United States Court of Appeals
                            FOR THE EIGHTH CIRCUIT
                                   _____________

                                   No. 98-2735NE
                                   _____________

United States of America,                *
                                         *
                    Appellee,            * Appeal from the United States
                                         * District Court for the District
      v.                                 * of Nebraska.
                                         *
Clyde M. Shinall,                        * [UNPUBLISHED]
                                         *
                    Appellant.           *
                                   _____________

                            Submitted: December 17, 1998
                                Filed: December 23, 1998
                                 _____________

Before FAGG, HEANEY, and WOLLMAN, Circuit Judges.
                          _____________

PER CURIAM.


      Clyde M. Shinall appeals his conviction and sentence for conspiracy to distribute
cocaine base. We affirm.

       Shinall first contends the evidence was insufficient to convict him. We will
reverse on this ground only if, viewing the evidence in the light most favorable to the
verdict and giving the Government the benefit of all reasonable inferences, we
conclude a rational jury must have had a reasonable doubt that the elements of
conspiracy were established. See United States v. Santana, 

, 864 (8th Cir.
1998). For the
jury to find Shinall conspired to distribute cocaine base, the Government had to show
there was an agreement to distribute, Shinall knew of the agreement, and Shinall
intentionally joined the agreement. See United States v. Romero, 

, 824
(8th Cir. 1998). The Government was not required to prove an express agreement, but
only a tacit understanding, which could be established by circumstantial evidence of
Shinall’s actions. See United States v. Cabrera, 

, 1245 (8th Cir. 1997).

        At Shinall’s trial, one of Shinall’s customers, Tony Rutherford, testified he and
Shinall had an understanding that Rutherford could buy distributable amounts of
cocaine base from Shinall. Rutherford testified that, given his quarter-ounce purchase,
Shinall would know Rutherford planned to resell at least some of the cocaine base, and
Shinall implicitly agreed to make future sales of that distributable amount to
Rutherford for him to resell. Although a mere sales agreement between a buyer and
seller of illegal drugs does not constitute a conspiracy, Rutherford’s testimony supports
a reasonable inference of an understanding beyond the sales agreement, which is
enough to support Shinall’s conspiracy conviction. See United States v. Jensen, 

, 833 (8th Cir. 1998); 

. In addition, Shinall’s
girlfriend, Stacy Horn, testified she provided Shinall with transportation and provided
him with a place to cook, package, and sell cocaine base. Unlike the situation in
Jensen, where the defendant’s girlfriend had no active role in helping her boyfriend
further his drug business from their home, Horn helped Shinall obtain and market his
drugs. 

. A reasonable jury could find a degree of knowing
involvement and cooperation, even if Horn did not benefit financially. See 

.

      Shinall asserts the testimony of Rutherford and Horn is incredible because they
benefited from agreements to cooperate with the Government. During cross-
examination, however, Shinall had the opportunity to expose the witnesses’ potential
bias and self-interest, and it was the jury’s job to decide whether the witnesses’
testimony was credible. See United States v. Maggard, 

, 847 (8th Cir.

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1998); 

. We conclude the evidence was sufficient to convict
Shinall of conspiracy to distribute cocaine base.

        Shinall next contends the district court committed error in denying his motion
for a new trial based on newly discovered evidence. The district court did not abuse
its discretion in denying the motion. To obtain a new trial based on newly discovered
evidence, the evidence must, among other things, be newly discovered and be likely
to produce an acquittal on retrial. See United States v. Warren, 

, 744 (8th
Cir. 1998). Neither of these criteria are satisfied here. After Horn was sentenced to
a term longer than she believed the Government had promised, she wrote a letter
stating the amount of cocaine she had seen Shinall possess was smaller than she had
testified about at trial. Information that Shinall possessed less cocaine in Horn’s
presence is not newly discovered evidence because this information was within
Shinall’s knowledge at the time of trial. See 

Further, given the other
testimony by Rutherford and Horn about Shinall’s drug-related activities, a change in
Horn’s testimony merely decreasing the amount of drugs that she saw Shinall possess
would not likely cause an acquittal on retrial. Indeed, the district court found Horn’s
recantation was incredible, so a jury would probably not believe it. See United States
v. Grey Bear, 

, 350-51 (8th Cir. 1997).

        Last, Shinall contends the district court committed clear error in calculating the
amount of cocaine base attributable to him for sentencing purposes. Because the
amount of cocaine base seized from Shinall did not reflect the scale of the offense, the
district court estimated the amount of cocaine base for which Shinall was responsible
based on the court’s assessment of the evidence. See U.S. Sentencing Guidelines
Manual § 2D1.1 n.12 (1998); United States v. Ayers, 

, 363 (8th Cir.),
cert. denied, 

(1998). Shinall asserts the estimation is wrong because
there was no evidence about the manufacturing of cocaine base from cocaine powder.
Information about manufacturing was unnecessary because the evidence showed
Shinall possessed certain amounts of cocaine base, rather than cocaine powder from

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which cocaine base is made, and the district court added those amounts of cocaine base
to estimate the total amount of cocaine base for which Shinall was responsible. See

. Shinall also contends Horn’s testimony about drug amounts
should be disregarded because she has recanted her testimony. The district court
found, however, that even if the amounts testified about by Horn are not considered,
Shinall’s base offense level would not change given the remaining amount attributable
to Shinall by other evidence. We conclude the district court did not commit clear error
in calculating the total amount of cocaine base attributable to Shinall.

      We thus affirm Shinall’s conviction and sentence for conspiracy to distribute
cocaine base.
.
      A true copy.

             Attest:

                    CLERK, U.S. COURT OF APPEALS, EIGHTH CIRCUIT.




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