Full opinion text
ILANA DIAMOND ROVNER, Circuit Judge. Appellants Kenneth Choice, Mark Cox, Bahman Mansoori, Mohammad Mansoori, and Terry Young were collectively convicted of conspiracy to possess with intent to distribute cocaine, cocaine base and heroin. Cox and Young were also convicted of possession of cocaine with the intent to distribute; Mohammad Mansoori was convicted of engaging in monetary transactions involving funds derived from criminal activity; and Young was convicted of money laundering. We affirm the appellants’ convictions but, based on certain errors at sentencing, vacate their sentences and remand for re-sentencing in conformity with this opinion. I. On October 31, 1996, a drug transaction many months in the planning finally came to pass. Several members of the Chicago street gang, Traveling Vice Lords (“TVL”), who were engaged in narcotics trafficking had organized a drug deal that, unbeknownst to them, would be captured on recorded telephone conversations obtained through court-authorized wiretaps. On that date, TVL leader Terry Young had arranged for TVL member Timothy White to purchase a kilogram of cocaine for resale from Mark Clemons. Young’s right-hand man, Kenneth Choice, was assigned to transfer the cocaine from White to another TVL member, Terry Bronson, who would keep it until Mark Cox came to pick it up for resale on the street. Once Bronson was in possession of the cocaine, the police began to follow his car. A chase ensued that finally ended with Bronson crashing his car into a garage and fleeing the scene of the accident without the cocaine, which the police officers seized. Arrests of the individuals who had participated in the narcotics trafficking ensued. The evidence at trial revealed that each of the appellants participated in a conspiracy to distribute narcotics in a different capacity. Mohammad Mansoori was not a member of TVL, but along with his brother, Bahman, distributed drugs and guns to Young. Young, Cox, and Choice were all members of TVL. They used the gang to plan highly organized drug transactions that culminated in street-level sales of cocaine and heroin at locations controlled by the gang. Young, a high-ranking TVL member, was in charge of the drug sales. Young obtained drugs and guns from Mohammad and Bahman Mansoori and then distributed both (the drugs for resale, and the firearms for protection) among various members of the gang. He assigned other gang members to certain locations where they carried out their sales. Choice worked directly for Young within the gang, picking up and delivering drugs for various TVL members. Cox also worked directly under Young, managing a large area of drug distribution locations. Both Mohammad Mansoori and Young purchased property with earnings from the drug enterprise. Mansoori made several large cash payments to contractors for a house he was having built in Highland Park. He had confessed to an accountant and an IRS agent that he did not receive any money from his legitimate enterprises. The police had also stopped Mansoori and seized about $11,000 in cash made from a suspected drug transaction. Young had purchased a house through a nominee purchaser, Lovell Nabors. Although Nabors signed a lease with purchase option for the house, he used Young’s money to make the purchase and understood that the house was actually Young’s. An IRS agent testified that he did not think that Young could have purchased the property with his legitimate sources of income. The jury convicted appellants of all charges, and this appeal arises from the convictions and the lengthy sentences that the district court imposed pursuant to those convictions. II. A. Wiretap Order On four occasions in late 1996 and early 1997, then-Chief Judge Marvin Aspen of the Northern District of Illinois entered orders authorizing the government to monitor various telephone numbers which, the government believed, the defendants were using to conduct their narcotics business. The orders indicated that the conversations intercepted from these telephone numbers were expected to reveal: (1) the identities of individuals possessing with intent to distribute and distributing controlled substances; (2) the locations where the controlled substances were distributed and stored; (3) the methods by which the controlled substances were distributed and drug proceeds are distributed; (4) the dates, times and manner of the transportation, receipt, storage, distribution and delivery of the controlled substances and proceeds; (5) the nature and scope of the conspiracy; and (6) the identities and roles of unidentified conspirators. Appellants’ Joint Appendix (“App.”) 228-29, 237-38, 245-46, 254. Each order also compelled the government to minimize (i.e., limit) the interception of conversations that did not relate to the government’s investigation. Monitoring of wire conversations must terminate immediately when it is determined that the conversation is unrelated to communications subject to interception under Chapter 119, Title 18, United States Code. Interception must be suspended immediately when it is determined through voice identification, physical surveillance, or otherwise, that none of the named interceptees or any of their'confederates, when identified, are participants in the conversation unless it is determined during the portion of the conversation already overheard that the conversation is criminal in nature.... App. 232, 241, 248-49, 257; see 18 U.S.C. § 2518(5). Conversely, however, the orders also permitted the individual monitoring to spot check any minimized conversation to ensure that the participants had not turned their discussion to illicit matters within the scope of the investigation. (“If the conversation is minimized, the monitoring individual shall spot check to ensure that the conversation has not turned to criminal matters.”). App. 232, 241, 249, 257-58. Pursuant to these orders, the government intercepted more than 3,500 telephone conversations. In order to determine whether a given conversation fell within the scope of the intercept order or instead concerned matters unrelated to the investigation, the government would initially intercept the conversation for a period of two minutes. If the monitoring individual determined that the conversation was beyond the scope of authorized surveillance, the interception would cease at the end of the two-minute period in compliance with the minimization requirement of the wiretap orders. However, if that conversation lasted for more than another minute or so, the monitoring individual would re-intercept the conversation and perform a follow-up spot check to confirm that the conversation had not progressed into the scope of authorized surveillance. In practice, this meant that all telephone calls under two minutes in length were intercepted (whether relevant to the investigation or not) and that one or more two-minute segments of longer conversations were also intercepted, even when those conversations were irrelevant to the investigation. A summary prepared by the government indicates that of all the calls intercepted: 565 conversations were identified as criminal in nature and so were not minimized; 1,791 conversations were not pertinent to the investigation but were not minimized because they lasted no more than two minutes; and another 366 were not pertinent and exceeded two minutes in length, and of these nearly all (362) were minimized. R. 267 at 21. In advance of trial, the defendants moved to suppress all of the intercepted conversations, contending that the government had not complied with the minimization requirement and, as a result, had unnecessarily and inappropriately eavesdropped on a number of conversations that were beyond the scope of its investigation. Judge Lindberg denied the motion. Although the judge agreed that the government had intercepted a number of conversations, or portions of conversations, that were beyond the scope of the wiretap orders, he did not believe that the government’s agents had listened to more of the conversations than necessary-in order to determine that they were irrelevant: [I]t is understandable that a fair amount of material not pertinent to the investigation wound up being intercepted in this investigation. Many of the conversations were under two minutes in length, and so did not require minimization. The individuals conversing often did so in an ambiguous, guarded, and possibly coded manner so that more of the conversations had to be intercepted to later sort out what in fact they were talking about. The Government had evidence that defendant Terry Young was the head of a major drug ring justifying more extensive interception. And the authorizing judge was supervising the electronic surveillance in an ongoing manner, receiving reports on it at ten day intervals. R. 335 at 2. At trial, the government introduced approximately 300 of the tape recordings into evidence. Because these recordings captured the defendants discussing narcotics transactions, they proved to be some of the most direct and damning evidence in the prosecution’s arsenal. On appeal, the defendants initially argue that the wiretap orders, by virtue of the provision allowing periodic spot checks of any minimized conversation “to ensure that the conversation has not turned to criminal matters,” violated their statutory and constitutional rights. Title III of the Omnibus Crime Control and Safe Streets Act of 1968, 18 U.S.C. § 2510 et seq., includes a mandate that “[ejvery [intercept] order and extension thereof shall contain a provision that the authorization to intercept ... shall be conducted in such a way as to minimize the interception of communications not otherwise subject to intereeption under this chapter .... ” 18 U.S.C. § 2518(5). Although the intercept orders in this case included a minimization requirement, the defendants believe that this provision of the orders was rendered virtually meaningless as a result of the orders’ additional provision that “the monitoring individual shall spot check to ensure that the conversation has not turned to criminal matters.” App. 232, 241, 249, 257-58 (emphasis added). They find the spot-check provision problematic in two respects: (1) the provision imposed no limits on the frequency or duration of spot checks; and (2) because the provision referred broadly to “criminal matters” rather than to the specific criminal activities for which Judge Aspen had authorized interception, the orders permitted the government to check each and every minimized conversation for any discussion of criminal activity, even criminal activity that was unrelated to the government’s investigation. Because the defendants did not make this particular challenge below, our review is for plain error alone, see United States v. Williams, 272 F.3d 845, 854-55 (7th Cir.2001), cert. denied, — U.S.-, 122 S.Ct. 1339, 152 L.Ed.2d 243 (2002), and we find no such error in the terms of the orders. Express limits on the frequency and duration of spot checks may well be impractical, as neither the government nor the authorizing court can know in advance how easy it will be for the monitoring agent to discern whether any given intercepted conversation concerns a subject within the scope of the investigation or not. A conversation may be short and to the point or long and meandering; and a conversation may begin on a non-pertinent topic but switch to a pertinent subject in short order. Use of code language, which as the district judge recognized is common among narcotics traffickers, can make quick assessments of the pertinence of a conversation difficult. So we cannot say that Judge Aspen erred when he refrained from placing a one-size-fits-all limitation on either the frequency or duration of followup spot checks or that Judge Lindberg plainly erred when he declined to suppress the results of the surveillance for want of such a limitation. Nor do we think that the provision’s generalized reference to “criminal matters” plainly rendered the spot-check provision overbroad. When read in context with the other terms of the wiretap orders, that language did not give the government license to monitor all minimized conversations for any mention of criminal activity, whether related to the investigation or not. The orders specifically identified the type of evidence that the authorized intercepts were intended to capture. App. 228-29, 237-38, 245-46, 254. Furthermore, the orders required the government to stop monitoring a conversation “immediately” if the conversation turned out not to constitute “communications subject to interception under [Title III.]” App. 232, 241, 248, 257. The orders also acknowledged that Title III allowed for the interception and disclosure only of “those communications relevant to the pending investigation-” App. 232, 241, 248, 257. Indeed, the government’s instructions to its monitoring agents noted that “[w]e do not have authorization to overhear evidence concerning the commission or planning of crimes other than those [specified previously in the instructions] as illegal activities.” R. 267 Ex. A at 7; see also id. at 3-4 (specifying illegal activities as to which interception permitted). Notwithstanding the language of the spot-check provision, then, the overall terms of the orders made reasonably clear that the government was permitted to check intercepted conversations solely for discussions pertinent to the government’s investigation, the nature and scope of which the face of the orders made clear. Any impermissible overbreadth in the spot-check provisions of the orders was not plain. The defendants’ second challenge focuses on the adequacy of the government’s efforts to comply with the minimization requirement. What the minimization requirement means, essentially, is that once the monitoring agent has had a reasonable opportunity to assess the nature of an intercepted communication, he or she must stop monitoring that communication if it does not appear relevant to the government’s investigation. In this case, the government’s instructions to the monitoring agents indicated that they could listen to all calls involving one of the individuals named in the instructions “for a reasonable time, usually not in excess of two minutes, to determine whether the conversation concerns criminal activities.” Id. at 5. In practice, the agents monitored the entirety of all calls under two minutes in length (some 1,791 calls, 103 of which were in Farsi). Moreover, calls in excess of two minutes that were deemed non-pertinent after the initial two-minute assessment were, per the instructions, periodically reassessed (again for up to two minutes at a time) at intervals of at least one minute. Id. at 5-6. So, theoretically, an agent could listen to the first two minutes of a conversation, decide it was non-pertinent, turn off the listening and recording devices for a minute, then turn them back on and listen to the conversation for another two minutes, and so on — and in this way monitor as much as two-thirds of a non-pertinent conversation. The defendants argue that because the government’s agents listened to each call for a period of two minutes to determine initially whether or not the conversation fell within the scope of the wiretap orders, and because they performed periodic, two-minute spot-checks on minimized calls, there was no real minimization in practice. A court assessing the sufficiency of the government’s efforts in this regard must ultimately decide whether the steps that agents have taken to minimize the interception of communications unrelated to the investigation were objectively reasonable given the circumstances confronting the agents. See Scott v. United States, 436 U.S. 128, 137, 98 S.Ct. 1717, 1723, 56 L.Ed.2d 168 (1978). Although the adequacy of the government’s minimization efforts necessarily depends on the facts of each case, relevant considerations include the kind and scope of criminal enterprise that the government was investigating, the thoroughness of the government’s efforts to ensure that nonpertinent calls will be minimized, the extent to which the government could have foreseen that certain types of conversations would be innocuous and thus subject to minimization, use of code, and the extent to which the authorizing judge oversaw the interception efforts. United States v. Quintana, 508 F.2d 867, 874-75 (7th Cir.1975); see also United States v. Charles, 213 F.3d 10, 22 (1st Cir.), cert. denied, 531 U.S. 915, 121 S.Ct. 272, 148 L.Ed.2d 198 (2000); United States v. Bankston, 182 F.3d 296, 307 (5th Cir.1999), judgment rev’d on other grounds by Cleveland v. United States, 531 U.S. 12, 121 S.Ct. 365, 148 L.Ed.2d 221 (2000); United States v. Williams, 109 F.3d 502, 507 (8th Cir.), cert. denied, 522 U.S. 917, 118 S.Ct. 303, 139 L.Ed.2d 234 (1997). “[W]here an investigation involves a drug ring of unknown proportion, as in this case, ‘the need to allow latitude to eavesdroppers is close to its zenith.’ ” Charles, 213 F.3d at 22, quoting United States v. Hoffman, 832 F.2d 1299, 1308 (1st Cir.1987). We review the district court’s minimization assessment for clear error. United States v. Moody, 977 F.2d 1425, 1433 (11th Cir.1992), cert. denied, 507 U.S. 1052, 113 S.Ct. 1948, 123 L.Ed.2d 653 (1993); Bankston, 182 F.3d at 306. We are not inclined to view the government’s overall approach to minimization in this case as insufficient. The government was investigating what the district judge described as a “major drug ring.” R. 335 at 2. Narcotics traffickers are often aware that their conversations might be overheard or intercepted, and so may choose their words carefully. In this case, Judge Lindberg found that “[t]he individuals conversing often did so in an ambiguous, guarded, and possibly coded manner .... ” Id. Consequently, the individuals monitoring such conversations cannot be expected to make snap judgments as to whether the subject of the conversation is within the scope of the intercept order. See Quinta-na, 508 F.2d at 874 (“It is all well and good to say, after the fact, that certain conversations were irrelevant and [monitoring] should have been terminated. However, the monitoring agents are not gifted with prescience and cannot be expected to know in advance what direction the conversation will take.”) (internal quotation marks and citations omitted). A number of other courts have found that two to three minutes is a reasonable period of time within which to make an initial judgment as to the pertinence of a conversation. See United States v. Ozar, 50 F.3d 1440, 1448 (8th Cir.), cert. denied, 516 U.S. 871, 116 S.Ct. 193, 133 L.Ed.2d 128 (1995); United States v. Homick, 964 F.2d 899, 903 (9th Cir.1992); United States v. Willis, 890 F.2d 1099, 1102 (10th Cir.1989); United States v. Losing, 560 F.2d 906, 909 n. 1 (8th Cir.), cert. denied, 434 U.S. 969, 98 S.Ct. 516, 54 L.Ed.2d 457 (1977); United States v. Armocida, 515 F.2d 29, 45 (3d Cir.), cert. denied, 423 U.S. 858, 96 S.Ct. 111, 46 L.Ed.2d 84 (1975); see also Bynum v. United States, 423 U.S. 952, 954, 96 S.Ct. 357, 358, 46 L.Ed.2d 277 (1975) (Brennan, J., dissenting from denial of cer-tiorari) (noting that brief calls — apparently those of less than three minutes in duration — will generally not be subject to minimization). Moreover, because conversations among traffickers, as among others, may bounce among a variety of topics, periodic spot-checking of minimized conversations is not unreasonable either. See Ozar, 50 F.3d at 1448. Thus, the general parameters under which the government conducted the monitoring here were not inherently suspect. Moreover, we note that the government in the course of its electronic surveillance submitted periodic reports to Judge Aspen, a circumstance that suggests it conducted the surveillance in good faith. See Quintana, 508 F.2d at 875. But whether, in practice, the government’s actual minimization efforts were sufficient is not a point that we need to resolve, ultimately. The adequacy of the government’s minimization efforts typically cannot be determined in a generalized fashion. See Scott, 436 U.S. at 140-41, 98 S.Ct. at 1724-25. Yet the defendants have framed their challenge in very broad terms. They appear to suggest, for example, that it was unreasonable for monitoring agents to listen to all calls for an initial two-minute period, apparently on the assumption that a speedier assessment as to the pertinence of the calls was possible in at least some instances. And, indeed, perhaps some of the intercepted conversations did lend themselves to simple and quick categorization as pertinent or non-pertinent, while others required a full two minutes or more to assess. See id. at 140-43, 98 S.Ct. at 1724-26; cf. Quintana, 508 F.2d at 874 (if a pattern of innocent conversations emerges, agents should cease monitoring such conversations; but such patterns will not always be identifiable). The point is, however, that we cannot know whether this is true without examining at least a sampling of the intercepted calls. Likewise, whether the agents performed spot checks at intervals that were too frequent, and whether they listened for too long when they made those checks, is not a question that can be answered responsibly in the abstract. If, after a review of the intercepts, the defendants believed that the government’s eavesdropping was too intrusive and that a greater degree of minimization was warranted, then it was incumbent upon them to identify at least a sample of intercepted calls that proves their point. This they have not done. If the defendants were to prevail on their challenge, the appropriate relief likely would be to suppress any conversation or conversations that were inappropriately monitored. See 18 U.S.C. § 2518(10)(a)(iii); Charles, 213 F.3d at 22 (partial suppression of those conversations intercepted improperly is the usual remedy for inadequate minimization efforts; wholesale suppression of all intercepted conversations is reserved for the “particularly horrendous case”), quoting Hoffman, 832 F.2d at 1309; Ozar, 50 F.3d at 1448; see also United States v. Baltas, 236 F.3d 27, 32 (1st Cir.), cert. denied, 532 U.S. 1030, 121 S.Ct. 1982, 149 L.Ed.2d 773 (2001); United States v. Dorfman, 542 F.Supp. 345, 394-95 (N.D.Ill.1982), judgment affd sub nom. United States v. Williams, 737 F.2d 594 (7th Cir.1984), cert. denied, 470 U.S. 1003, 105 S.Ct. 1354, 1355, 84 L.Ed.2d 377 (1985). Judge Lindberg pointed out that the defendants had not identified any particular conversation that should have been minimized but was not or that should have been minimized to a greater degree than it was. R. 335 at 2. Even on appeal, the defendants do not identify any such conversation. Nor do the defendants identify any concrete harms resulting from the admission of conversations which, in their view, should have been suppressed for want of appropriate minimization. Consequently, we have been deprived of the requisite basis for assessing the government’s minimization efforts. For that reason, we need not, in the end, reach the merits of the minimization argument. B. Anonymous Jury On the government’s motion, and over the defendants’ objections, the district court decided not to disclose the names or the home and work addresses of prospective and empaneled jurors to the parties, the public, or the media — a step that resulted in an anonymous jury. Judge Lind-berg had initially denied the government’s request for juror anonymity, remarking that he did not “see any need for it.” R. 750, 1/12/98 Transcript (“Tr.”) 27. After entertaining further argument on the matter, however, the judge acceded to the request. He cited the following circumstances in support of his ruling: (1) the defendants were involved in organized, violent street crime that had “elements of what is traditionally called organized crime,” (2) with access to some 200 firearms, the defendants had the “capacity to harm jurors,” (3) allegedly, some of the witnesses and their families had been threatened, (4) the defendants were subject to lengthy terms of incarceration and stiff monetary penalties if convicted, and (5) there would likely be press coverage— “perhaps not extensive, but significant, publicity” — regarding the case. Id. at 116-17. “So it’s not the fact that it’s a drug case or a firearms case,” the judge explained, “but it is the fact that there appears to be organized activity on the part of the defendants and their associates and families that warrants the prophylaxis of juror anonymity.” Id. at 117-18. Shortly before jury selection commenced, Judge Lindberg disavowed any reliance upon threats against witnesses and their families, explaining that his principal concerns about the prospect of interference with jurors were based on his experience with another trial involving the Gangster Disciples, a gang unrelated to the Traveling Vice Lords. R. 754-1, 1/20/98 Tr. at 6. This left the organized-crime aspect of the case as the sole basis for the court’s decision in favor of juror anonymity. In the midst of jury selection, defendant Young’s counsel asked the court to give the members of the venire an instruction indicating that their names and addresses were being withheld for reasons other than their own safety, so as to allay any suspicions among prospective jurors that their anonymity might otherwise arouse and to thereby minimize the potential prejudice to the defendants. See United States v. Crockett, 979 F.2d 1204, 1216-17 (7th Cir. 1992), cert. denied, 507 U.S. 998, 113 S.Ct. 1617, 123 L.Ed.2d 176 (1993). The court agreed to give an instruction to the effect that the jurors’ identifying information was being withheld in order to prevent the media from contacting them. R. 754-8, 1/22/98 Tr. 380. However, when the full venire was assembled for final questioning, the judge neglected to give the instruction, and the parties did not remind him to do so. The defendants argue now, as they did below, that the circumstances confronting the court did not warrant an anonymous jury and, that the court therefore abused its discretion in empaneling such a jury. Noting that the district court also failed to deliver an appropriate ameliorative instruction, they contend that the defense was so prejudiced by the anonymity as to necessitate a new trial. Although we agree that the court abused its discretion in empaneling an anonymous jury, see United States v. DiDomenico, 78 F.3d 294, 301 (7th Cir.), cert. denied, 519 U.S. 1006, 117 S.Ct. 507, 136 L.Ed.2d 398 (1996) (decision to empanel anonymous jury reviewed for abuse of discretion), in view of the district court’s careful voir dire of prospective jurors and the overwhelming evidence of the defendants’ guilt, we find the error harmless. Empaneling an anonymous jury is an extreme measure that is warranted only where “ ‘there is strong reason to believe the jury needs protection.’ ” Crockett, 979 F.2d at 1215, quoting United States v. Paccione, 949 F.2d 1183, 1192 (2nd Cir.1991), cert. denied, 505 U.S. 1220, 112 S.Ct. 3029, 120 L.Ed.2d 900 (1992). “An anonymous jury raises the specter that the defendant is a dangerous person from whom the jurors must be protected, thereby implicating the defendant’s constitutional right to a presumption of innocence.” United States v. Ross, 33 F.3d 1507, 1519 (11th Cir.1994), cert. denied, 515 U.S. 1132, 115 S.Ct. 2558, 132 L.Ed.2d 812 (1995); see also United States v. Sanchez, 74 F.3d 562, 564 (5th Cir.1996); United States v. Edmond, 52 F.3d 1080, 1090 (D.C.Cir.) (per curiam), cert. denied, 516 U.S. 998, 116 S.Ct. 539, 133 L.Ed.2d 443 (1995); United States v. Scarfo, 850 F.2d 1015, 1023-26 (3rd Cir.), cert. denied, 488 U.S. 910, 109 S.Ct. 263, 102 L.Ed.2d 251 (1988); United States v. Thomas, 757 F.2d 1359, 1363-65 (2nd Cir.1985), cert. denied, 474 U.S. 819, 106 S.Ct. 66, 67, 88 L.Ed.2d 54 (1985), and cert. denied., 479 U.S. 818, 107 S.Ct. 78, 93 L.Ed.2d 34 (1986). Juror anonymity also deprives the defendant of information that might help him to make appropriate challenges' — in particular, peremptory challenges — during jury selection. DiDomenico, 78 F.3d at 301; Edmond, 52 F.3d at 1090. Yet, neither the right to a presumption of innocence nor the right to exercise peremptory challenges is a constitutional absolute; each, at times, must yield to the legitimate demands of trial administration and court-room security so long as steps are taken to ensure that the defendant receives a fair trial. Id. A court weighing the need for an anonymous jury must therefore balance the defendant’s interest in preserving the presumption of innocence and in conducting a useful voir dire against the jurors’ interest in their own security and the public’s interest in having a jury assess the defendant’s guilt or innocence impartially. United States v. Amuso, 21 F.3d 1251, 1264 (2nd Cir.), cert. denied, 513 U.S. 932, 115 S.Ct. 326, 130 L.Ed.2d 286 (1994); accord Edmond, 52 F.3d at 1090. Factors bearing on the propriety of an anonymous jury include the defendant’s involvement in organized crime; his participation in a group with the capacity to harm jurors; whether he previously has attempted to interfere with the judicial process; the severity of the punishment that the defendant would face if convicted; and whether publicity regarding the case presents the prospect that the jurors’ names could become public and expose them to intimidation or harassment. Sanchez, 74 F.3d at 564, quoting United States v. Krout, 66 F.3d 1420, 1427 (5th Cir.1995), cert. denied, 516 U.S. 1136, 116 S.Ct. 963, 133 L.Ed.2d 884 (1996); United States v. Darden, 70 F.3d 1507, 1532-33 (8th Cir.1995), cert. denied, 517 U.S. 1149, 116 S.Ct. 1449, 134 L.Ed.2d 569 (1996), and cert. denied, 518 U.S. 1026, 116 S.Ct. 2567, 135 L.Ed.2d 1084 (1996); Edmond, 52 F.3d at 1091; Ross, 33 F.3d at 1520. We do not believe that the circumstances in this case warranted an anonymous jury. Although the case did involve elements of organized crime, “something more” than the organized-crime label is required in order to justify juror anonymity. As we explained in Crockett: “[SJomething more” can be a demonstrable history or likelihood of obstruction of justice on the part of the defendant or others acting on his behalf or a showing that trial evidence will depict a pattern of violence by the defendant! ] and his associates such as would cause a juror to reasonably fear for his own safety. 979 F.2d at 1216, quoting United States v. Vario, 943 F.2d 236, 241 (2nd Cir.1991), cert. denied, 502 U.S. 1036, 112 S.Ct. 882, 116 L.Ed.2d 786 (1992). In this case, the district court made no finding that the defendants had a history of intimidating witnesses or otherwise obstructing justice or that they were likely to do so in connection with this trial. Cf. DiDomenico, 78 F.3d at 301-02 (defendants were connected to organized crime syndicate that had history of bribery and intimidation); Edmond, 52 F.3d at 1091-92 (one of defendants in narcotics conspiracy prosecution was also charged with murder, other defendants were implicated in that murder as well, and there was some evidence of planned and attempted witness intimidation); Crockett, 979 F.2d at 1216 (evidence indicated that one potential witness had been murdered and that attempts had been made to influence or intimidate other witnesses). True, the defendants may have had the ability to intimidate jurors through associates who were not incarcerated, but that is true of many defendants. What demonstrates the need for jury protection is not simply the means of intimidation, but some evidence indicating that intimidation is likely. See, e.g., Darden, 70 F.3d at 1532-33; Ross, 33 F.3d at 1520-21; Vario, 943 F.2d at 240, 241. No such evidence is present here. Nor is there evidence that the defendants had engaged in a pattern of violence unusual enough to cause jurors to fear for their safety. Compare, e.g., Amuso, 21 F.3d at 1264-65 (indictment alleged that defendant was responsible for crimes of extreme violence, including murders of government witnesses). Although the narcotics conspiracy in this case embraced a large-scale, gang-related operation with ready access to firearms, this is regrettably not uncommon in the drug trade. See, e.g., United States v. Jones, 214 F.3d 836, 838 (7th Cir.2000) (“guns are common in the drug trade”). The government has pointed to no evidence of violence of such a degree as to make this case unusual. The publicity surrounding the case was by no means extensive. Similarly, the fact that the defendants faced lengthy prison terms if convicted is hardly unusual — this is almost always true when a defendant has dealt in large quantities of narcotics. In short, that the defendants had the ability and incentive to threaten jurors, without additional evidence indicating that they were likely to act on that ability and incentive, was not enough to justify the unusual step of juror anonymity. After a complete review of the record, however, we conclude that the error was harmless. We recognize that the Fifth Circuit has suggested that an erroneous decision to empanel an anonymous jury is not harmless where almost none of the pertinent factors supported that decision, but in so opining, that court left open the possibility that a harmless error analysis might be appropriate in a closer case. Sanchez, 74 F.3d at 565. Notwithstanding our disagreement with the district court’s decision, we believe this to be a closer case than our colleagues on the Fifth Circuit confronted in Sanchez. The conspiracy charged in this case did take on elements of organized crime; the defendants and their unindicted co-conspirators did use weapons and violence in furtherance of the conspiracy; the defendants faced very long prison terms upon conviction; and there had been some pre-trial publicity regarding the case. Although these circumstances were not, by themselves, sufficient to justify an anonymous jury, they demonstrate that the record was by no means devoid of a basis for concern for the security of the jurors. At the same time, Judge Lindberg conducted an extremely thorough voir dire of prospective jurors in this case over the course of three and one-half days. Juror anonymity is most concretely felt during the selection of the jury, when the withholding of identifying information makes it more difficult for the defense (and for that matter the prosecution) to make intelligent decisions as to which prospective jurors should be challenged or stricken peremptorily. See DiDomenico, 78 F.3d at 301; Crockett, 979 F.2d at 1216. A conscientious voir dire compensates for this disadvantage by rooting out biases against the defendant or as to the issues presented in the case. Id. at 1216; see also Edmond, 52 F.3d at 1092-93; Ross, 33 F.3d at 1520. The defendants have identified no aspect in which the district court’s voir dire was wanting, and our own review of the trial transcript satisfies us that the voir dire was “searching and thorough.” Crockett, 979 F.2d at 1216. In this way, the defendants’ right to an unbiased jury was protected. Moreover, the courts instructions to the jury during both voir dire and the trial emphasized that the defendants were presumed innocent and that the government bore the burden of proving them guilty beyond a reasonable doubt. See Crockett, 979 F.2d at 1216; R. 350 at 5 ¶ 10; R. 351 at 5 ¶ 10; R. 352 at 5 ¶ 10; Tr. 15, 16, 5323. Potential prejudice would have been further alleviated by an appropriate cautionary instruction regarding the anonymity of the jury. See, e.g., Crockett, 979 F.2d at 1216-17. However, despite Judge Lindberg’s expressed willingness to give such an instruction, neither Young nor any of the other defendants reminded him to do so. Consequently, the defendants cannot properly complain about that omission now. See Varhol v. National R.R. Passenger Corp., 909 F.2d 1557, 1567-68 (7th Cir.1990) (en banc) (per curiam); Palmquist v. Selvik, 111 F.3d 1332, 1343 (7th Cir.1997). In view of the careful voir dire, together with what we believe to be the overwhelming evidence of defendants’ guilt, we can discern no concrete way in which the anonymous jury deprived the defendants of a fair trial. C. Admission of Officer Cronin’s Testimony Over the objections of the defense, the district court permitted Chicago Police Officer Michael Cronin, a gang specialist, to give opinion testimony regarding the history, leadership, and operations of the Traveling Vice Lords. Cronin testified that the TVLs controlled narcotics distribution on the west side of Chicago by means of a series of distribution loci known as “drug spots.” Tr. 1574. Cronin went on to identify a number of locations that were, in his opinion, controlled by the TVLs, to describe how a “drug spot” operates, and to recount disputes between various factions of the Vice Lords over drug turf. Tr. 1575-82. Cronin was also involved in the investigation that culminated in this prosecution; and he testified as a fact witness regarding surveillance in which he had participated, arrests he had made, various items of evidence that had been recovered, and to a statement that Cox made following his arrest. Tr. 1585-1628. Although the defendants do not dispute Cronin’s qualifications as a gang expert, they maintain that his testimony as to the TVLs’ involvement in narcotics distribution amounted to inadmissible hearsay that was prejudicial in the sense that it related to a central issue in the case. Whereas the defendants posited that their narcotics activities reflected multiple, unrelated conspiracies, it was the government’s theory that the defendants were involved in a unitary conspiracy that used the TVL organization to distribute cocaine and heroin. That theory was reflected in the superseding indictment, e.g., R. 133 at 2-3, as well as the prosecution’s opening and closing statements, Tr. 19-20, 4982. In the defense view, Cronin’s testimony as to the operation of the TVL drug distribution network went beyond the bounds of appropriate expert testimony, because rather than helping the jury “to understand the evidence or to determine a fact in issue,” Fed.R.Evid. 702, “it simply told them that if the defendants were associated with the TVL, they were part of a unitary conspiracy.” Defendants’ Joint Opening Br. at 36. The defendants argue alternatively that even if Cronin’s testimony qualified for admission under Rule 702, its potential for prejudicing the defense exceeded its probative value and therefore it should have been excluded pursuant to Federal Rule of Evidence 403. Non-expert, eyewitness testimony regarding the nature and operation of the TVL distribution network was perfectly comprehensible, the defendants insist, and so there was no need for expert testimony to help the jury understand this evidence. At the same time, they argue, the prejudicial effect of Cronin’s testimony was “immense.” Defendants’ Joint Opening Br. at 39. Given his dual role as both a fact and an opinion witness, the defense postulates that the jury may have failed to appreciate when Cronin was testifying to facts based on his personal knowledge and when he was merely offering his opinion, and consequently may have given his opinions undue weight. This danger was particularly acute, the defendants reason, in view of the fact that the only eyewitness testimony concerning TVL operations came from former drug dealers who had an obvious incentive to cooperate with the government. Thus, the jury may have improperly looked to Cronin’s opinions as “facts” which corroborated the testimony of these less-than-upstanding witnesses. Although the district court gave a standard instruction admonishing the jury that it was not obliged to accept the opinion testimony of experts, Tr. 5328-29, the defendants point out that the instruction did not specifically advise the jury that Cronin’s testimony regarding the operation of the TVL narcotics distribution apparatus constituted opinion, rather than fact, testimony. We find no abuse of discretion in the district court’s decision to permit Cronin to testify as an expert. The average juror is unlikely to be familiar with the operations of narcotics traffickers or of street gangs. See, e.g., United States v. Anderson, 61 F.3d 1290, 1297 (7th Cir.) (drug trafficking), cert. denied, 516 U.S. 1000, 116 S.Ct. 543, 133 L.Ed.2d 446 (1995); United States v. Johnson, 28 F.3d 1487, 1496-98 & nn. 9, 10 (8th Cir.1994) (drug trafficking and gangs), cert. denied, 513 U.S. 1098, 115 S.Ct. 768, 130 L.Ed.2d 664 (1995), and cert. denied, 513 U.S. 1195, 115 S.Ct. 1263, 131 L.Ed.2d 142 (1995). Cronin’s testimony supplied the jury with useful background concerning the history and structure of the TVLs, as well as with their involvement in narcotics activities. At the same time, Cronin’s testimony did not invite the jury to conclude that membership in the TVLs equated with participation in the charged conspiracy, as the defendants suggest. We can find nothing in Cronin’s testimony which suggested that all TVL members were involved in criminal activity generally or narcotics trafficking in particular. On the contrary, Cronin agreed on cross-examination that “membership in the Vice Lord Nation is not a crime,” Tr. 1561, and that membership in a street gang “does not necessarily indicate that you are involved in illegal activities,” Tr. 1643. See also Tr. 1733. In the same vein, the district court instructed the jury that “[i]t is not illegal to be a member of or associated with the Traveling Vice Lords.” Tr. 5325. Nor do we think it likely that Cronin’s dual role as expert and fact witness would have led the jury to be confused as to which aspects of his testimony were opinions and which were factual in nature. Although we have acknowledged that there is a greater danger of undue prejudice to the defendants when a witness testifies as both an expert and a fact witness, United States v. Doe, 149 F.3d 634, 637 (7th Cir.), cert. denied, 525 U.S. 914, 119 S.Ct. 260, 142 L.Ed.2d 214 (1998), we have also indicated that a police officer may permissibly testify in both capacities, United States v. Lightfoot, 224 F.3d 586, 588-89 (7th Cir.2000), cert. denied, 532 U.S. 976, 121 S.Ct. 1611, 149 L.Ed.2d 476 (2001). The potential for prejudice in this circumstance can be addressed by means of appropriate cautionary instructions and by examination of the witness that is structured in such a way as to make clear when the witness is testifying to facts and when he is offering his opinion as an expert. See United States v. Lipscomb, 14 F.3d 1236, 1242 (7th Cir.1994); United States v. Foster, 939 F.2d 445, 453 (7th Cir.1991). In this case, the government structured its direct examination of Cronin in such a way as to separate his opinions as an expert from his factual observations as an occurrence witness, compare Tr. 1569-84 with Tr. 1586-1628; and both the objections that the defense posed at the transition from opinion to fact as well as the remarks that the district judge made in response to those objections served to highlight the distinction, see Tr. 1586-88. Cronin was also extensively voir dired by the defense as to the basis for his opinions, see Tr. 1529-32, 1542-64, which again made clear to the jury the distinction between the two aspects of his testimony. Finally, the court reminded the jurors that “the fact an expert has given an opinion does not mean that it is binding upon you or that your are obligated to accept the expert’s opinion as to the facts.” Tr. 5329. Under these circumstances, we see no real possibility that the jury may have been led to mistakenly credit Cronin’s opinions as facts. D. Jury Instruction — Conviction or Acquittal After outlining the two principal elements of the conspiracy charge for the jury, the district court gave the following pattern instruction: If you find from your consideration of all the evidence that both of these propositions [have] been proved beyond a reasonable doubt with regard to the defendant you are then considering, then you should find that defendant guilty. If, on the other hand, you find from your consideration of all of the evidence that either of these propositions has not been proved beyond a reasonable doubt as to the defendant you are then considering, then you should find that defendant not guilty. Tr. 5331. The court repeated this same instruction with respect to each count of the indictment. Tr. 5334, 5336-37, 5338-39. The defendants argue that the language of this instruction was flawed to the extent that it advised the jury that it “should” rather than “must” acquit a defendant if it found that the government had not proved the elements of the crime charged beyond a reasonable doubt. “Should,” in the defendants’ view, is a permissive term, suggesting that the jury had discretion whether or not to find a defendant not guilty even if the government had not met its burden of proof. Of course, if it is reasonably likely that the jury understood the instructions to permit conviction on something less than proof beyond a reasonable doubt, it constituted reversible error. See Victor v. Nebraska, 511 U.S. 1, 6, 114 S.Ct. 1239, 1243, 127 L.Ed.2d 583 (1994). However, the defendants did not object to the instruction in the district court, so we may reverse only if the flaw in the instruction, if any, amounts to plain error. E.g., United States v. Inglese, 282 F.3d 528, 536-37 (7th Cir.2002). Our opinion in United States v. Kerley, 838 F.2d 932 (7th Cir.1988), makes clear that the language at issue was not plainly erroneous. In that case as in this one, the defendant argued that the use of the term “should” gave the jury license to convict the defendant even if the government had not established his guilt beyond a reasonable doubt. We flatly rejected that argument: Least of the alleged trial errors is the judge’s having instructed the jury that they “should” rather than “must” acquit Kerley in the event the government had failed to prove his guilt beyond a reasonable doubt. “Must” is preferable; but it is hardly plausible that the jury supposed that while they “should” acquit Kerley if he was not guilty beyond a reasonable doubt, they didn’t have to acquit him if they didn’t want to. Juries know better than that. We add that the judge also said that the jury “should,” not “must,” convict Kerley if they found that he was guilty beyond a reasonable doubt. In context, “should” was imperative — not hortatory — throughout the instruction. Id. at 940. Although the defendants suggest that the Supreme Court’s opinions in Sullivan v. Louisiana, 508 U.S. 275, 113 S.Ct. 2078, 124 L.Ed.2d 182 (1993), and Victor have undermined our decision in Kerley, we disagree. The instruction at issue here did not mis-describe the burden of proof, as was the case in Sullivan, see 508 U.S. at 277-78, 113 S.Ct. at 2080-81. The jury was properly informed that the government was obliged to prove the defendants guilty beyond a reasonable doubt. Tr. 5323. Moreover, the Court in Victor described the constitutional question raised by flawed language regarding the burden of proof as “whether there is a reasonable likelihood that the jury understood the instructions to allow conviction based on proof insufficient to meet the Winship [reasonable doubt] standard.” 511 U.S. at 6, 114 S.Ct. at 1243; see In re Winship, 397 U.S. 358, 90 S.Ct. 1068, 25 L.Ed.2d 368 (1970). That is the very question we answered in Kerley vis á vis use of the term “should” — and we found it implausible that the jury believed acquittal was optional if the government failed to meet its burden of proof. 838 F.2d at 940; see also United States v. Ray, 238 F.3d 828, 834-35 (7th Cir.), cert. denied, 532 U.S. 1045, 121 S.Ct. 2014, 149 L.Ed.2d 1015 (2001). Accordingly, we find no plain error in the language of this instruction. E. Multiple Conspiracies Instruction As we have noted, it was the defense theory in this case that the defendants had not joined a unitary conspiracy but at most had participated in a number of smaller, unrelated conspiracies. The district court delivered the following instruction on the subject of multiple conspiracies: The indictment charges that the defendants participated in a single conspiracy to distribute illegal narcotics. Proof that there were multiple conspiracies is not necessarily proof of a single conspiracy, nor is it necessarily inconsistent with the existence of a single conspiracy. If you do not find beyond a reasonable doubt that a particular defendant was a member of any conspiracy, you should find that defendant not guilty of Count 1 [the conspiracy charge]. If you find beyond a reasonable doubt that there was one overall conspiracy as alleged in Count 1, and that a particular defendant was a member of that conspiracy, then you should find that defendant guilty of Count 1. If you find beyond a reasonable doubt that there were two or more conspiracies, and that a particular defendant was a member of or aided and abetted one or more conspiracies, you may find that defendant guilty of Count 1, if you further find beyond a reasonable doubt that this proven conspiracy was included within the conspiracy alleged in Count 1. If, on the other hand, the proven conspiracy is not included within the conspiracy alleged in Count 1, you should find the defendant not guilty of Count 1. Tr. 5332-33. The defendants argue that this instruction deprived them of their Fifth Amendment right to due process, and to their Sixth Amendment right to trial by jury, because although it required each juror to find that a defendant had participated either in the conspiracy alleged in the indictment or a lesser conspiracy included within the charged conspiracy, it did not state that the members of the jury must agree on which conspiracy the defendant had joined. As the defendants acknowledge, however, we approved a virtually identical instruction in United States v. Wilson, 134 F.3d 855, 865 (7th Cir.), cert. denied, 525 U.S. 894, 119 S.Ct. 216, 142 L.Ed.2d 178 (1998). We noted: [The instruction] informed the jury that, if it found that a defendant was a member of a conspiracy that constituted a sub-part of the conspiracy charged in the indictment, then it should find that defendant guilty. The jury’s finding of guilt therefore concluded that the [defendants] were members of a conspiracy and that, at a minimum, this conspiracy was part of the single conspiracy alleged by the Government. Id. at 865. That the jurors were not informed they must agree on exactly which conspiracy the defendant agreed to join does not present a constitutional problem. Even if the jurors were of different minds as to the precise parameters of the conspiracy, the instruction required them all to agree that the defendant joined a conspiracy that was within the ambit of the conspiracy alleged in the indictment. In short, with respect to the essential elements of the crime (the existence of a conspiracy, and the defendant’s agreement to join it), the instruction appropriately required unanimity. See Richardson v. United States, 526 U.S. 813, 817, 119 S.Ct. 1707, 1710, 143 L.Ed.2d 985 (1999). Moreover, even if the instruction were defective as the defendants suggest, the error was harmless. The evidence overwhelmingly demonstrated that the defendants participated in a unitary conspiracy to traffic in narcotics, pursuant to which Bahman and Mohammad Mansoori supplied the drugs to Young, who in turn, with the assistance of Cox and Choice, distributed them through a network of drug spots. F. Failure to Submit Drug Quantity to Jury The district court sentenced defendants Young, Mohammad Mansoori, Cox, and Choice to terms of life imprisonment based on its finding that they conspired to distribute more than 150 kilograms of cocaine. See, e.g., R. 745-3, Young Sentencing Tr. 35-37; R. 730, Cox Sentencing Tr. 21, 23-24; R. 748, Choice Sentencing Tr. 17-18. The various subsections of 21 U.S.C. § 841(b)(1) set forth a number of different minimum and maximum sentences depending on the amount of drugs involved, and subsection (A) specifies a maximum prison term of life for narcotics offenses involving five or more kilograms of cocaine or one or more kilograms of heroin. However, pursuant to the Supreme Court’s opinion in Apprendi v. New Jersey, 530 U.S. 466, 120 S.Ct. 2348, 147 L.Ed.2d 435 (2000), the indictment must allege, and a jury must unanimously find, that the offense involves that threshold amount before the court may sentence a defendant to the life term authorized by section 841(b)(1)(A). See, e.g., United States v. Smith, 241 F.3d 546, 547 (7th Cir.), cert. denied, — U.S.-, 122 S.Ct. 267, 151 L.Ed.2d 195 (2001). In the absence of a jury finding, the default statutory maximum for cases in which no particular quantity of narcotics is proven' — the twenty-year maximum provided for in section 841(b)(1)(C) — applies. In this case, the jury was not asked to decide whether the conspiracy involved any particular drug amount; on the contrary, the court instructed the jury that “[t]he Government does not have to prove the amount of controlled substances alleged in the indictment,” Tr. 5335, but rather it need only determine that the offenses charged in Count 1 (the conspiracy charge) and Count 2 (a substantive charge of distribution against defendants Young and Choice) involved “a measurable amount” of narcotics, id. Accordingly, the district court, which sentenced the defendants before the Supreme Court decided Apprendi, erred in imposing any sentence in excess of the default maximum of twenty years. As this issue was not raised below, however, the mistake must qualify as “plain” before the defendants are entitled to relief. United States v. Nance, 236 F.3d 820, 823-24 (7th Cir.2000), cert. denied, — U.S.-, 122 S.Ct. 79, 151 L.Ed.2d 43 (2001). Because we do not believe that the sentencing error affected the fairness, integrity, or public reputation of the proceedings below, see Johnson v. United States, 520 U.S. 461, 467, 117 S.Ct. 1544, 1549, 137 L.Ed.2d 718 (1997), we conclude that the error does not constitute “plain” error. Having reviewed the record, we are convinced that upon a properly worded indictment, a properly instructed jury would have found the defendants guilty of distributing the requisite threshold quantities of narcotics. See Nance, 236 F.3d at 825-26. The jury convicted the defendants on the conspiracy charge, and the record leaves no doubt that the conspiracy involved the distribution of far more than five kilograms of cocaine and/or one kilogram of heroin. Indeed, the trial evidence readily confirms the trial court’s finding that the defendants who received life terms were responsible for the distribution of at least 150 kilograms of cocaine. For example, co-conspirator Billy Carter testified that in 1994 he and Young had retrieved a twenty to thirty-kilogram quantity of cocaine from Mohammad Mansoori— whom Carter knew as “Moe” — which cocaine was then passed along in five or ten-kilogram quantities to other TVL members, including defendants Cox and Choice. Tr. 690-97. Carter said that he retrieved comparable quantities of cocaine from Mansoori more than five times in 1994 and 1995. Tr. 1052-53. Carter further testified that he alone was distributing three to five kilograms of cocaine per week in 1992, and five to ten kilograms weekly in 1993 and 1994 — which yields a total of several hundred kilograms. Tr. 1119-22. In a similar vein, Leslie Teague testified that he and co-conspirator Andre Donaldson obtained about five kilograms of cocaine per week from Young during the first few months of 1994 for distribution in the Quad Cities area of Illinois. Tr. 2090. (Carter testified that he and Choice delivered ten kilograms of cocaine to Teague on one occasion in 1993 or 1994. Tr. 696-99.) The evidence concerning heroin distribution similarly confirms that the conspirators were dealing in large quantities. TVL member Anthony Buchanan, for example, who shared a drug spot with Carter, testified that he obtained quantities of between 100 and 800 grams of heroin from Mohammad Mansoori and his “runner” John Hunt once or twice weekly in 1996. Tr. 1844-50. Carter testified that he was distributing 100 grams of heroin per day in that same year. Tr. 1117-18. Terry Bronson testified that Choice had him deliver 2.4-gram “packs” of heroin (twenty-four bags, each containing 0.1 gram of heroin) to the Henry Horner Homes on a daily basis from February to October 1996 (yielding a total of more than 500 grams). Tr. 342-43. Thus, the evidence before the jury consistently and overwhelmingly demonstrated that the defendants were distributing cocaine and heroin on a very large scale. In view of that evidence, there can be no doubt that the jury would have found that the offense involved the threshold amount of five kilograms of cocaine and/or one kilogram of heroin as necessary to authorize prison terms of life for defendants Young, Mohammad Mansoori, Cox, and Choice. See Nance, 236 F.3d at 826. G. Erroneous Life Sentences on Count Two Count Two of the superseding indictment charged Young and Choice (among others) with the distribution of one kilogram of cocaine in the October 31, 1996 transaction described at the outset of this opinion. R. 133 at 5. Pursuant to 21 U.S.C. § 841(b)(l)(B)(ii), the maximum prison term that could ever be imposed on this count was forty years because the underlying conduct involved more than 500 grams of cocaine but less than five kilograms. The district court, however, erroneously sentenced Young and Choice to life terms on this count. The government concedes the error. Gov. Br. 56 & n. 28. Accordingly, we shall remand the case to the district court for re-sentencing on this count. Because the jury was not asked to determine whether the defendants were responsible for distributing anything more than a “measurable amount” of cocaine, Tr. 5335, in accord with Apprendi the district court on remand may not impose a sentence in excess of twenty years on Count 2. See 21 U.S.C. § 841(b)(1)(C). It may well be true, as the Government contends, that the jury inevitably would have found Young and Choice responsible for distributing a kilogram of cocaine, thus triggering the forty-year maximum, had it only been asked to do so. That point would only be relevant, however, if we were deciding whether a forty-year term, imposed without the quantity finding that Apprendi requires, amounted to plain error. In this case, because the district court imposed a life term on Count 2 (a term that would be erroneous regardless of whether the jury had found the defendants named in this count responsible for a kilogram quantity of cocaine), re-sentencing is mandated. When it imposes the new sentence, the district court will of course be obliged to honor Apprendi. Because the jury did not render a quantity finding, as Apprendi requires, the maximum term that the district court may impose on remand is the default maximum term of twenty years specified in section 841(b)(1)(C). H. Erroneous Special Assessments The district court imposed special assessments of $100 as to Mohammad Man-soori on Counts 3 through 13 and Young on Count 14. Because these monetary offenses were committed prior to April 24, 1996 (see R. 133 at 6, 8), when the applicable special assessment was raised from $50 to $100, only a $50 special assessment could be imposed. E.g., United States v. Gricco, 277 F.3d 339, 363-64 (3rd Cir.2002); United States v. Prather, 205 F.3d 1265, 1272 (11th Cir.), cert. denied, 531 U.S. 879, 121 S.Ct. 188, 148 L.Ed.2d 130 (2000). Accordingly, we shall also remand for re-sentencing in this regard as well. I. Admissibility of Cox’s Post-Arrest Statement After a federal grand jury indicted Cox and hi