United States v. Hahn

                  UNITED STATES COURT OF APPEALS
                      FOR THE FIRST CIRCUIT

                                           

No. 93-1858

                    UNITED STATES OF AMERICA,

                            Appellee,

                                v.

                           ROBERT HAHN,

                      Defendant, Appellant.

                                           

           APPEAL FROM THE UNITED STATES DISTRICT COURT

                FOR THE DISTRICT OF NEW HAMPSHIRE

          [Hon. Paul J. Barbadoro, U.S. District Judge]
                                                      

                                           

                              Before

                      Selya, Cyr and Boudin,

                         Circuit Judges.
                                       

                                           

   Paul J. Haley, with whom Scott L.  Hood and Law Office of Paul J.
                                                                    
Haley were on brief for appellant.
   
   David A. Vicinanzo,  Assistant United States Attorney,  with whom
                     
Peter E. Papps, United States Attorney, was on brief for appellee.
            

                                           

                          March 9, 1994

                                           

          CYR, Circuit  Judge.  Appellant Robert  Hahn challenges
          CYR, Circuit  Judge.
                             

various  trial court rulings and  the sufficiency of the evidence

supporting  his convictions for  using or  carrying a  firearm in

relation to  a drug trafficking  crime, 18 U.S.C.    924(c), con-

spiring to possess and distribute marijuana, 21 U.S.C.   846, and

conducting  a continuing criminal enterprise, 21 U.S.C.   848(a),

(c).  Careful review discloses no error.

                                I

                            BACKGROUND
                                      

          We recite the  relevant facts in the  light most favor-

able to the verdict.   See United States v. Welch,      F.3d    ,
                                                 

   , No. 92-1368  (1st Cir. Dec. 30, 1993,  slip op. at 19).   In

1992, Hahn and ten other  defendants were jointly indicted in the

United  States District Court for  the District of New Hampshire,

as former members of a nationwide marijuana trafficking conspira-

cy spanning  more than a decade  and headed by one  Alberto "Dad"

Lujan.  As a principal  underboss, Hahn had been responsible for,

inter alia, transporting smuggled  Mexican marijuana from Arizona
          

for  distribution  in California,  Colorado, Michigan,  New Hamp-

shire, Massachusetts and New York, among other locales.

          In the early 1980s, Hahn and Lujan were local marijuana

dealers seeking to penetrate marijuana markets outside Arizona in

order  to capitalize  on  their  connections  with  suppliers  in

Mexico.   Eventually,  Hahn established  a business  relationship

                                2

with  Mark  Heino, a  New  Hampshire  native living  in  southern

California.   Some of  the marijuana Heino  bought from  Hahn, he

resold  in California.   The  rest Heino  distributed  during his

frequent trips to New Hampshire.   Heino himself became an under-

boss in the Lujan organization,  a position he retained until his

arrest on trafficking charges in early 1984.

          With  Heino  out  of  circulation,  the  New  Hampshire

operation was taken over by  Hugh Mulligan, another New Hampshire

native.  Like  Heino, Mulligan had been recruited  into the Lujan

organization by  Hahn, who  thereafter supervised  Mulligan's New

Hampshire operation.   Later,  when the  New Hampshire  marijuana

market  softened, Mulligan  introduced Hahn  to  Dennis and  P.J.

Dougherty,  Long Island residents  with New Hampshire  ties.  The

Doughertys afforded the  Lujan organization access to  the lucra-

tive  Metropolitan New York marijuana market, and large marijuana

shipments were soon being trucked in from Arizona.  Several years

later,  after the  Doughertys dropped  out of  the picture,  Hahn

established a high-volume  marijuana trade with another  New York

dealer.   Meantime, Heino was  released from prison  in mid-1986,

returned to New Hampshire, and reestablished himself in the Lujan

organization.    During  this period,  Hahn  concentrated  on the

organization's interests in Arizona,  Metropolitan New York,  and

New Hampshire.

                                3

          Hahn's primary  role was  to supervise marijuana  ship-

ments from Arizona  to New York and New England.1  In early 1991,

Lujan set  up a bogus  produce-trucking operation as a  cover for

the marijuana shipments.  A professional truck  driver, one Roger

Bradley, was recruited for the long-haul runs between Arizona and

the  Northeast.   Upon  arrival  at his  East  Coast destination,

Bradley  would contact Hahn to arrange for offloading.  Normally,

Bradley  would "deadhead"  back to  Arizona, but  on occasion  he

transported large quantities of currency back to Lujan at  Hahn's

request.2

          The cross-country trucking operation was a success.  At

its  apex, during 1991 alone, thirteen to fifteen tractor-trailer

loads were transported from Arizona to the Northeast under Hahn's

                    

     1Hahn's secondary role  was to  ensure the  security of  the
organization's  marijuana supply in  Arizona.   Several witnesses
testified  that Hahn  almost always  carried  a .45  caliber Colt
Commander handgun.  Coconspirator Michael Sheehan testified  that
Hahn admitted conducting  raids, or "rips," on  rival traffickers
and   stealing their marijuana, thereby impeding the competition.
Hahn told Sheehan that  he had been wounded  by gunfire during  a
"rip" in Tucson on December 8, 1989.   At trial, a police officer
testified to having found Hahn in the aftermath of the December 8
shootout, and the government introduced photographs depicting the
shootout scene, strewn with bullets and bales of marijuana. 

     2The cross-country transportation operation required manpow-
er.  The  principal truck driver was Bradley, but on at least one
occasion  coconspirators  Michael  Sheehan and  Jeff  Heino, Mark
Heino's brother, were   brought to Arizona  by Hahn to help  with
the driving.   Hahn also recruited his stepson,  Craig Nezat, and
Nezat's cousin,  Robert Mercado,  to come to  New York  to assist
with  offloading.   And,  finally,  Hahn often  used  either Jeff
Heino, Sheehan, or  Ken White, as a helper    to drive and assist
in offloading the marijuana.   Although Mulligan took a back seat
to  Mark Heino after the  latter was released  from prison, on at
least one occasion Hahn used Mulligan as a courier for transport-
ing the organization's currency from New York to Arizona.

                                4

supervision,  approximating 5,000  pounds apiece.    The criminal

conspiracy unravelled shortly thereafter,  however.  During 1992,

Hahn's performance faltered, due apparently to his cocaine habit,

and he was cashiered by Lujan.  Heino was unable to reestablish a

supply line between Arizona and New Hampshire.  Finally, Hahn was

arrested in Arizona on November 12, 1992.3

                                II

                            DISCUSSION
                                      

A.   Sufficiency of the Evidence
                                

     1.   Standard of Review
                            

          The challenges Hahn  asserts to the sufficiency  of the

evidence  and to  the  denial  of his  motions  for judgments  of

acquittal  "raise a  single issue."   United  States v.  Batista-
                                                                 

Polanco, 927 F.2d 14, 17 (1st Cir. 1991), quoted in United States
                                                                 

v.  Cassiere, 4 F.3d 1006, 1011  (1st Cir. 1993); see also Welch,
                                                                

    F.3d  at      [slip op. at  19].   The verdicts  are reviewed

under well-recognized standards:

          We assess the sufficiency  of the evidence as
          a whole, including all reasonable inferences,
          in the  light most favorable to  the verdict,
          with  a view to  whether a rational  trier of
          fact could  have found  the defendant  guilty
          beyond a reasonable  doubt.  We do  not weigh
          witness credibility,  but resolve  all credi-
          bility issues in  favor of the verdict.   The
          evidence may be  entirely circumstantial, and
          need not exclude  every reasonable hypothesis
          of  innocence; that  is,  the factfinder  may

                    

     3Hahn's  ten codefendants entered  into plea agreements with
the government.

                                5

          decide  among  reasonable  interpretations of
          the evidence.

Batista-Polanco, 927 F.2d at 17 (citations omitted).
               

     2.   Continuing Criminal Enterprise
                                        

          A conviction  under 21 U.S.C.    848 for engaging  in a

continuing criminal  enterprise ("CCE") requires  proof beyond  a

reasonable doubt that  the defendant (1) committed a  felony drug

offense, (2) as  part of a continuing series  of such violations,

(3) in concert with  five or more persons in relation  to whom he

acted as a supervisor, organizer,  or manager, (4) and from which

multiple  operations  he  realized  substantial income  or  other

resources.   See, e.g., United States v. Rouleau, 894 F.2d 13, 14
                                                

(1st  Cir. 1990).   Hahn claims  that the  government established

neither the third nor the fourth element of the CCE offense.

          Under the  familiar construction accorded the third CCE

element, the jury  need only have found that  the predicate crime

was committed in concert with at least five different individuals

in relation to whom the  defendant served as an organizer, super-

visor,  or in any  other management  position.   See 21  U.S.C.  
                                                    

843(c)(2)(A); see also United States v. David, 940 F.2d 722, 730-
                                             

32 (1st  Cir. 1991), cert.  denied sub nom., Toro  Aristizabal v.
                                                              

United States, 112 S. Ct. 605 (1991), and cert.  denied sub nom.,
                                                                

Yarden v.  United States, 112 S. Ct. 908 (1992), and cert. denied
                                                                 

sub  nom., Toro  Aristizabal v.  United States,  112 S.  Ct. 1298
                                              

(1992), and cert.  denied, 112 S. Ct. 2301  (1992); United States
                                                                 

                                6

v. Jenkins, 904 F.2d 549,  553 (10th Cir.), cert. denied,  115 S.
                                                        

Ct. 395 (1990).4

          The  record abounds with evidence that Hahn performed a

supervisory role in the Lujan organization which required manage-

ment of more  than five other individuals.   First, Hahn concedes

that  he  supervised Craig  Nezat and  Robert Mercado.   Further,

there  is  uncontroverted evidence  that  he exercised  virtually

exclusive managerial control of marijuana transportation  between

Arizona and  the Northeast, which means that  truck drivers Roger

Bradley, Michael Sheehan and Jeff Heino were under Hahn's control

and  supervision from time to time  as well.  Although these five

subordinates were enough  to establish the third CCE element, Ken

White and Hugh Mulligan were managed by Hahn as well.   See supra
                                                                 

at pp. 3-4.5

                    

     4As the Tenth Circuit explained in Jenkins: 
                                               

          [The  CCE statute's]  use  of the  indefinite
          article when describing 'a position of organ-
                                  'a
          izer' or 'a supervisory position or any other
                   'a                         any other
          position of  management' contemplates  that a
          given network  may have  many persons  in au-
          thority.  Thus, the defendant need not be the
          dominant organizer  or manager of  the enter-
          prise; he  need only  occupy some  managerial
                                       some
          position with respect  to five  or more  per-
          sons. 

Jenkins, 904 F.2d at 553 (emphasis in original).
       

     5It is therefore unnecessary to address Hahn's argument that
he did not control the New Hampshire branch  of the Lujan organi-
zation.  "[S]o  long as the  record supports a  finding that  any
                                                                 
five people  were under  [the defendant's]  control, our task  is
complete and the status of  the other individuals is immaterial."
David, 940 F.2d at 731 (emphasis in original).
     

                                7

          Hahn's  challenge to the sufficiency of the evidence on

the fourth CCE  element is unavailing as well.   The "substantial

income" requirement may  be met either by direct  evidence of the

revenues  realized and resources accumulated by the defendant, or

by  such circumstantial evidence  as the defendant's  position in

the criminal organization and the  volume of drugs handled by the

organization.  United States v. Roman, 870 F.2d 65, 75 (2d Cir.),
                                     

cert. denied, 490  U.S. 1109 (1989); United States  v. Sisca, 503
                                                            

F.2d 1337,  1346 (2d Cir.),  cert. denied, 419 U.S.  1008 (1974).
                                         

The "substantial income"  test establishes no fixed  minimum, but

is intended "to  exclude trivial amounts derived  from occasional

drug  sales," Roman,  870 F.2d at  75; see also  United States v.
                                                              

Medina, 940  F.2d  1247, 1251  (9th  Cir. 1991)  ("The  practical
      

meaning of 'substantial income  or resources' will normally be  a

question for the trier of fact").

          There is overwhelming circumstantial evidence that Hahn

derived "substantial  income" from  the management  services ren-

dered to the Lujan organization.   The government need only prove

revenue, not  profit.   See, e.g., Roman,  870 F.2d  at 75.   The
                                        

sheer  scope of  the  conspiracy,  which  generated  millions  of

dollars from many  tons of marijuana over several years, provided

ample  basis for a  reasonable inference  that Hahn  realized far

more than trivial  amounts of income from the  organization.  See
                                                                 

id.    For example,  the trial  testimony indicated  that Bradley
   

alone transported approximately  50,000 pounds of marijuana  from

Arizona to  the Northeast  and over $1  million in cash  from New

                                8

York  to  Arizona at  Hahn's  direction  on one  occasion  alone.

Coconspirator  Ken  White  testified that  he  purchased  tens of

thousands of dollars  worth of automobiles and handguns at Hahn's

request.  And coconspirator Jeff Heino testified  that Hahn typi-

cally spent $1,500 to $2,000 per day while Heino was working with

him  in the  field  on  organization business.    The fourth  CCE

element was established beyond a reasonable doubt.6

     3.   Conspiracy to Possess and Distribute Marijuana
                                                        

          Next,  appellant  challenges  the  sufficiency  of  the

evidence supporting his  conviction for conspiring  to distribute

marijuana, see  21  U.S.C. 846,  which  requires proof  beyond  a
              

reasonable doubt  that "(1) a  conspiracy existed, (2)  . . . the

defendant knew  of it, and (3) . . .  he voluntarily participated

in it."  David, 904  F.2d at 735.   "A  criminal conspiracy  is a
              

tacit or  explicit agreement to  perform an unlawful act  or omit

one the law  requires."  United States v. Penagaricano-Soler, 911
                                                            

F.2d 833, 840 (1st Cir.  1990), citing Iannelli v. United States,
                                                                

420 U.S.  770, 777 (1975).   The illicit agreement may  be estab-

lished by  direct and circumstantial evidence.   Batista-Polanco,
                                                                

927 F.2d at 19.

          Hahn's claim that the government failed to establish an

agreement  among  him and  his  confederates is  frivolous.   The

                    

     6Although Hahn's father testified that throughout the period
in question his son lived in a trailer behind the family home and
was "constantly  asking for money,"  we may not presume  the jury
incapable  of circumspection.   See Batista-Polanco, 927  F.2d at
                                                   
17.

                                9

evidence undergirding the CCE conviction  alone, see supra at pp.
                                                          

6-8, was sufficient to support a jury finding that Hahn conspired

with  at least  seven  other  persons  to  distribute  marijuana.

Beyond  that, however, Hahn  concedes that  he was  a "middleman"

between "Dad"  Lujan and Mark  Heino.  Finally, the  evidence was

not nearly so limited, but demonstrated beyond a reasonable doubt

that  Hahn  was a  key  conspirator  in  a large-scale  marijuana

conspiracy involving many other people.

     4.   Firearms Conviction
                             

          Hahn contends  that the  government  did not  establish

that he  "used or carried" a firearm during  and in relation to a

drug  trafficking crime as required by 21  U.S.C.   924(c).  This

claim too is  without merit.  Hahn concedes  that "many witnesses

testified  at trial  regarding the  fact that  the defendant  oc-

casionally carried  a weapon."7   Since we will  not second-guess

credibility determinations by the jury, id. at 17, that testimony
                                           

was sufficient  evidence in  itself  since these  weapon-carrying

incidents  involved  activities  in  direct  furtherance  of  the

conspiracy.  See supra notes 1 & 7.
                      

                    

     7We mention  but a few examples.  First, coconspirator Craig
Nezat testified that  Hahn carried a gun  during their marijuana-
related business trips  to New York.   Second, coconspirator  Ken
White testified that he bought more than one dozen guns for Hahn,
and that Hahn  almost always carried  a gun.  Finally,  when Hahn
was  found at the December  8, 1989 shoot-out  scene, he lay only
inches from  a .45  Colt Commander, his  signature handgun.   See
                                                                 
supra at note 1.
     

                                10

B.   Motions for Mistrial
                         

          Hahn charges  error in the  denial of  his motions  for

mistrial based on  the government's failure to establish that his

involvement in the "rip" shootout in Tucson was in furtherance of

the conspiracy.   A mistrial need not  be allowed absent a  clear

showing of prejudice.  United States v. Sclamo, 578 F.2d 888, 891
                                              

(1st Cir. 1978); United  States v. Pappas, 611 F.2d 399, 406 (1st
                                         

Cir. 1979).  We review the mistrial ruling  for "abuse of discre-

tion."   United States v.  Dockray, 943 F.2d  152, 157 (1st  Cir.
                                  

1991).

          After the  government's opening statement,  the defense

moved for a  mistrial based on the prosecutor's  reference to the

Tucson "rip."   See supra note 1.  The  government represented at
                         

sidebar  that it  would link  the  Tucson "rip"  with the  larger

conspiracy through the testimony  of coconspirator Michael  Shee-

han.   The  court accordingly  denied  the motion  for  mistrial,

without prejudice to  its renewal.  Sheehan  later testified that

Hahn had  admitted that he  conducted the Tucson "rip"  to "knock

out  the  competition."   Further,  Sheehan  testified  that Hahn

conducted  at least  one other  such  raid while  Sheehan was  in

Arizona.

          At the close of the government's case,  the court ruled

the Tucson "rip" evidence admissible  as an overt act in further-

ance  of  the conspiracy.   Hahn  presents no  argumentation even

remotely suggestive of an abuse of discretion, merely reiterating

the unsupported  conclusion that the  Tucson "rip" was part  of a

                                11

separate  conspiracy.  The government correctly responds that the

jury  reasonably could have found otherwise;  that is, by intimi-

dating  the  competition,  and  stealing  their  marijuana,  Hahn

furthered the interests of the Lujan organization.

                                12

C.   Evidentiary Rulings
                        

          Hahn filed a pretrial motion in limine to  preclude, as
                                                

irrelevant or unduly  prejudicial:  (1)  testimony of an  Arizona

state  trooper who  had made  a routine  stop of a  vehicle being

driven by Hahn; and (2) testimony of another officer who searched

a  different vehicle  (subsequently linked  with  Hahn), and  the

physical evidence recovered in the ensuing inventory search.  

     1.   Arizona Traffic Stop
                              

          Arizona State  Trooper Carlos Contreras  testified that

he encountered Hahn in  February of 1992 when he stopped  a black

Ford  pickup truck with  New Hampshire license  plates because it

lacked mud flaps.   The driver, Hahn, was in lawful possession of

a .45  caliber Colt  Commander.  The  government argued  that the

traffic-stop evidence  was highly probative  of the scope  of the

alleged conspiracy and Hahn's role in it, and that it corroborat-

ed important testimony provided by other prosecution witnesses.8

          Hahn  argues that the traffic-stop and handgun evidence

should not have survived  the gauntlet for "other acts"  evidence

established under Federal Rules of Evidence 403 and 404(b). 

          First, the past incident must have some rele-
          vance  other  than  to  show the  defendant's
          propensity to commit the crime. United States
                                                       

                    

     8First, it established that Hahn was driving a New Hampshire
vehicle in Arizona.   Second, the black  Ford pickup registration
was in Hahn's name, and indicated a dwelling owned by coconspira-
tor Mark Heino as Hahn's New Hampshire address.  Third, Ken White
had testified  to buying a  black Ford pickup at  Hahn's request.
Fourth, the  Colt  Commander  .45 bore  the  same  serial  number
appearing on the  bill of sale for  a handgun Ken White  had pur-
chased at Hahn's request.

                                13

          v. Ferrer-Cruz, 899 F.2d  135, 137 (1st  Cir.
                        
          1990).  Second, even  if specially  relevant,
          the danger of  prejudice cannot substantially
          outweigh the probative value of the evidence.
          Id. at 138; Fed. R. Evid. 403.
             

United States v.  Agudelo, 988 F.2d 285, 287 (1st Cir. 1993); See
                                                                 

United  States v.  Williams, 985  F.2d 634,  637 (1st  Cir. 1993)
                           

(similar).

          The  district court first  conducted an in  camera con-
                                                            

ference with  counsel to  delimit Trooper Contreras's  testimony,

heard  the  testimony, then  found  that the  testimony  forged a

relevant  link among  various  regional  elements  in  the  Lujan

organization.   Then, with  defense counsel's imprimatur,  a firm

jury instruction was given to the effect, inter alia, that it was
                                                    

lawful for Hahn to possess the handgun.9

          The  court correctly  ruled that the  challenged "other

acts" evidence  was not  precluded under  Rule 404(b)'s  absolute

bar,  which "excludes  evidence . . .  relevant  only because  it
                                                     

shows bad character," United States v. Ferrer-Cruz, 899 F.2d 135,
                                                  

137  (1st Cir.  1990) (emphasis in  original); see  Williams, 985
                                                            

                    

     9Immediately after  Trooper Contreras's  direct examination,
the district court instructed the jury as follows:

          Ladies  and Gentleman  of the jury,  you have
          heard testimony  from this witness  about Mr.
          Hahn's  possession of  a firearm  in Arizona.
          The witness has already testified that it was
          entirely lawful for Mr.  Hahn to possess that
          firearm and  the witness's statement  is cor-
          rect and you are to understand  from me as my
          instruction on the  law that it  was entirely
          lawful for Mr.  Hahn to possess that  firearm
          and you're  not to draw any inference against
          Mr. Hahn because he was in possession of that
          firearm as testified to by this witness.

                                14

F.2d at 637; all evidence  derived from the traffic stop, includ-

ing  the handgun,  clearly bore  direct  relevance to  legitimate

issues, see note 7 supra.   Furthermore, possession of a licensed
                        

firearm is neither a bad act nor indicative of bad character.

          Under the  required Rule  403 balancing,  see id.,  the
                                                           

"other acts" evidence itself posed scant  risk of engendering any
                            

improper  inference of predisposition to possess or use a firearm

unlawfully, as distinguished  from lawful access to  a particular
                                         

firearm, a  piece of evidence highly relevant  to Hahn's involve-

ment  and role  in  the  alleged conspiracy  and  CCE.   Whatever

"prejudice" resulted  by reason of  the fact that Hahn  was being

tried, inter alia, on a weapons charge, was not only mitigated by
                 

the  limiting instruction, see  Huddleston v. United  States, 485
                                                            

U.S. 681, 691-92, citing United States v. Ingraham, 832 F.2d 229,
                                                  

235 (1st Cir.  1987), cert. denied, 486 U.S. 1009 (1988), but did
                                  

not  derive unfairly  from the  challenged  evidence itself.   We

discern no unfair prejudice and no abuse of discretion.

     2.   The Lincoln Mark VII
                              

          Hahn  attempted  to  preclude evidence  seized  from  a

Lincoln Mark  VII abandoned near  an airport in Islip,  New York.

An inventory search yielded, inter  alia, a .45 caliber Derringer
                                        

handgun, several Colt  .45 caliber ammunition clips,  and various

travel documents  in Hahn's  name.   Coconspirator Ken  White had

testified  to purchasing an identical Lincoln  Mark VII at Hahn's

behest, and several witnesses testified that the Lincoln was used

by  Hahn in his  New York City  area activities in  behalf of the

                                15

Lujan organization.  The Derringer  bore a serial number matching

that on the  bill of sale White received when he purchased it, as

he did  other handguns,  at Hahn's request.   Finally,  among the

travel  documents found  in the  Lincoln  was the  receipt for  a

round-trip  airline ticket  issued  in  Hahn's  name  for  travel

between Tucson and Islip. 

          Hahn argues that this evidence should have been exclud-

ed under Rule  403 because its prejudicial  effect outweighed its

probative value.   The  difficulty with Hahn's  claim is  that he

"has  not shown  that  the  probative value  of  the 'other  act'

evidence was substantially  outweighed by its unfair  prejudice."
                                                    

United  States v.  Carty, 993  F.2d  1005, 1011  (1st Cir.  1993)
                        

(emphasis in  original); see United  States v. Rodriguez-Estrada,
                                                                

877 F.2d 153, 156 (1st Cir.  1989) ("all evidence is meant to  be

prejudicial; it is only unfair prejudice which must be avoided").

Although  evidence of  handgun possession  may  indeed invite  an

inference that the  defendant used the gun,  the entirely legiti-
                                  

mate predicate inference for so concluding is that prior  posses-
              

sion makes it  "more probable" that the defendant  used a handgun
                                                       

than would be the case if there were no such evidence.   See Fed.
                                                            

R.  Evid.  401.   Thus,  no unfair  inference  of character-based

predisposition was necessary to constitute the seized handgun and

ammunition  probative  evidence  on  several  important   factual

issues, including Hahn's activities in the  New York area.  As no

cautionary  instruction was  requested, we  discern  no abuse  of

discretion.

                                16

                                17

D.   Impeachment Evidence
                         

          After trial,  Hahn's attorney  became aware  of a  plea

agreement  and a  police report  relating  to government  witness

Roger  Bradley  which  had  not  been  provided to  the  defense.

Claiming that these documents would have been useful for impeach-

ment purposes, Hahn moved  for a new  trial.  The district  court

denied the motion.

          "[T]he district court's determination on the materiali-

ty of  newly discovered  evidence in  prosecutorial nondisclosure

cases  is ordinarily  accorded  deference."    United  States  v.
                                                             

Sanchez,  917 F.2d 607, 618 (1st  Cir. 1990) (citations omitted),
       

cert. denied, 499 U.S. 977 (1991).  A new trial  is in order only
            

if Hahn can demonstrate a reasonable probability  that the result

would  have been  different had  the defense provided  the undis-

closed evidence before trial.   See Barrett v. United States, 965
                                                            

F.2d 1184, 1189 (1st Cir. 1992); Sanchez, 917 F.2d at 617.
                                        

          The district court ruled that  no such showing had been

made by Hahn because:  (1) defense counsel had been provided with

a plea agreement  between Bradley and the  United States Attorney

for the District of New Hampshire, and had been made aware of the

existence of the  Arizona plea agreement even though the document

itself  was not  provided; (2)  Hahn's counsel  made good  use of

these plea agreements at  trial and, indeed, Bradley admitted  on

cross-examination that he  was hoping for  a lighter sentence  in

exchange for his testimony; and (3) the Arizona police report was

cumulative,  as it contained  information previously  provided to

                                18

the defense in other documents,  and had been effectively used in

cross-examination.   Careful review  leaves no  doubt that  these

findings were well founded, in  law and fact.  "'Impeachment evi-

dence, even that which tends to further undermine the credibility

of the  key government witness whose credibility has already been

shaken  due to  extensive cross-examination,  does  not create  a

reasonable  doubt that did not otherwise exist when that evidence

is cumulative  or collateral.'"   Id.  at 618-19  (quoting United
                                                                 

States v.  Shelton, 588  F.2d 1242, 1248  (9th Cir.  1978), cert.
                                                                 

denied, 442 U.S. 909 (1979)).
      

E.   Sentencing
               

          The district  court imposed  two concurrent  life terms

for  the CCE  and  conspiracy  count convictions,  as  well as  a

mandatory, consecutive five-year  term for  the firearms  offense

under  18 U.S.C.   924(c); a $25,000  fine; costs of confinement;

and  five years'  supervised release.10   In  accordance  with 18

                    

     10These sentences were imposed  pursuant to the  November 1,
1992, version of the Sentencing Guidelines.  See U.S.S.G.   1B1.1
                                                
(1992).  The    924(c) conviction triggered a  mandatory consecu-
tive five-year sentence.  See id.   2K2.4.  The CCE and conspira-
                                 
cy counts  were grouped  pursuant to  U.S.S.G.   2D1.5,  comment.
(n.4).  See id.   3D1.3.
               
     On  the  conspiracy  conviction,  the  court  conservatively
calculated  the drug quantity  at 10,000  to 30,000  kilograms of
marijuana,  see id.    2D1.1(c)(4),  for  a  base  offense  level
                   
("BOL") of  36, augmented by a two-level enhancement for possess-
ing a firearm, see id.    2K2.4, comment. (n.2), and a four-level
                      
enhancement for Hahn's  leadership role, see id.    3B1.1(a), for
                                                
an adjusted base offense level ("ABOL") of 42.
     On the CCE count, the ABOL was 42 as well, see  id.   2D1.5,
                                                        
and  Hahn's  category I  criminal  history status  resulted  in a
guideline sentencing  range of 360  months to life. See  id.   5A
                                                            
(sentencing table).

                                19

U.S.C.    3553(c)(1), the  district court  entered  the following

statement of  reasons for sentencing  Hahn at the upper  limit of

the guideline sentencing range ("GSR"):

          1.   Hahn  was  a  career  criminal  who  had
               "devoted his entire life to the business
               of trafficking in illegal drugs."

          2.   Hahn used weapons, violence, and intimi-
               dation as a day-to-day part of his busi-
               ness operation.

          3.   Estimated  conservatively, the  quantity
               of  marijuana attributable  to Hahn  was
               well in excess  of the 10,000  kilograms
               necessary  to  qualify for  the  offense
               level found  applicable in  the pre-sen-
               tence report.

          4.   Hahn managed and  corrupted considerably
               more than five people over the course of
               the conspiracy.

The only challenge to these findings is directed at the amount of

marijuana for which Hahn was held responsible.

          The  "drug quantity" determination  must be based  on a

preponderance of the  evidence, U.S.S.G.    1B1.3, and we  review

only  for clear  error.  United  States v. Tracy,  989 F.2d 1279,
                                                

1287  (1st Cir.),  cert.  denied,  113 S.Ct.  2393  (1993).   The
                                

presentence report  recommended that  64,200 pounds  of marijuana

(approximately  29,000 kilograms) be attributed to Hahn, based in

part on  the trial testimony  of several witnesses  who recounted

particular  transactions during the  decade-long period from 1980

to early 1991, augmented by an estimate of the amount transported

by  Roger Bradley in  thirteen tractor-trailer loads  during 1991

alone.  The  court conservatively estimated  the total amount  at

49,700 pounds for sentencing purposes.

                                20

          Hahn's challenge  is based exclusively on a credibility

attack against Bradley's trial testimony.  But see  United States
                                                                 

v. Sepulveda,     F.3d    ,      (1st Cir. 1993) [Slip  op. at 72
            

(December 20, 1993)]  (where testimony  provides competent  basis

for estimating drug quantity,  we need go no further, id.  at    
                                                         

[slip op.  at 77]).   Not only  are the  district court  findings

fully supported, but Hahn does not allege that he was responsible

for  less than  the  10,000 kilograms  of  marijuana required  to

trigger BOL 36.  See note 10 supra.  Thus, any alleged discrepan-
                                  

cy in weight would be immaterial for guideline sentencing purpos-

es.  

          Affirmed.
                  

                                21