200 F.3d 529 (7th Cir. 2000)
United States of America, Plaintiff-Appellee,v.James E. Johnson, Defendant-Appellant.
No. 99-1414
In the United States Court of Appeals  For the Seventh Circuit
Argued September 10, 1999Decided January 13, 2000

Appeal from the United States District Court   for the Eastern District of Wisconsin.  No. 97 CR 211--Charles N. Clevert, Judge. [Copyrighted Material Omitted]
Before Flaum, Manion, and Diane P. Wood, Circuit Judges.
Manion, Circuit Judge.


1
James Johnson was convicted by a jury of one count of conspiracy to distribute and to possess with intent to distribute in excess of five kilograms of cocaine. He was sentenced to 360 months of imprisonment. He argues on appeal that the government failed to provide Jencks Act material and that the district court erred in admitting hearsay at his trial. As to his sentence, Johnson argues that the district court erred in adopting the government's determination of the amount of cocaine attributable to him. Finding no error, we affirm.

I.

2
The prosecution's primary witness at Johnson's trial was Michael Blake, one of Johnson's associates and drug suppliers who had agreed to cooperate with the authorities. Blake testified that he began distributing cocaine in the Milwaukee, Wisconsin area around 1979. He met Johnson around that time through Johnson's brother, Charles, and began distributing drugs to James Johnson. Blake's drug distribution was periodically interrupted by short stints in prison, but when he was released in 1995, a former prison buddy--Candelario Nevarez-Diaz-- contacted him and proposed a cocaine dealing venture. Nevarez-Diaz agreed to front the cocaine, meaning Blake would pay for it only after he had sold it to others. That very night, Nevarez-Diaz fronted Blake 125 grams of cocaine, which Blake in turn fronted to Johnson and another individual, Gordon Hagenkord. Blake and Hagenkord also fronted cocaine to Robert Schultz1 and his stepdaughter Colleen Hanson,  who sold it out of Shultz's Milwaukee bar, the  Blue Ribbon Pub.


3
The sales continued and increased to a point where in early 1996, Nevarez-Diaz was supplying Blake with one kilogram of cocaine every two months. Blake, in turn, delivered some of the cocaine to Johnson's home in Milwaukee. Blake testified that in 1996, he delivered up to two kilograms of cocaine to Johnson at any one time,  and Johnson paid him $28,000 for each kilogram.  By this time, Blake was working closely with Nevarez-Diaz and even used Nevarez-Diaz's money  to purchase a Chevrolet Lumina to transport drugs  from Arizona. In 1997, Nevarez-Diaz supplied Blake with around 5 to 10 kilograms of cocaine every ten to twelve days, for which Blake paid  him $22,000 per kilogram. Blake, in turn, supplied Johnson with between 3 and 4 kilograms of cocaine every ten to twelve days, and sold it on credit for about $27,000 per kilogram. Blake estimated that between January 1, 1996 and July 24, 1997 he supplied Johnson with between 35 and  45 kilograms of cocaine.


4
On July 24, 1997, the police finally caught up with Blake when they pulled his car over for a traffic violation. A search of his vehicle turned up cocaine and around $120,000, some of which  Johnson had given to Blake for cocaine. Charged  with possession of cocaine and facing a long  stretch in prison, Blake decided to cooperate  with the government. With the assistance of the police, he placed recorded telephone calls to Nevarez-Diaz, Johnson, and Hagenkord. Audio tapes  of Blake's four conversations with Johnson were  admitted into evidence and played for the jury.  The recorded conversations were consistent with Blake's testimony that he fronted cocaine to  Johnson and that Johnson was a willing  participant in the conspiracy.


5
Johnson testified at his trial, and although he admitted that he used cocaine, he denied that he  ever was involved in a drug conspiracy. Rather, Johnson stated that he and Blake sold seafood  products. According to Johnson, Blake would drop  off shrimp, which Johnson would peddle on the  street and for which he would pay Blake some of  the proceeds. Apparently the jury did not believe  him, as it convicted him of one count of  conspiracy with intent to distribute and  possession with the intent to distribute cocaine,  in violation of 21 U.S.C. sec. 841(a)(1). With an offense level of 37 and a criminal history  category of VI, Johnson was sentenced to 360  months of imprisonment, the shortest sentence  permitted under the Guidelines.

II.

6
A.  Co-Conspirator Exception to the Hearsay Rule


7
During direct examination, government witness Gordon Hagenkord was asked about his duties in carrying on the drug business after supplier Michael Blake was arrested. As part of his response Hagenkord stated that when he started selling drugs for Blake, "I took over the south side and J.J. [Johnson] had the north side."  Johnson first contends that the district court erred in admitting this testimony. Johnson argues that this statement, "J.J. had the north side", was inadmissible hearsay not covered by the co-conspirator exception because Blake's statement was not made in furtherance of the conspiracy.2


8
We review for an abuse of discretion the district court's decision to admit testimony while its factual findings are examined for clear error. United States v. Mojica, 185 F.3d 780, 788  (7th Cir. 1999); United States v. Petty, 132 F.3d 373, 379 (7th Cir. 1997). A statement is not considered to be hearsay if it is made by "a co-conspirator of a party during the course and in furtherance of the conspiracy." Fed. R. Evid.  801(d)(2)(E). To utilize the co-conspirator exception the government must show that: (1) a conspiracy existed; (2) the declarant and the defendant were both members of the conspiracy;  and (3) the statements were made in the course  and in furtherance of the conspiracy. Mojica, 185  F.3d at 788.


9
Statements which further the conspiracy must be  distinguished from mere idle chatter, narrative  declarations, and superfluous casual remarks  which do not further the conspiracy. United States v. Curry, 187 F.3d 762, 766 (7th Cir.  1999); United States v. Santos, 20 F.3d 280, 286  (7th Cir. 1994) (narrative discussions of past events were not statements made in furtherance of  the conspiracy). Statements made in furtherance of a conspiracy can take a variety of forms. Some examples include comments designed to assist in  recruiting potential members, to inform other  members about the progress of the conspiracy, to  control damage to or detection of the conspiracy,  to hide the criminal objectives of the  conspiracy, or to instill confidence and prevent  the desertion of other members. United States v.  Godinez, 110 F.3d 448, 454 (7th Cir. 1997); United States v. Stephenson, 53 F.3d 836, 845  (7th Cir. 1995); United States v. Brookins, 52  F.3d 615, 623 (7th Cir. 1995); United States v.  Cox, 923 F.2d 519, 527 (7th Cir. 1991). Courts  assess a statement's ability to advance the  conspiracy in the context in which the statement  was made. United States v. Powers, 75 F.3d 335,  340 (7th Cir. 1996). "The statement need not have  been made exclusively, or even primarily, to  further the conspiracy." Id. Rather, the record  need only contain some reasonable basis for  concluding that the statement in question  furthered the conspiracy in some respect.  Stephenson, 53 F.3d at 845; United States v. Marin, 7 F.3d 679, 690 (7th Cir. 1993).


10
Here, Blake's statement, "J.J. had the north side", as repeated by Hagenkord, served several purposes. First the statement gave Hagenkord confidence in the confederacy through knowledge that others like Johnson were similarly willing  to participate in the conspiracy. More importantly, the statement conveyed to Hagenkord  the breadth of the conspiracy, its geographical  divisions, and his role with respect to those  divisions. Blake's statement could have furthered  the conspiracy by letting Hagenkord know that he  was to concentrate on the south side of town  while leaving the north side for Johnson. By precluding internecine competition, the conspiracy could more efficiently allocate its  resources and thereby minimize waste. Thus, we have held that the "in furtherance" element is satisfied when the statement conveys information  which helps conspirators perform their designated  roles, as Blake's comment did in this case.  Godinez, 110 F.3d at 454. Similarly, by  preventing the conspiracy from becoming a house  divided against itself, Blake's comment helped to  prolong the conspiracy. Because Blake's statement  to Hagenkord furthered the goals of the  conspiracy in several respects, the district  court did not err in admitting this testimony  under Rule 801(d)(2)(E).

B.  Jencks Act

11
Johnson also argues that the government failed to provide Jencks Act material, despite the  government's assurances to the district judge  that it had no such material with respect to  Gordon Hagenkord. In support of this argument,  Johnson directs our attention to his trial  attorney's cross-examination of Hagenkord.

Defense Counsel:

12
You said that persons [a prosecuting attorney, an  IRS agent, and DEA agent Rodel Babasa] read  reports to you?

Hagenkord:

13
They weren't reports. They were, they read back my own statements tome as I, they were putting  them down.

Defense Counsel:

14
That is, they had a document that had your statement in it?

Hagenkord:

15
Yes.

Defense Counsel:

16
And they read your statements back to you?

Hagenkord:

17
Yes.

Defense Counsel:

18
And they read your statements back and asked you  if that's what happened. Do I have that right?

Hagenkord:

19
Yes.


20
[Tr. Trans. Vol X pp. 348-49] According to  Johnson, this colloquy demonstrates that Jencks  material existed, and he argues that he never  received this material.


21
The Jencks Act was enacted in response to the  Supreme Court's holding in Jencks v. United  States, 353 U.S. 657 (1957). To ensure the  meaningful confrontation of government witnesses,  the Act requires the government, upon the  defendant's motion, to produce statements made by  any of its witnesses which the particular  witnesses signed, adopted, or approved, and which  pertain to their testimony at trial. 18 U.S.C.  sec. 3500(b); see also Fed. R. Crim. P. 26.2;  United States v. Lopez, 6 F.3d 1281, 1288 (7th  Cir. 1993). The hope is that these statements  will afford the defense a basis for effective  cross-examination of government witnesses and the  possible impeachment of their testimony without  overly burdening the government with a duty to  disclose all of its investigative material. See  United States v. O'Malley, 796 F.2d 891, 900 (7th  Cir. 1986); United States v. Snow, 537 F.2d 1166,  1168 (4th Cir. 1976). To ensure the government's  compliance with the Act the statute prescribes  penalties for failing to produce Jencks material,  which include the striking of the particular  witness's testimony or the declaration of a  mistrial. 18 U.S.C. sec. 3500(d).


22
In addressing Johnson's argument that the Jencks  Act was violated, the government presents a host  of rather weak arguments. First, the government  argues that Johnson only requested the  prosecutor's notes, and made no general call for  Jencks material. The trial transcript, however,  indicates that the prosecutor's notes were merely  one type of material sought by Johnson.  Furthermore, even if Johnson's request could be  construed as being limited to the prosecutor's  notes, where (as in this case) the defendant  sought at least some Jencks material and the AUSA  affirmatively represented to the defendant and  the district judge that no additional Jencks  material existed, the defendant is entitled to  rely on this representation. See United States v.  Knapp, 25 F.3d 451, 460 (7th Cir. 1994) (a  defendant need not move for each witness's Jencks  material where the government promises to produce  it).


23
The government then contends that Johnson's  request for the material was not sufficiently  specific. This argument fails because Johnson  requested all Jencks material, and he could  hardly identify documents by name when they are  not in his possession. For this reason, we have  said that a "defendant need not be extremely  particular in requesting such information. A  defendant's counsel cannot be overly specific  about items he may never have seen." United  States v. Allen, 798 F.2d 985, 997 (7th Cir.  1986).


24
The government then argues that Hagenkord did  not approve or adopt any statements, thereby  taking them outside the scope of the Act. The key  question here is "'whether the statement can  fairly be deemed to reflect fully and without  distortion the witness's own words.'" United  States v. Blas, 947 F.2d 1320, 1326 (7th Cir.  1991) (quoting Allen, 798 F.2d at 994).  Hagenkord's testimony indicates that the  government read his statements back to him and  that he then assented to them. Under longstanding  precedent this constitutes the witness's approval  of them. Allen, 798 F.2d at 994 (adoption or  approval can be shown by demonstrating that the  interviewer read back to the witness what he  wrote and the witness affirmatively stated his  approval); see United States v. Marrero-Ortiz,  160 F.3d 768, 776 (1st Cir. 1998); United States  v. Roseboro, 87 F.3d 642, 645 (4th Cir. 1996);  United States v. Ogbuehi, 18 F.3d 807, 810-11  (9th Cir. 1994); United States v. Newman, 849  F.2d 156, 160 (5th Cir. 1988). So since this is  precisely the process Hagenkord described, the  government's argument gets nowhere.


25
Next, the government seems to argue that the  purported statements at issue here were not  covered by the Jencks Act because the AUSA in  charge of the case was not the prosecuting  attorney who read the statements back to  Hagenkord and that he had no such document in his  immediate possession. But as our colleagues on  the Fifth Circuit have made clear, "[t]he Jencks  Act is not restricted to statements 'in the hands  of, or known to, the particular prosecuting  attorney assigned to the case, the U.S.  Attorney's office, the Criminal Section of the  Justice Department, or even the entire Justice  Department. Its order is unqualified.'" United  States v. Ramirez, 174 F.3d 584, 588 (5th Cir.  1999); United States v. Bryant, 439 F.2d 642, 650  (D.C. Cir. 1971) (the duty to disclose under the  Jencks Act "affects not only the prosecutor, but  the Government as a whole, including its  investigative agencies."). Thus, the document in  question was required to be turned over to  Johnson so long as any federal prosecuting  attorney or agent had possession of it.


26
Finally, the government contends that Johnson  has failed to show prejudice. On the surface,  this argument has some legitimacy because  although the text of the Act does not itself  require a demonstration of prejudice, courts have  held that relief may not be granted under the  Jencks Act without such a showing. United States  v. Riley, 189 F.3d 802, 806 (9th Cir. 1999)  ("While a defendant need not prove prejudice to  show a violation of the Jencks Act . . . when  there is no prejudice, a witness's testimony need  not be stricken."); United States v. Rosario-  Peralta, 175 F.3d 48, 53 (1st Cir. 1999)  (statements must be produced under the Jencks Act  whether they are exculpatory or not, but no  relief will be granted unless the failure to  disclose caused prejudice). Furthermore, a  showing of prejudice is part of the harmless  error analysis, which also applies to Jencks  violations. United States v. Wables, 731 F.2d  440, 448 (7th Cir. 1984) (a failure to produce  Jencks material may be a harmless error "only  when it is 'perfectly clear' that the  nondisclosure of Jencks Act statements did not  prejudice the defendant").3 But in making this  argument here, where the government allegedly did  not produce the purported Jencks documents for  the defendant to review, the argument's  limitations become readily apparent. A defendant  who does not know what is contained in unproduced  Jencks documents would be hard pressed to show  how that material would have benefitted his  defense. So assuming that Johnson was never given  the document in question, we can hardly hold  Johnson responsible for his failure to allege  prejudice. Indeed, it would be improper for  counsel who are ignorant of a document's contents  to argue that the failure to produce such a  document prejudiced the defense.


27
Ultimately, however, Johnson cannot prevail on  this argument because he neither raised it nor  attempted to develop it before the district  court. Although there is no question that he  initially requested Jencks documents, Johnson  never pursued this request after he learned at  trial about the alleged statements read back to  Hagenkord. Johnson should have informed the  district court about the potential contradiction  created by Hagenkord's testimony and the AUSA's  assertion that no Jencks material existed.  Similarly, as Agent Babasa was identified by  Hagenkord as being present while Hagenkord  approved the statements, Johnson's attorney  should have cross-examined Babasa about the  document and the meeting. Had Johnson done this,  and his efforts demonstrated the existence of a  probable Jencks document that had not been  produced, the district judge would have been  obliged to conduct a hearing on the matter,  thereby preserving the issue for appellate  review. Lopez, 6 F.3d at 1288-89. Alternatively,  if the district judge denied the defendant's  motion to hold such a hearing, that decision  itself would be subject to appellate scrutiny.  Id. at 1289. But because Johnson failed to take  any of these steps, he has waived this argument,  and we review only for plain error. United States  v. Shorty, 159 F.3d 312, 313 (7th Cir. 1998).


28
In an effort to get to the bottom of this, at  oral argument we asked AUSA Paul Kanter (who was  also the trial prosecutor) whether he knew to  which document Hagenkord was referring, and  whether the document was produced for Johnson.  Kanter unequivocally insisted that any such  document would have been turned over to Johnson  under the open file discovery policy of the  United States Attorney's office and that he had  no knowledge of any such government document that  was not given to Johnson. In light of these  assertions, if the document in question existed,  it was available to Johnson. This would certainly  explain why Johnson's trial counsel declined to  further explore this issue with Hagenkord and  Babasa on cross-examination, and why he didn't  present this argument to the district court or  seek a hearing on the matter. In short, Johnson  points to nothing in the record which indicates  that he did not receive this document, but  instead asks us to speculate that this may be the  case. Because the open file policy gives defense  counsel access to all information available to  the prosecution and there is nothing in the  record which definitively indicates that a Jencks  document was not produced for the defense, we  cannot say that there was an error here, much  less a manifest error that affected Johnson's  rights. See United States v. Cusimano, 148 F.3d  824, 828 (7th Cir. 1998).4 Accordingly, Johnson  cannot prevail on this argument.


29
C.  Calculation of Drug Amounts for  Sentencing


30
Finally, Johnson attacks the district court's  decision that, for purposes of determining his  relevant conduct for sentencing, Johnson should  be held responsible for between 15 and 50  kilograms of cocaine. This resulted in a base  offense level of 34. See U.S.S.G. sec.  2D1.1(c)(3). Johnson complains that the district  court adopted the Probation Department's  calculation of the drug quantity, which Johnson  asserts was just a wholesale adoption of the  government's position on the matter.5 Thus, he  seems to question the integrity of the  calculations.


31
We review the district court's calculations of  drug quantities for clear error. United States v.  Span, 170 F.3d 798, 803 (7th Cir. 1999). We must  affirm unless we are left with the firm  conviction that a mistake has been committed. Id.  The defendant has the right to be sentenced on  the basis of a reasonable quantity of reliable  information. United States v. James, 113 F.3d  721, 730 (7th Cir. 1997). The government has the  burden of establishing the type and amount of  drugs attributable to the defendant by a  preponderance of the evidence. Id. Thus, clear  error can occur with respect to drug calculations  when the government fails to marshal evidence of  a sufficient magnitude or where the calculations  are based on unreliable evidence. Span, 170 F.3d  at 803. In calculating the drug quantities, a  district court may "consider a wide range of  information so long as it has a "'sufficient  indicia of reliability to support its probable accuracy.'"  United States v. Robinson, 164 F.3d 1068, 1070  (7th Cir. 1999) (quoting United States v. Taylor,  72 F.3d 533, 543 (7th Cir. 1995)). In assessing  the reliability of the evidence we will leave  credibility determinations to the sound  discretion of the district court. United States  v. Miner, 127 F.3d 610, 615 (7th Cir. 1997).


32
Here, the district judge stated his reasons for  calculating the drug quantity as he did, and the  evidence he relied upon in making the  calculation.


33
Well, I have listened carefully to your  arguments and have had a chance to look at some  of the transcript which is available. Among the  things that I note from my review of the record  set forth in the transcript and my notes as well  as my recollection of the witnesses as they  testified is that there were some places where  there were inconsistencies in the testimony of  Mr. Blake and Mr. Hagenkord and Mr. Babasa.


34
But notwithstanding that Blake and Hagenkord in  my view were truthful, truthful in the relevant  aspects insofar as drug quantities are concerned.  I note that their testimony was corroborated in  large measure by the tape, the conversations of  Mr. Johnson. This conspiracy lasted at least 21  months. And as Mr. Kanter has pointed out, if at  least one kilogram was delivered each month then  Mr. Johnson was responsible for at least 21 kilos  and the quantity of drugs for which he can be  held responsible is clearly within the 15 and 50  kilograms which would obviously affect the  implications of the guidelines.


35
[Sent. Tr. Vol. 16 p.14-15]


36
It is clear from this excerpt that the district judge based his calculations on the evidence in  the record, and that he did not simply restate  the government's calculations set forth in the  pre-sentence report without first scrutinizing  them. Rather, he determined that the government's calculations were correct, and in fact were quite  conservative. (Recall Blake's testimony that he  supplied Johnson with between 35 and 45 kilograms  of cocaine.) Johnson correctly notes that there  could be some problem if the district judge  unwittingly relied on the recommended  calculations of the pre-sentence report thinking  that they were non-partisan conclusions, or if he  failed to scrutinize them in any way. But  "district judges have the ability to read a pre-  sentence report without being improperly  influenced." United States v. Sifuentez, 30 F.3d  1047, 1049 (9th Cir. 1994) (emphasis in  original). In this case, not only was the  district judge made aware of the government's  authorship of the calculations, he based his  adoption of these figures on an independent  review of the record.


37
Importantly, the Probation Department's substantial reliance on the government's position  does not mean that the information on which it  relied or the calculations that it performed were  inaccurate; it simply means that the Probation  Department also believed that there was a sufficient basis for these calculations. Notably, Johnson fails to show that there was insufficient  evidence to support the district court's  calculations, or that the evidence on which the  calculations were based is unworthy of credence;  rather, his sole complaint is with the PSR's  conformity with the government's view. Because  Johnson fails to show that the district court's  determinations were incorrect or that they were  based on unreliable evidence, we conclude that  the district court did not clearly err in finding  that Johnson should be held responsible for  between 15 and 50 kilograms of cocaine.


38
For all of these reasons, we affirm.



Notes:


1
 Both Hagenkord and Shultz pleaded guilty to one  count of conspiracy to distribute and possess  with intent to distribute in excess of five  kilograms of cocaine, in violation of 21 U.S.C.  sec.sec. 841(a)(1) & 846.


2
 Although at first glance this statement may not  appear to be hearsay, the parties agree that  Hagenkord was paraphrasing Blake, and that the  statement was indeed hearsay.


3
 However, in at least one federal circuit,  deliberate misrepresentations to the district  court that no Jencks material exists precludes  harmless error analysis. United States v.  DeFranco, 30 F.3d 664, 667 (6th Cir. 1994).


4
 The present case is much like the one we faced in  United States v. Starnes, 644 F.2d 673, 680 (7th  Cir. 1981). There, we held that the defendants  forfeited their argument that the prosecutor  failed to provide Brady material where the  prosecutor denied having such material and the  defendant failed to explore the issue by cross-  examining government agents or seeking a hearing.


5
 The record supports Johnson's contention that the  Probation Department relied on the government's  calculations of drug quantities, as Kanter  specifically stated so during the sentencing  hearing. Johnson argued before the district court  (but not to this court) that the only reliable  evidence showed that he was responsible for 4.5  kilograms of cocaine, thereby giving him a base  offense level of 30.


