                         United States Court of Appeals
                            FOR THE EIGHTH CIRCUIT
      ___________

       No. 97-1021
      ___________

United States of America,              *
                                       *
             Plaintiff - Appellee,     *
                                       *
      v.                               *
                                       *
Brian Dierling,                        *
                                       *
           Defendant - Appellant.      *
      ___________
                                           Appeals from the United States District
       No. 97-1023                         Court for the Eastern District of Missouri.
      ___________

United States of America,              *
                                       *
             Plaintiff - Appellee,     *
                                       *
      v.                               *
                                       *
Mark Perkins,                          *
                                       *
             Defendant - Appellant.    *
      ___________

       No. 97-1024
      ___________

United States of America,               *
                                        *
            Plaintiff - Appellee,       *
                                        *
      v.                                *
                                        *
Louis Younger,                          *
                                        *
           Defendant - Appellant.       *
      ___________

       No. 97-1026
      ___________

United States of America,               *
                                        *
             Plaintiff - Appellee,      *
                                        *
      v.                                *
                                        *
Arthur Holt, also known as Artie,       *
                                        *
             Defendant - Appellant.     *
                                   ___________

                             Submitted: September 11, 1997
                                 Filed:
                                  ___________

Before HANSEN, ROSS, and MURPHY, Circuit Judges.
                           ___________

                                       -2-
MURPHY, Circuit Judge.


       Appellants Brian Dierling, Louis Younger, Arthur Holt, and Mark Perkins appeal
their convictions and sentences for conspiracy to manufacture, distribute, and possess
with intent to distribute methamphetamine in violation of 21 U.S.C. § 846. They seek
a new trial or resentencing because of claimed errors, including improper admission of
evidence, a joint trial, failure of the district court1 to provide immunity to their
witnesses and of the government to furnish Brady material, and several sentencing
issues. We affirm.

                                           I.

       A one count indictment charged appellants with a conspiracy to manufacture and
distribute methamphetamine in Missouri and Illinois. There was evidence at trial that
Dierling, Younger, and Holt were manufacturing methamphetamine in a clandestine
laboratory on Dierling’s property and that they and Perkins were distributing the drug
to unindicted coconspirators for resale and also directly to users. Dierling oversaw the
manufacturing operations, the procurement of materials for the laboratory, and the drug
distribution. Younger was Dierling’s partner and held recipes for manufacturing
methamphetamine. The involvement of Holt and Perkins was less important, but each
sold methamphetamine to dealers and users and each picked up drugs and dropped off
money at Dierling’s property. Holt also assisted in the manufacturing operations.

       There were a number of sources of evidence about the conspiracy, including
detailed testimony from associates. Bobby Collis testified that Dierling told him he was
making methamphetamine in one pound blocks, that Arthur Holt was “moving crank



      1
        The Honorable Carol E. Jackson, United States District Judge for the Eastern
District of Missouri.

                                          -3-
for him,” and that Holt had been arrested with his drugs. Cindy Craig, who lived with
Younger, testified that he told her that he and Dierling made and sold drugs together,
that he showed her as many as ten recipes for making methamphetamine, and that he
described to her their manufacturing operations and the quality of the drugs they were
making. She once went to Dierling’s house with Younger and saw conspirators
packaging and weighing drugs in the bedroom.

       Stephanie Nickell reported that she had seen Dierling, Younger, and Danny
Craig cooking methamphetamine at Dierling’s house and had observed cantaloupe-
sized quantities of methamphetamine at Younger’s residence during the period she was
selling drugs for him. She helped Dierling, Holt, and Younger package
methamphetamine and took some to sell herself. Craig told her that he was also selling
methamphetamine for Dierling. Nickell bought items for the methamphetamine lab for
Younger and Dierling. Dierling gave her a handgun for her protection because drug
dealers in the area were selling poor quality methamphetamine and attributing it to him;
he feared reprisals.

       Candy True testified that Younger delivered drugs to an unindicted coconspirator
for resale and that she went with him to Dierling’s farm where he picked up
methamphetamine. She testified that on another occasion she went to the farm with
Perkins, Holt, and Holt’s daughter; Holt went into the barn to get methamphetamine.
 She also saw Younger, Holt and Perkins all deliver drugs on separate occasions to a
coconspirator who would resell them.

       Michelle Crawford testified that she sold ten “eight balls” of methamphetamine
on a daily basis for Holt, whose source was Dierling. She saw Dierling deliver a six-
inch wide, four-inch tall amount of methamphetamine to Holt. In October of 1994 she
went to an apartment with Holt where she saw Dierling with some ten pounds of
methamphetamine, money, and guns. Holt took methamphetamine from the apartment
and in return left three envelopes which contained money she had previously counted.

                                          -4-
Between October of 1994 and May of 1995, Crawford, Holt and/or Perkins made
approximately 10 trips to Dierling’s farm and obtained at least five pounds of
methamphetamine on each trip, which they would package in smaller quantities for
distribution. Holt and Perkins also went once or twice a week without her to get drugs
from Dierling.

       George Heller testified that Younger took him to Dierling’s property to tow a
car, and he saw Holt and Dierling there with guns and radios and noticed the area
smelled like chemicals. He overheard Holt tell Younger that “[i]f anything goes wrong,
we’ll know who brought them here.”

      Law enforcement officers also obtained evidence about the existence of the
conspiracy. Missouri state troopers twice arrested Perkins and Holt, seizing over
$11,000 cash, weapons and methamphetamine.2 An undercover officer purchased
methamphetamine from Holt on one occasion and discussed with him the resale of the
drugs and the fact that he might need more later. A search of Holt’s home revealed
digital scales, plastic baggies, and drug notes. Police also seized methamphetamine
from Holt’s car and over $2,800 cash from his person when they responded to a
disturbance call at a bar. A deputy sheriff arrested Dierling and removed
approximately $1,100 cash, methamphetamine, and syringes from him. Officers from
the Putnam County sheriff’s department seized syringes and methamphetamine during
a search of Younger’s home, and officers saw materials commonly used in
methamphetamine laboratories in Dierling’s barn when they went to his property to
answer a domestic dispute call.

       Appellants were found guilty after a two and a half week jury trial. The district
court then received additional evidence at a sentencing hearing and found that the


      2
       Both Holt and Perkins told Michelle Crawford they had been carrying drugs for
Dierling when they were arrested.

                                          -5-
conspiracy involved 10 to 30 kilograms of methamphetamine and applied four level
sentence enhancements to Dierling and Younger for their roles in the conspiracy and
two separate enhancements to Dierling for obstruction of justice. Dierling and Younger
were sentenced to life imprisonment, Holt to 360 months, and Perkins to 235 months.

       Appellants argue on appeal that they are entitled to a new trial because the court
admitted inflammatory evidence about acts that were neither foreseeable nor in
furtherance of the conspiracy, refused to sever their cases despite the risk that evidence
of unrelated acts by coconspirators would improperly influence the jury, and refused to
provide judicial immunity for their witnesses. They also rely on the government’s
alleged failure to disclose material required by Brady v. Maryland, 373 U.S. 83 (1963),
and they contend that the court improperly considered unreliable testimony in
calculating the amount of drugs involved in the conspiracy. Finally, Dierling challenges
the enhancements for his leadership role and for obstruction of justice.

                                           II.

                                           A.

       All appellants claim they are entitled to a new trial because of inflammatory
evidence they view as unrelated to the conspiracy. They say they were unfairly
prejudiced by evidence of the killing of Danny Craig, the burning of Dierling’s barn, the
shooting of a deputy sheriff, and the discovery of a cache of weapons on Dierling’s
property.

       The government contends that the evidence about the killing was directly related
to the conspiracy because Dierling and Younger killed Craig, a coconspirator, over a
drug debt he owed Dierling. Craig was a heavy methamphetamine user, and he
participated in the conspiracy’s manufacturing operations, packaged methamphetamine
for sale, and dealt drugs for Dierling. In late May or early June of 1995, Craig took a

                                           -6-
weekend trip for the purpose of selling drugs, but used them himself instead. Craig later
told government witness Candy True that Dierling was upset with him and that he owed
Dierling drugs and money. Michelle Crawford testified that soon thereafter Perkins and
Holt administered a severe beating to Craig, explaining to him that “Brian said you
shouldn't have did what you did.”

       Stephanie Nickell testified that in the spring of 1995, Dierling told her he had
placed a contract for $10,000 on Craig’s life, and on June 9 he and Younger asked her
to take them to Craig. She led them to a party attended by Craig where Dierling yelled
that Craig had his money. Dierling ordered Craig to drive out to his house with Nickell;
Dierling and Younger followed. At Dierling’s house Nickell saw Younger and Dierling
prod Craig into a utility room near the living room. She heard Craig scream and then
two gunshots. Younger came out of the utility room and asked her for the keys to her
vehicle. She went outside with him and saw Craig lying motionless in the back of her
truck with gunshot wounds in his chest. Dierling, Younger, and Nickell then drove in
the truck to Younger’s house. On the way Dierling indicated that Craig would not be
ripping off anyone any more. Once on Younger’s property, Younger and Dierling
pulled Craig from the truck and got a knife out of it. Nickell heard chopping sounds and
then saw Dierling hold up Craig’s severed head by the hair. Younger threatened that
he would do the same thing to her if she crossed him. The three then drove back to
Dierling’s property after stopping to show the head to an acquaintance, Jess Mahurin.
Dierling drove off in Younger’s car, and Younger and Nickell continued on to a friend’s
house in her truck, stopping at a car wash along the way to clean the bed of the pickup.



      The government also presented evidence that Dierling burned his barn and house
to conceal evidence of the conspiracy. A police officer testified that he went to
Dierling’s home on July 15, 1995, in response to a domestic dispute call, and saw
materials commonly used to manufacture methamphetamine in the barn. A week later,
a neighbor noticed Dierling drive up his driveway, remain there briefly, and then leave

                                          -7-
shortly before his house and barn were seen to be on fire. An investigator from the
Missouri Division of Fire Safety concluded that the fire had been set intentionally, but
could not say who started the blaze. Police arrested Dierling in connection with the
arson on the following day and seized $1,100 and some methamphetamine from his
person. Bobby Collis testified that while they were in jail together Dierling admitted
to him that he had set the fire in order to destroy parts of a methamphetamine laboratory
he could not move.

       Appellants also challenge the admission of evidence of a high speed car chase
involving Dierling and Adair County deputy sheriff Leonard Clark, as well as evidence
that Dierling shot Clark and had a variety of weapons on his property. Dierling fled
when Clark attempted to stop and arrest him for violation of a protection order. A chase
ensued which ended in Dierling’s shooting and wounding Clark (Dierling was in turn
shot by Clark.).

                                           B.

       We review the trial court’s evidentiary rulings for abuse of discretion, keeping
in mind that its discretion is particularly broad in a conspiracy trial. United States v.
Searing, 984 F.2d 960, 965 (8th Cir. 1993). In order to establish the existence of a
conspiracy the government must prove that at least two persons entered into an
agreement with an objective to violate the law. United States v. Wilson, 103 F.3d 1402,
1406 (8th Cir. 1997). Acts committed in furtherance of a conspiracy are admissible as
circumstantial evidence that the agreement existed, Blumenthal v. United States, 88 F.2d
522, 531 (8th Cir. 1937), unless the evidence causes “unfair prejudice, substantially
outweighing probative value” under Fed. R. Evid. 403. See United States v. McRae,
593 F.2d 700, 707 (5th Cir. 1979). The critical issue is “the degree of unfairness of the
prejudicial evidence and whether it tends to support a decision on an improper basis.”
United States v. Payne, 119 F.3d 637, 645 (8th Cir.), cert. denied, No. 97-6358, 1997
WL 644822 (U.S. Nov. 17, 1997).

                                          -8-
       The record indicates that the killing of Danny Craig was admissible evidence of
an act committed in furtherance of the conspiracy and therefore relevant and not unfairly
prejudicial to the appellants. Craig was actively involved in the conspiracy, and his
elimination resulted from his drug debt to Dierling. The slaying was an act by the
conspiracy’s leaders to control a subordinate member of the conspiracy. See Untied
States v. Tramunti, 513 F.2d 1087, 1118 (2d Cir. 1975). The evidence showed the
lengths the conspirators would go to protect their interest in the long term viability of
the conspiracy. See United States v. Meester, 762 F.2d 867, 874 (11th Cir. 1985). It
also demonstrated concerted drug-related action by all conspirators. Holt and Perkins
caught and beat Craig and told him Dierling was upset. Dierling and Younger
committed the actual killing in Dierling’s home, the center of the operation. The
evidence was probative of a conspiracy involving all appellants.

       Appellants question the sufficiency of the evidence that the killing actually
occurred. Craig’s body was never found, and the only direct evidence at trial about the
killing was the eyewitness testimony of Stephanie Nickell. The evidence and the
credibility of the witnesses were for the jury to weigh, however, and Nickell was
thoroughly cross-examined.3 There was also corroboration of her testimony by evidence
about Craig’s disappearance and the evidence supplied by Michelle Crawford
suggesting Perkins and Holt beat Craig as part of Dierling’s retaliation against him.
Although the slaying evidence was violent and grisly in nature, there was testimony to
connect it directly to the drug business of which appellants were accused. Craig took
Dierling’s drugs and didn’t pay him, and brutal consequences followed to enforce the
rules of the business. The district court did not abuse its discretion in determining that
the probative value of the slaying evidence outweighed any prejudicial effect.



      3
       Nickell did not approach authorities with the information she possessed, but
revealed it in the course of questioning after jailers heard her screaming during
nightmares she had in jail. The sheriff testified that after he took her to the jail doctor
she mentioned the Craig killing.

                                           -9-
       Appellants also object to the evidence related to the burning of Dierling’s barn and
house on the grounds there was no proof Dierling was responsible or that the burnings
were linked to the conspiracy. They claim that the fires were related to Dierling’s marital
problems and pending divorce from his wife who lived on the property. Younger, Perkins,
and Holt argue that the evidence was especially prejudicial to them since they could not
have foreseen the fire. The evidence linking the fire to Dierling and the methamphetamine
operation was sufficient to find that it was an act to protect the conspiracy. The fire
followed the visit of law enforcement officers who were thus able to see incriminating
evidence. It was not unforeseeable to the coconspirators that Dierling would take steps
to eliminate the evidence, and Collis testified that Dierling told him he had set the fire for
that purpose. The district court did not abuse its discretion in admitting this evidence.

        Appellants claim that Dierling’s flight from deputy Clark when he attempted to stop
him and the subsequent shooting of Clark were not in furtherance of the conspiracy
because Clark intended to arrest Dierling for violating a domestic protection order. Flight
from law enforcement officers can be probative of consciousness of guilt and may further
a conspiracy. See United States v. Roy, 843 F.2d 305, 310 (8th Cir. 1988). The intended
purpose of the attempted stop need not be related to the conspiracy. Id. The real question
is what is in the mind of the person who flees and whether there is sufficient evidence to
allow the inference that the flight was prompted by consciousness of guilt. Id. There was
evidence that Dierling was on a drug-related errand when Clark attempted to stop him and
that Dierling was aware that the authorities knew about his drug activities. The jury could
have determined that the high-speed flight was intended to protect and maintain the
conspiracy, and this was not the only evidence it heard about flight by a conspirator.
Dierling had evaded capture by the police on an earlier occasion while on his way to buy
methamphetamine production materials. Younger was involved in two high-speed
pursuits after he refused to pull over his motorcycle when police attempted to stop him for
traffic




                                           -10-
violations.4 There was also evidence that Dierling made statements indicating his
willingness to harm law enforcement officers in order to protect his drug activities. The
evidence of the chase and shooting of Clark was relevant to the conspiracy, and the court
minimized any unfair prejudice to other conspirators by instructing the jury that it should
consider the shooting only against Dierling.

       Younger and Perkins challenge the admission of evidence of a large cache of
weapons seized from Dierling’s home and argue there was no showing that the guns and
knives were related to the conspiracy. Weapons are key tools in the drug trade and can
be evidence of a drug conspiracy. See United States v. Emmanuel, 112 F.3d 977, 979-80
(8th Cir. 1997). Weapons played a significant role in this conspiracy. Police recovered
a military-style assault rifle from Dierling’s truck, along with cash and methamphetamine,
when he was arrested for arson. Dierling shot deputy Clark with a .357 caliber handgun,
and he apparently became associated with Younger after he shot him by accident when
aiming at his drug associate. The weapons were relevant to the conspiracy charge and not
unfairly prejudicial in light of all the evidence of the operations of the conspirators.

      Finally, Dierling’s argument that the evidence about the slaying, fire, and shooting
was inadmissible other crimes evidence under Fed. R. Evid. 404(b) is incorrect. This was
evidence tending to show that a conspiracy existed among the appellants and how it
operated. “Direct evidence of participation in a conspiracy is probative of the crime
charged and thus does not constitute other crimes evidence within the meaning of rule
404(b).” United States v. Kinshaw, 71 F.3d 268, 270 (8th Cir. 1995).




      4
        Younger was returning from a drug deal when the first chase occurred, and the
police recovered $2100.00 cash, methamphetamine, and syringes; he was on his way
to sell drugs the next time, and knives, a scale, and drugs were found on him.

                                         -11-
                                             III.

                                             A.

       Younger argues that his conviction should be reversed because the trial court refused
to provide immunity for his witnesses. Younger attempted to call Shawn Russell and Jess
Mahurin who both refused to testify after the court appointed counsel for them and they were
advised of their fifth amendment rights. Younger asked the court to grant immunity to the
witnesses or require the government to offer it, but the court declined. Younger claims that
since the prosecution relied on immunized witnesses to present its case and his witnesses
would have offered exculpatory testimony, the court’s refusal to offer immunity violated his
rights under the compulsory process clause of the sixth amendment. Younger speculates that
Russell would have testified that he had seen Danny Craig alive after the alleged killing and
that Stephanie Nickell had lied. He also says that Mahurin would have denied ever seeing
Craig’s severed head or seeing Dierling, Younger, or Nickell on the night of the killing.

       Younger had no right to judicially imposed immunity for his witnesses. No power or
duty to grant judicial immunity has been recognized in this circuit. United States v. Robaina,
39 F.3d 858, 863 (8th Cir. 1994); United States v. Hardrich, 707 F.2d 992, 994 (8th Cir.
1983). Use immunity has been ordered elsewhere on occasion for a witness with “clearly
exculpatory” evidence where there is no strong countervailing interest of the government.
Gov’t of the Virgin Islands v. Smith, 615 F.2d 964, 972-73 (3d Cir. 1980). There is no
reason in this case to examine the policy implications of judicial involvement in use
immunity, see, e.g., United States v. Capozzi, 883 F.2d 608, 613-614 (8th Cir. 1989); United
States v. Turkish, 623 F.2d 769 (2d Cir. 1980), because Younger has not shown that the
proposed testimony was clearly exculpatory. There was enough evidence to convict the
appellants of conspiracy without evidence of the killing, and there was no deliberate
distortion of the truth-finding process by the government, and no government misconduct or
threats to




                                          -12-
witnesses. The court did not err in declining to grant judicial immunity to Younger’s
witnesses.5

                                             B.

       Younger objects to exclusion of testimony by his investigator about statements made
by Mahurin and Russell in interviews. The testimony was excluded by the trial court on the
grounds it was hearsay and the witnesses were not unavailable within the meaning of Fed.
R. Evid. 804(b)(3) and 804(b)(5). The government concedes the witnesses were unavailable
because of their assertion of the fifth amendment, but it argues the evidence is inadmissible
under either exception because both rules require trustworthiness. The trial court did not
make a specific reliability determination, but both 804(b)(3) and 804(b)(5) permit the
admission of evidence from an unavailable witness only if it has indicia of trustworthiness.
The trustworthiness requirement was not satisfied here, and there was therefore no error in
exclusion of the testimony. See United States v. Thomas, 919 F.2d 495, 498 (8th Cir. 1991).
Moreover, the statements which Younger claims Russell or Mahurin would make would not
have subjected them to criminal liability, a requirement under Rule 804(b)(3), United States
v. Hazelett, 32 F.3d 1313, 1317-18 (8th Cir. 1994), and Rule 804(b)(5) is applicable only
in exceptional circumstances not present here. United States v. Gaines, 969 F.2d 692, 697
(8th Cir. 1992).

                                             C.

      Perkins argues that the court abused its discretion by refusing to allow him to impeach
government witness Michelle Crawford by introducing an interview report of a DEA agent.
According to this report Crawford told the agent that she saw Perkins




      5
      Younger additionally sought court-imposed immunity for Paul Smith and Debbie
Bramlett, but their testimony was also not clearly exculpatory.

                                         -13-
beat Danny Craig, cut him with a large knife, and throw him into a ditch. She also said that
Perkins had intimated to her that he had fed Craig’s body to some hogs. Counsel for Perkins
questioned Crawford at trial about her interview but did not ask her about the hog statement
or attempt to introduce the contents of the report against her. Instead, Perkins offered the
report during the testimony of the DEA agent in order to impeach Crawford’s testimony.
The court did not err in refusing to admit the report. Rule 613(b) allows impeachment by
prior inconsistent statement only when a witness is first provided an opportunity to explain
the statement. See United States v. Sutton, 41 F.3d 1257, 1260 (8th Cir. 1994). Moreover,
the statement was not inconsistent with Crawford’s testimony, see United States v. Hale, 422
U.S. 171, 176 (1975); United States v. Cody, 114 F.3d 772, 776 (8th Cir. 1997), and the
court invited Perkins to offer the statement in his case-in-chief, but he declined.

                                               IV.

       Holt challenges the failure of the trial court to give a special instruction to the jury on
how the government witnesses interpreted their immunity agreements. He argues that the
witnesses’ testimony about immunity differed from the wording of their agreements and that
an instruction was therefore necessary. Appellants questioned the witnesses about their
agreements at trial, and they were free to argue to the jury about the agreements, how the
witnesses interpreted them, and credibility. Instructions 5 through 17 explained to the jury
the factors it should consider in evaluating credibility. The immunity agreements, prior
convictions, and government payments for assistance were included in the explanation.
There was no need to give an additional instruction in these circumstances. See United
States v. Ridinger, 805 F.2d 818, 821 (8th Cir. 1986); United States v. Bowman, 798 F.2d
333, 336 (8th Cir. 1986).




                                           -14-
                                             V.

       Younger, Holt, and Perkins contend it was reversible error not to sever their cases
from that of Dierling because there was evidence admitted at their joint trial concerning his
independent criminal activity, causing the jury to find them guilty because of their
association with him. Holt adds that he was entitled to a severance because of evidence of
acts that were not foreseeable to him or committed in furtherance of the conspiracy and that
would not have been admissible if he had been tried alone.

       Only an abuse of discretion resulting in definite prejudice requires reversal of a
conviction based on denial of a motion to sever. United States v. Delpit, 94 F.3d 1134, 1143
(8th Cir. 1996). A joint trial is appropriate for those charged with conspiracy where proof
of the charges is based on common evidence and acts. United States v. Stephenson, 924
F.2d 753, 761 (8th Cir. 1991) (quoting United States v. Jackson, 549 F.2d 517, 523 (8th Cir.
1977)); see also United States v. Kindle, 925 F.2d 272, 277 (8th Cir. 1991). Where there
are multiple criminal acts in furtherance of a conspiracy, each defendant need not have
participated in every act for a joint trial to be appropriate. Delpit, 94 F.3d at 1143; United
States v. Jones, 880 F.2d 55, 62-63 (8th Cir. 1989). It does not matter that there may be
varying strength in the evidence against each defendant. Stephenson, 924 F.2d at 761
(quoting Jackson, 549 F.2d at 525). In order to prevail appellants must establish either that
a specific trial right was prejudiced or that a joint trial prevented the jury from making “a
reliable judgment about guilt or innocence.” Zafiro v. United States, 506 U.S. 534, 539
(1993).

       It was appropriate to try appellants together. There was evidence that the challenged
acts were committed in furtherance of the conspiracy so they would have been admissible
in individual trials. See United States v. Darden, 70 F.3d 1507, 1527 (8th Cir. 1995), cert.
denied, 116 S.Ct. 1449 (1996). The other conspirators were also




                                          -15-
closely involved in events described in the challenged evidence. All of them committed
some act of violence against Craig related to the drug debt he owed Dierling, and a joint trial
is permissible even if all conspirators did not participate in a killing where violence is a
modus operandi of a conspiracy and the action was committed in furtherance of the
conspiracy. See Delpit, 94 F.3d at 1143. All conspirators were involved in flights from law
enforcement except Perkins,6 and it cannot be said that the chase evidence prevented the jury
from making an individual determination of whether a particular defendant participated in
the conspiracy. All took part in drug-related activities on Dierling’s property, and it would
have been foreseeable that Dierling might attempt to prevent detection of evidence there.
All carried firearms during the conspiracy, and the court instructed the jury to consider the
shooting of deputy Clark only against Dierling and to make individual determinations of guilt
or innocence as to each defendant. The evidence was not so complicated that the jury would
have been unable to make individual determinations about the guilt or innocence of each
defendant. United States v. Willis, 940 F.2d 1136, 1138 (8th Cir. 1991). A joint trial was
necessary to give the jurors a perspective on all the evidence. Delpit, 94 F.3d at 1143
(quoting Darden 70 F.3d at 1528). The court did not err in denying the motions to sever.

                                             VI.

      Younger and Perkins argue they are entitled to a new trial because of the
government’s failure to turn over Brady material. After his conviction Younger moved for
a new trial based on newly discovered evidence. He claimed the government should have
given him information it had about Judy Dierling, Brian’s wife at the time




      6
       Dierling and Younger led chases more than once in their vehicles, and Holt was
a passenger during Dierling’s first chase.

                                          -16-
of the conspiracy, and about a DEA interview with Danny Collis, the nephew of Bobby
Collis.7 The district court denied the motion after a hearing.




      7
       Dierling claims to have discovered other new evidence during the pendency of
this appeal and moved for a remand for it to be considered by the district court. The
other appellants have joined in the motion.

        Appellants claim this evidence shows that Craig was killed on a different date
from Nickell’s account and that there was an additional investigation into the killing.
They rely on two search warrant affidavits. One indicates that Craig was reported
missing on May 25, 1995, several weeks before his alleged murder on June 9, 1995.
The other states that three of Craig’s acquaintances were among the last to see him
alive, that people were splitting up Craig’s things because they thought he was dead,
and that the police had received tips to search a certain pond for Craig’s remains. This
affidavit also reports that one of the individuals said that “Danny Craig wouldn't be
coming back, that Super Bee, Brian Dierling had got him.” Appellants claim this
information should have been disclosed under Brady.

       Appellants have not made a sufficient showing to require a remand, and their
motion is denied. At the time of trial appellants had a police report stating that Danny
Craig had been last seen on May 23, 1995, two days before the Schuyler County
affidavit says Craig was reported missing. The government points out that appellants
had been aware that there were local investigations into Craig’s slaying and showed it
during their cross examination of Bobby Collis. The allegedly new evidence also
would be of questionable value to the defense.

        Dierling has filed several pro se briefs discussing other information that has come
to his attention, a self-styled “motion submitting facts,” and a request that he be
furnished with his own copy of the trial transcript at government expense. It is not our
practice to consider pro se briefs filed by parties represented by counsel, Howard v.
Caspari, 99 F.3d 895, 898 (8th Cir. 1996), cert. denied, 117 S.Ct. 1831 (1997), and
based on our review of his submissions, there is no reason to depart from the practice
in this instance, and his counsel has cited the transcript extensively.

                                           -17-
       The government violates a defendant’s right to due process when it fails to disclose
to the defense favorable material evidence in its possession. Brady v. Maryland, 373 U.S.
83 (1963). Evidence is material when there is a reasonable probability that the result of the
trial would have been different had the government disclosed the information. Kyles v.
Whitely, 115 S.Ct. 1555, 1566 (1995). A “reasonable probability” of a different result is
shown when nondisclosure “undermines the confidence in the outcome of the trial.” Id.
(quoting United States v. Bagley, 473 U.S. 667, 678 (1985)).

        Appellants rely on an affidavit of Judy Dierling’s attorney in which he states that he
heard Judy tell a DEA agent over the phone that she had no knowledge of a
methamphetamine laboratory on the Dierling property or Craig’s having been killed there.
They say the government had a duty to disclose this information under Brady, as well as the
fact that it had been able to locate Judy and place her under subpoena. They argue that they
would then have called Judy to testify and that her testimony would have impeached
Stephanie Nickell who had reported that Judy was also in the house the night Craig was
killed.

      A variety of witnesses at trial testified to the extent and nature of the conspiracy, and
evidence provided by law enforcement of drug dealing and seized drugs, money, and
weapons was introduced. Appellants also conducted a thorough cross examination of
Nickell, questioning her about prior inconsistent statements, lies told to the police, and drug
use. Judy Dierling was originally charged in state court with the murder of Danny Craig
along with Brian Dierling and Younger, but the charges against her had been dismissed. Her
statement to the agent was obviously in her interest since it was exculpatory to her.
Considering the nature of Judy’s possible testimony, the evidence tending to corroborate
Nickell’s story, and especially the fact that the government’s case against appellants did not
depend on Nickell’s testimony, it is not reasonably probable that Judy’s testimony would
have altered the outcome of the trial. The




                                          -18-
information was thus not material. Bagley, 473 U.S. at 682; United States v. Risken, 788
F.2d 1361, 1375 (8th Cir. 1986).

       Appellants were aware that Judy Dierling had lived on Dierling’s property, that she
had been initially charged with the murder of Craig, that she had pled not guilty to the
charge, and that those charges had been dismissed. The evidence they say the government
should have disclosed adds little, if anything, to what they already knew. They did not
inform the government they were looking for Judy Dierling or request its assistance in
locating her or in securing her testimony. There is no indication that the government sought
to hide her or make her unavailable or that it suppressed material information. See United
States v. Cheatham, 899 F.2d 747, 753 (8th Cir. 1990); United States v. Ruggiero, 472 F.2d.
599 (2d Cir. 1973). In these circumstances neither Brady nor the compulsory process clause
of the sixth amendment were violated.

       Appellants also claim they were entitled to statements Danny Collis made to DEA
agents during a pretrial interview because their investigator Wesley Burns allegedly
discovered that Collis had given exculpatory information. At a hearing on the motion for a
new trial, Burns testified that Collis had claimed to him that he had “first hand knowledge”
about what happened to Danny Craig and that Younger and Dierling had nothing to do with
it. The statements Collis made to Burns do not indicate that he gave this information to the
government, however, and the district court did not so find.8 Mere speculation that the
government had exculpatory evidence is an insufficient basis for a Brady claim, United
States v. Van Brocklin, 115 F.3d 587, 594 (8th Cir. 1997), and the government has no duty
to disclose information it does not have. Reed v. United States, 106 F.3d 231, 235 (8th Cir.
1997).




      8
        We have reviewed the tape of the interview between Burns and Collis. During
the interview Collis responded affirmatively to a series of leading questions from the
investigator, but he did not make any statements of his own about the killing and did
not say anything about having reported such information to the government.

                                         -19-
      The district court did not err in denying the motion for a new trial on the ground that
favorable material information was not disclosed by the government.

                                             VII.

       All appellants claim that they are entitled to resentencing. They say the court used
unreliable testimony to determine that the conspiracy involved 10 to 30 kilograms of
methamphetamine. Younger also argues that it was error to include in that amount a
container of methamphetamine which he claims was unmarketable. In addition, Dierling
challenges the enhancements he received for being a leader of the conspiracy and for
obstruction of justice. The amount of drugs must be established by a preponderance of the
evidence, United States v. Rose, 8 F.3d 7, 9 (8th Cir. 1993), and we review sentencing
findings for clear error. United States v. McMurray, 34 F.3d 1405, 1415 (8th Cir. 1994).

                                              A.

      Appellants object to the court’s reliance on testimony by three immunized witnesses
who were admitted drug addicts. The sentencing guidelines provide that “[w]here there is
no drug seizure or the amount seized does not reflect the scale of the offense, the court shall
approximate the quantity of the controlled substance.” USSG § 2D1.1, comment. (n.12).
In such situations it is proper to rely on testimony of witnesses to establish drug amounts.
See United States v. Marks, 38 F.3d 1009, 1014 (8th Cir. 1994). The sentencing court’s
assessment of the credibility of witnesses is nearly unreviewable. United States v. Karam,
37 F.3d 1280, 1286 (8th Cir. 1994). Appellants’ expert pharmacologist testified at the
sentencing hearing that users can suffer hallucinations which could distort their estimates of
drug quantities, and they rely on United States v. Simmons, 964 F.2d 763, 776 (8th Cir.
1992), where the key witness lied under oath and also admitted that her drug use had
impaired her memory. The circumstances here are different from Simmons. Two of the
government witnesses




                                          -20-
admitted that while under the influence of methamphetamine they had experienced
paranoia or “paranoia-like hallucinations,” but there was no demonstrated untruthfulness
and nothing in the record to indicate that they had suffered memory loss or hallucinated
about the amount of drugs they saw. Appellants also argue that the witnesses were
unreliable because the prices they reported did not always fit the amounts of
methamphetamine. One witness reported that Holt and Perkins bought five pound
quantities of methamphetamine from Dierling and Younger for $5,000, but trial
testimony established that five pounds had a street value of $160,000. There was
testimony, however, that appellants had gone to Dierling’s farm on several occasions to
deliver money for previously received drugs. The court could have found that partial
payments were made or that Holt and Perkins paid reduced rates because of their
position in the conspiracy. It was up to the court to evaluate the testimony, and its
findings were not clearly erroneous.

                                          B.

       Younger argues that the court erred by partially basing his sentence on 300 grams
of a substance containing methamphetamine that was found in a jar seized during a stop
of his vehicle and on other seized substances containing methamphetamine. Younger
contends that these substances were only 0.5% methamphetamine and were therefore
undistributable or unmarketable under United States v. Jennings, 945 F.2d 129 (6th Cir.
1991), amended on other grounds, 966 F.2d 184 (6th Cir. 1992), cert. denied, 117 S.Ct.
411 (1996), and United States v. Jackson, 115 F.3d 843 (11th Cir. 1997). The
methamphetamine in Jennings likely contained uningestible, poisonous byproducts, and
Jackson held that only “usable” or “marketable” amounts of controlled substances
should be counted for sentencing. 115 F.3d at 846-48. Appellants have not presented
evidence that the contents of the jar9 or any of the methamphetamine

      9
       Although Younger argued at his sentencing hearing that the jar contained waste
water left over from the manufacture of methamphetamine, he does not make that
argument on appeal. Subsequent to Jennings, the United States Sentencing

                                         -21-
introduced at trial was tainted or unmarketable, however.10 The guidelines specify that
the “weight of a controlled substance set forth in the table refers to the entire weight of
any mixture or substance containing a detectable amount of the controlled substance.”
USSG § 2D1.1 (c). (n.*) (Drug Quantity Table). Since 0.5% is a detectable amount, the
guidelines require that the drug calculations include the methamphetamine Younger
challenges. See United States v. Smith, 49 F.3d 362, 367 (8th Cir.) (plain meaning of
the guidelines is controlling), cert. denied, 514 U.S. 1131 (1995).

       Dierling argues in addition that the court erred in including in its count amounts
that could have been manufactured from a recipe that he gave to Bobby Collis while they
were in jail. Dierling contends the recipe would not have yielded methamphetamine, but
the government presented evidence to the contrary and it was for the trial court to
resolve any conflict. See, e.g., United States v. Carter, 997 F.2d 459, 460-61 (8th Cir.
1993).

                                            C.

       Dierling also challenges his sentence enhancements: four levels because he was
a leader or organizer of an enterprise involving five or more participants, USSG § 3B1.1,
and another four levels for obstruction of justice for burning his property and for his
flight from law enforcement. USSG § 3C1.1. The trial court examines all relevant
conduct in the case to determine an individual’s role in the charged offense,




Commission amended the commentary to the guidelines to specify that “waste water
from an illicit laboratory used to manufacture a controlled substance” does not count
towards sentencing. USSG § 2D1.1, comment. (n.1).
      10
        It is therefore not necessary to consider whether the marketability test should
apply in this circuit.

                                          -22-
Untied States v. Flores, 959 F.2d 83, 86 (8th Cir. 1992), and its findings are reviewed
under the clearly erroneous standard. United States v. Skorniak, 59 F.3d 750, 757 (8th
Cir.), cert. denied, 116 S.Ct. 487 (1995).

       There was ample evidence to show that Dierling was a leader and organizer of a
methamphetamine manufacturing and distribution conspiracy involving five or more
people. USSG § 3B1.1(a). Dierling’s participation in the conspiracy conforms in many
respects to the types of activity described in the commentary to the relevant guideline
section. USSG § 3B1.1, comment. (n.4). Dierling exercised decision making authority
for the conspiracy as a director of the distribution scheme. See United States v. Fuller,
942 F.2d 454, 458 (8th Cir. 1991). Evidence showed that it was Dierling’s idea to kill
Danny Craig, that he put out a contract on his life, and that he induced others to beat
Craig. Witnesses testified that Holt, Perkins, and Craig were dealing drugs under
Dierling’s direction. Dierling also gave a firearm to Michelle Crawford while she was
transacting business on behalf of the conspiracy because he believed it was necessary
for her protection. Dierling recruited members of the conspiracy and supervised the
procurement of drug manufacturing materials. He offered to teach Candy True how to
produce methamphetamine. He also solicited the assistance of Danny Craig to pick up
drug manufacturing materials from his barn. Dierling brought others together to
manufacture the drug and set up a manufacturing laboratory on his property. See United
States v. Keene, 915 F.2d 1164, 1170 (8th Cir. 1990). He attempted to enlist Bobby
Collis in the manufacture of methamphetamine in order to raise money to get out of jail.
He called Candy True from jail and asked her to procure materials because he planned
to make the drug to raise money upon his release. See United States v. Wagner, 884
F.2d 1090, 1098 (8th Cir. 1989). There is no question that he was a leader or organizer.

       There was also sufficient evidence on which the court could find that Dierling
“willfully obstructed or impeded, or attempted to obstruct or impede, the administration
of justice” when he burned his house and barn and fled from police on two occasions.



                                         -23-
USSG § 3C1.1. Enhancement is appropriate where “misconduct occurs with knowledge
of an investigation, or at least with a correct belief that an investigation is probably
underway.” United States v. Oppedahl, 998 F.2d 584, 586 (8th Cir. 1993). There was
evidence that Dierling set fire to his property at a time he knew he was the target of an
investigation into the production and distribution of methamphetamine. He knew that
the police had searched his property only days before the fire. Dierling told government
witness Michelle Crawford around the time of the fire that they had to go to Iowa to get
methamphetamine because “things were hot around there” which she understood to
mean “the cops were on him.” Dierling also told Bobby Collis while the two were in jail
that he set fire to his property to destroy the remnants of a methamphetamine laboratory.
There was enough evidence to show that Dierling “consciously act[ed] with the purpose
of obstructing justice.” United States v. Watts, 940 F.2d 332, 332-33 (8th Cir. 1991)
(quoting United States v. Stroud, 893 F.2d 504, 507 (2d Cir. 1990).

       Dierling argues that the court improperly assessed a two level enhancement
because of his flight and shooting of deputy Clark. He says that Clark was attempting
to arrest him on warrants for the violation of a protective order and so his flight should
not be attributed to any awareness of an investigation of his drug activities. There was
evidence, however, that he knew he was suspected of drug dealing and that he intended
to evade capture and protect the illegal operation. This was sufficient to support the
district court’s obstruction ruling.

                                           D.

       In summary, the trial court made detailed findings at the sentencing hearing as to
the credibility of the witnesses, addressed thoroughly and individually the objections of
each appellant to the Presentence Report, and otherwise fully complied with the relevant
requirements of Fed R. Crim. P. 32. There was evidence to support the findings, and
there is no reason to overturn them or to require resentencing.



                                          -24-
                                           VIII.

       Appellants were involved in a large methamphetamine conspiracy, and the
conspirators acted ruthlessly at times to protect its operation. There was a wealth of
evidence to support the jury verdicts and the sentencing findings. Appellants have not
shown reversible error at their joint trial or that they are entitled to a new trial, and for
the reasons already discussed we affirm the judgments.

A true copy.

       Attest:

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




                                           -25-
