United States Court of Appeals
                            FOR THE EIGHTH CIRCUIT
                                  _____________

                                   No. 96-3703
                                  _____________

United States of America,               *
                                        *
             Appellee,                  *
                                        * Appeal from the United States
      v.                                * District Court for the
                                        * Western District of Missouri.
Daryn E. Stewart,                       *
                                        *
             Appellant.                 *
                                  _____________

                                 Submitted: April 18, 1997
                                     Filed: August 20, 1997
                                  _____________

Before McMILLIAN, JOHN R. GIBSON, and BEAM, Circuit Judges.
                           _____________

JOHN R. GIBSON, Circuit Judge.


       Daryn Stewart appeals his convictions for distribution of cocaine base in
violation of 21 U.S.C. §§ 841(a)(1), (b)(1)(A), and (b)(1)(B). He argues that the
district court1 erred in refusing to grant immunity to a witness that Stewart believed
would establish his innocence and in refusing to allow him to cross-examine a police



      1
        The Honorable Dean Whipple, United States District Judge for the Western
District of Missouri.
informant on the informant's involvement in a homicide. Stewart also argues that the
district court erred in sentencing him for selling crack cocaine. We affirm.

       At Stewart's trial the government called Kansas City Police Detective Ray
Staley, who testified that while undercover he bought crack cocaine from Stewart on
three occasions. Staley also testified that Mark Robinson helped him buy crack from
Stewart by calling Stewart and setting up each purchase.

       On cross-examination of Staley, Stewart attempted to show that Robinson had
killed another drug dealer in a drug related shooting before he began cooperating with
the police. Stewart argued to the district court that Robinson faced possible murder
charges for his role in this shooting and was cooperating with the police to avoid those
charges, and that the jury should hear this evidence so they could understand
Robinson's motive to cooperate with the police. The district court excluded all
evidence of Robinson's involvement in the shooting because it was a collateral matter
and because it was inadmissible under Rule 403 of the Federal Rules of Evidence.

       After the government rested its case against Stewart without calling Robinson
as a witness, Stewart attempted to call Robinson to testify about his involvement in the
shooting. The district court, however, refused to allow Stewart to ask Robinson in
front of the jury about the shooting.

       Stewart also attempted to call Eli Strother as a witness. Strother invoked his
Fifth Amendment privilege against self-incrimination, and stated that he would assert
the Fifth Amendment to questions about the case. Stewart asked the district court to
grant immunity to Strother so he could testify for Stewart. The district court refused
to grant Strother immunity, and he did not testify.




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      The jury found Stewart guilty of three counts of distribution of cocaine base.
The district court found that Stewart had sold cocaine base in the form of crack cocaine
and sentenced Stewart accordingly. Stewart appeals his conviction and his sentence.

                                            I.

      Stewart argues that the district court violated his Sixth Amendment right to
confront witnesses against him by preventing him from questioning Staley and
Robinson about Robinson's role in the shooting.

       The Confrontation Clause of the Sixth Amendment guarantees to Stewart the
opportunity for effective cross-examination of witnesses against him, including inquiry
into the witnesses' motivations and biases. See United States v. Warfield, 

, 1024 (8th Cir. 1996), cert. denied, 

(1997). The right to examine
witnesses under the Confrontation Clause is not without limitation. District courts
retain wide latitude under the Confrontation Clause to impose reasonable limits on
cross-examination when they have concerns about harassment, prejudice, confusion of
the issues, a witness's safety, or interrogation that is repetitive or only marginally
relevant. See 

clear abuse of discretion and a showing of prejudice, we
will not reverse a district court's ruling limiting cross-examination of a prosecution
witness on the basis that it impermissibly infringed Stewart's right of confrontation. See

Stewart's argument that the district court erred in preventing him from
cross-examining Staley about Robinson's involvement in the shooting. Stewart wanted
to bring out Robinson's involvement in the shooting to show his bias and strong motive
to cooperate with the police to avoid possible murder charges. Stewart's right to
confront witnesses gives him a right to cross-examine Staley about Staley's motivation
or bias, not Robinson's bias. Cf. Delaware v. Van Arsdall, 

, 678-80
(1986) ("[T]he focus of the Confrontation Clause is on individual witnesses.").

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       Robinson's bias is irrelevant to Staley's testimony. Staley testified that he met
with Stewart on three occasions to buy crack cocaine. Staley stated that at each
meeting Stewart gave him crack cocaine in exchange for money. While Staley testified
that Robinson set up the crack sales and was present at all three sales, Staley's
testimony stands on its own and is unaffected by Robinson's bias. The district court did
not abuse its discretion in preventing Stewart from cross-examining Staley about
Robinson's bias, and there was no violation of the Confrontation Clause.

        We also conclude that the district court did not violate the Confrontation Clause
when it prevented Stewart from calling Robinson to the stand to testify about
Robinson's involvement in the shooting. The Confrontation Clause gives Stewart the
right to cross-examine witnesses against him. The government, however, did not call
Robinson as a witness against Stewart. Therefore, the Confrontation Clause has
nothing to do with the district court's limitation of Stewart's questioning of Robinson.
See Davis v. Alaska, 

, 320 (1974) (stating that the government can avoid
the introduction of bias evidence under the Confrontation Clause by not calling the
witness for whom that evidence is relevant).

                                           II.

      Stewart argues that the district court should have granted Strother immunity so
that Strother could testify in Stewart's defense. Stewart contends that Strother's
testimony was essential to his defense, and that the district court's failure to grant
Strother immunity deprived him of a fair trial. The district court did not have the
authority to grant Strother immunity because this court has consistently refused to
recognize the concept of judicial immunity. See 

. Use
immunity can be granted only when formally requested by the Attorney General, and
the district court is without power to force the government to grant a witness immunity.
See 

district court was completely without power to grant Strother
immunity and correctly refused to do so.

                                          -4-
                                           III.

       Stewart argues that the district court erred in sentencing him to the enhanced
penalties for selling crack cocaine because there is no evidence to support the district
court's factual finding that he sold crack cocaine.

       Stewart should receive the enhanced penalties contained in the Sentencing
Guidelines only if the district court properly found that Stewart distributed the "crack"
form of cocaine base. See U.S.S.G. § 2D1.1(c), Note (D); United States v. Munoz-
Realpe, 

, 377 (11th Cir. 1994). The sentencing judge also presided at
Stewart's trial. See United States v. Wiggins, 

, 178 (8th Cir. 1997). We
can reverse the district court's factual finding only if it is clearly erroneous. See United
States v. Williams, 

, 243 (8th Cir. 1996).

       There is evidence in the record to support the district court's factual finding.
Staley testified at trial that he bought crack cocaine from Stewart on three occasions.
Staley also identified the crack cocaine he bought from Stewart when the government
introduced it into evidence. The government had the cocaine analyzed by a chemist
and entered the chemist's reports into evidence at Stewart's trial. The reports state that
the cocaine base was "rock-like." We conclude that the district court's finding that
Stewart sold crack cocaine is not clearly erroneous.

       Stewart argues that there must be evidence that the cocaine base that he sold
contained cocaine hydrochloride and sodium bicarbonate before the district court may
find that the cocaine base is crack cocaine. We reject Stewart's argument because the
Sentencing Guidelines only state that crack cocaine is "usually prepared by processing
cocaine hydrochloride and sodium bicarbonate." U.S.S.G. § 2D1.1(c), Note (D). This
language does not require such evidence before the district court can conclude that a
substance is crack cocaine, and such evidence was not required in this case.


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We affirm Stewart's conviction and sentence.

A true copy.

      Attest:

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




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