine base. Based on these findings, Grant’s advisory guideline range was
151-188 months, and the statutory range was ten years to life imprisonment. The


      1
        The Honorable Thomas M. Shanahan, United States District Judge for the
District of Nebraska.
      2
        The Honorable Laurie Smith Camp, United States District Judge for the
District of Nebraska.

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court determined that a sentence at the middle of the advisory range was appropriate
and reasonable, and imposed a sentence of 170 months.

        Grant argues that the evidence was insufficient to support his conviction. We
view the evidence in the light most favorable to the government and will overturn a
verdict only if no reasonable jury could have found the defendant guilty beyond a
reasonable doubt. United States v. McKay, 

, 1094 (8th Cir. 2005).
“Attacks on the sufficiency of the evidence that call on this court to scrutinize the
credibility of witnesses are generally not an appropriate grounds for reversal,” for “[i]t
is the task of the jury to evaluate the credibility of witnesses.” 

omitted).

       To prove Grant’s participation in a conspiracy, the government was required
to demonstrate that there was an agreement to achieve an illegal purpose, and that
Grant knew of the agreement and intentionally associated with it. 

not
be an express agreement, and circumstantial evidence may suffice to prove the
necessary tacit understanding. United States v. Adams, 

, 893-94 (8th
Cir.), cert. denied, 

(2005).

        Grant argues that the government failed to prove that he was aware of or
involved in any drug conspiracy. But the government adduced over a half-dozen
witnesses who testified that they observed Grant buying and selling crack cocaine at
various houses in the area, often in quantities indicative of an intent to redistribute.
If believed, this testimony was sufficient to show that Grant was a knowing participant
in an agreement to distribute cocaine base. See United States v. Oleson, 

, 1089 (8th Cir. 2002). The determination whether to believe those witnesses was
within the province of the jury.

      Grant also argues that the district court erred in calculating the advisory
guideline range by finding him responsible for a greater quantity of drugs than was

                                           -3-
supported by the evidence. This argument is without merit. The drug quantity, like
the conspiracy in general, was amply supported by the testimony of multiple witnesses
if believed, and there is no clear error in the district court’s reliance on that testimony.
See United States v. Johnston, 

, 625 (8th Cir. 2003) (per curiam).

       Finally, Grant asserts that the sentencing resulted in a violation of his Sixth
Amendment rights because the district court made factual determinations “better left
for the jury.” (Appellant’s Br. at 13). Grant was sentenced under the advisory
guidelines scheme announced in United States v. Booker, 

, 757 (2005),
and judicial fact-finding does not violate the Sixth Amendment when done in the
context of an advisory guidelines scheme. United States v. Winters, 

,
858 (8th Cir. 2005).

       For these reasons, the judgment of the district court is affirmed.
                         ____________________________




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