Opinion ID: 2803111
Heading Depth: 1
Heading Rank: 2

Heading: Ramos and Omar's Brady Claims

Text: At some unspecified time before the trial of this case, Delgado sent the lead prosecutor a handwritten letter that was, on its face, a document that the prosecutor was required to disclose to defense counsel prior to trial. The prosecutor did not make this disclosure. Instead, she recounts that she put a copy of the letter in her file for the separate trial on the witness tampering charges against Ramos, and forgot about it even as she tried this case in which Delgado was, in her words, her star witness. She then came across the letter after the trial of this case when preparing to try the witness tampering case. The prosecutor also managed not to provide defense counsel prior to the verdicts a 3 The jury also found all four appellants guilty of the forfeiture counts. -10- series of notes Delgado kept, or notes taken by FBI agents during their interviews with another indicted co-conspirator, Gabriel Medina-Pabon (Medina). The belated production of these materials set off a series of post-trial evidentiary hearings and motions by Ramos, Omar, and Sandra. The district court, in four separate opinions issued between 2010 and 2013, rejected the appellants' various arguments for a new trial based on the belated productions. Those four opinions provide a detailed account of each of the hearings conducted by and motions submitted to the district court. See United States v. Ramos-González, 747 F. Supp. 2d 280, 284—89 (D.P.R. 2010); United States v. Ramos-González, No. 07-318, 2011 WL 2144215, at —2 (D.P.R. May 31, 2011); Opinion & Order, ECF No. 2648 at 1—3, July 30, 2012; Opinion & Order, ECF No. 2972 at 1—6, August 9, 2013. We describe the details of the withheld evidence and the district court's reasoning.

The evidence of Delgado's letter to the prosecutor consisted of two photocopied pages of handwritten text. The certified translation of the letter states as follows: To: The Prosecutor Dina Avíla Jímenez From: The best cooperator, Harry S. Delgado Hello! I hope under God Almighty that when you receive the foregoing in your hands, you enjoy perfect health together with your co-workers -11- and relatives. It is my best wish from the bottom of my heart. About me, I tell you that [illegible], I am well health-wise. I will start by saying that this is to let you know to please remember these 2 things, the first is that Jeanette4 is on probation and before she leaves the country, to clarify that point of view, because otherwise, they'll deem her as a fugitive and they may take away my daughters, and that would kill me, please clarify this thing of the probation first; and the second thing, I need an order from the Judge so that when they transfer me Jeanette can visit me, remember that I am not legally married, and to get visits you have to fill in a paper that you have to put your home and the criminal record and it is not convenient for any jail to know where Jeanette lives, what we want is that the least they know, the better, please help me, I am doing everything for my daughters and Jeanette. I need you to help me please. I promised you, the last time we saw each other, to do everything you said and I have done it to the point that you know how this has gotten, we have more than we expected, more evidence and more strength for the case, I hope you can help me, I will The photocopy of the letter is cut off after I will at the end of the letter's second page. The prosecutor reports that when she re-discovered the letter after the trial, she asked the FBI agents to go through each . . . folder or envelope to see if they could find the original, but they were unable to find it. Ramos-González, 747 F. Supp. 2d at 286—87. The prosecutor said that the agents could not find any other materials related to the letter, and she denied destroying any part of the letter herself or 4 Jeanette was Delgado's conjugal partner. -12- instructing the agents to destroy part of the letter. The district court was unable to definitively determine whether additional pages were missing from the letter and, if so, how such pages may have disappeared. Id. at 284.
Delgado made notes of two conversations with Andy and Medina on the night of December 9, 2008, one at 8:57 p.m. and the other at 9:18 p.m. Id. at 287. Those conversations took place through the toilet system at MDC, id. at 287, where, as we mentioned above, Delgado, Xiomara, Andy, and Medina were all incarcerated leading up to the drug trafficking trial. The notes reflect that Andy and Medina attempted to curry favor with Delgado (who they presumably knew was the lead cooperator) and to downplay their own roles in the conspiracy. According to the notes, Medina said: Look [Delgado], I'm calling to tell you that I am cooperating in the case with the prosecutor and I know you are getting [Xiomara] ready. . . . Andy and I are going to cooperate, I already started to cooperate. Medina then questioned Delgado as to why the government was plac[ing] [him] at the [drug] point when you know that I wasn't working there. Andy also denied being an enforcer. Delgado replied: You very well know that you were dealing, and proceeded to remind Medina of a time when he assisted Delgado with storing guns. The rest of the -13- conversation basically reiterated Medina's pleas to Delgado to treat him well in prison. Delgado's notes also relate a later conversation between Delgado and Andy that had a similar tenor to Delgado's conversation with Medina. Andy asked why the government had him down as an enforce[r]. Delgado replied: Listen, you know that I know about your situation, and to tell you a little something, do you remember the meeting in Caguas, where you, [Ramos], Manolo, [Bam Bam], Eddie, Omar, and the others were there? Andy said: Yes, yes, yes, it's true, but I'm going to cooperate and I'm going to bring down all of those who stayed behind, and, What I want is that when we go up there, for us not to be enemies, but friends, and be only [one], so we can help each other. They then agreed to talk to each other again the following day at 8:00, but there are no notes of any subsequent conversations on the record. At some point the prosecutor, according to her testimony at a post-trial proceeding, scolded Delgado for making the notes after he turned them in and ordered him to stop making them.
FBI agents interviewed Medina three times in November and December 2008 about the drug conspiracy, but Medina never testified at trial. The prosecutor turned over the FBI 302 Reports (the FBI's official notes of what was said during the interviews) prior to trial, but she withheld rough notes transcribed by one of the -14- interviewers, FBI Special Agent Carlos Barreiro. The rough notes were finally disclosed to defense counsel in September 2012 at one of the post-trial evidentiary hearings involving allegations by Ramos and Omar that the government intimidated Medina, causing him not to testify on behalf of Ramos at an earlier post-trial hearing. These notes, including the Spanish version and English translation, span 121 pages of our appellate record. The rough notes' content largely overlaps with the information in the disclosed 302 Reports. However, Omar, whose motion for a new trial on the basis of these notes was joined by Ramos, argued before the district court that the rough notes contained various new pieces of exculpatory impeachment evidence. For example, the notes stated that Andy and another individual tapped Xiomara's [phone] line and listened to conversations between her and [Delgado] in prison. Medina also omitted any mention of Omar's involvement within the time period in the indictment (the only mention of Omar concerned events occurring in 1999), which Omar argued below and on appeal is totally exculpatory as to him. And Medina inferred that Delgado murdered a man known as Barquilla, even though Delgado denied having anything to do with that murder while on the stand.
In a series of four detailed opinions, the district court rejected all arguments that the above-described evidence was -15- sufficiently impeaching or exculpatory to warrant a new trial. The court concluded that, had the defense possessed the evidence prior to trial, none of it would have had a reasonable probability of changing the result.5 In the first opinion, the court made a preliminary finding that the evidentiary hearing allowed the Court to gauge [the prosecutor's] testimony as credible and supportive of her avowal of good faith in belatedly disclosing the evidence by reason of inadvertence. Ramos-González, 747 F. Supp. 2d at 287. As for the evidence's materiality, the court found that: The evidence . . . [was] principally aimed at impeaching Delgado's credibility and bias in favor of the government, issues that were already opened at trial and closed shut by the jury. . . . Beyond the smokescreen of factual allegations attacking Delgado's credibility, which were in large part previously decided by the jury, Defendants have not pointed to a single piece of material evidence that undermines the guilty verdicts, especially when substantial evidence corroborates their participation in the drug trafficking conspiracy. Id. at 292. With regard to Delgado's letter, the district court pointed out that the defendants had in their possession, before trial, information showing Delgado's receipt of benefits from the government, including assistance with relocating his family. Id. at 293. Moreover, Delgado admitted on direct examination that his 5 We discuss the applicable legal standard in greater detail in Part 1.C, below. -16- family received close to $10,000 from the FBI for his cooperation, and the court warned the jurors that Delgado's receipt of such benefits could affect his veracity and should be considered in judging his credibility. Id. Therefore, the district court concluded that the letter, stripped to [its] bare essentials, . . . say[s] nothing more than what has already been said about Delgado at trial and the attempt to impeach Delgado with the letter could only be described as cumulative. Id. at 294. Similarly, the court found that Delgado's conversations with Andy and Medina as reflected in Delgado's notes fell into the same general category of cumulative or collateral impeachment evidence failing to create a reasonable probability of acquittal. Id. at 294. The court explained that the notes simply reflect conversations by two co-defendants who were either contemplating cooperating or already decided upon cooperating with the Government. In essence, [Andy] and Medina [were] attempting to exculpate themselves, not Defendants, from playing major roles in the drug conspiracy, and are attempting to curry favor with Delgado . . . such that he would treat them fairly when they would arrive and reside together at the cooperator's [sic] unit. Id. at 295. The court fail[ed] to see how the conversations [between the cooperators] were clearly related to the drug trafficking charges in the sense that the cooperators were discussing any key material factual allegations relating to [the appellants'] participation in -17- the conspiracy and guilt. Id. at 296. Thus, this evidence, too, was collateral because [it did] not exculpate Defendants in any way, and, [it was] cumulative because the fact that the cooperators spoke in prison . . . was subject to extensive cross-examination at trial. Id. With respect to the rough notes (which were not produced until 2012, two years after the court issued its first post-trial opinion), the court again concluded the evidence was both collateral and cumulative. As a general matter, Medina's testimony at a 2012 hearing for the government's alleged prosecutorial misconduct, while still inculpating the defendants, conflicted with many of the statements reflected in the rough notes. Thus, the probative force of his pre-trial statements was weak, and the notes of those interviews did little, if nothing at all, to undermine the confidence of the verdict against the defendant. In response to Omar's claim that the absence of any mention of his involvement in the rough notes during the period included in the indictment was totally exculpatory to him, the court concluded that such an absence was at best neutral and therefore immaterial. Finding that the undisclosed evidence was neither new or [sic] exculpatory, but was collateral and cumulative, and that -18- the government did not engage in any misconduct, the court denied the defendants' final motion for a new trial.6
On appeal, only Ramos and Omar renew their contentions that the withheld evidence warranted a new trial, so we evaluate the Brady issue solely with respect to them.7 The appellants brought their new trial motions under Federal Rule of Criminal Procedure 33, which provides that [u]pon the defendant's motion, the court may vacate any judgment and grant a new trial if the interest of justice so requires. We review the district court's denial of a Rule 33 motion for manifest abuse of discretion. González-González, 258 F.3d at 20. As this circuit has previously explained, motions for a new trial based on newly discovered evidence generally require a 6 The court's denial of the defendants' motion to dismiss the indictment due to the government's alleged prosecutorial misconduct is not at issue in this appeal. 7 Sandra's trial counsel joined Ramos and Omar in petitioning the district court for a new trial after the prosecutor turned over Delgado's letter and notes in 2010. Her appellate counsel has not renewed this claim on appeal. Counsel was clearly aware of his ability to adopt a co-appellant's arguments in a consolidated case pursuant to Federal Rule Appellate Procedure 28(i), since he reserved his right to do so in Sandra's opening brief. But counsel never filed a reply brief after the court granted him an extension, nor did he make a motion to adopt the other appellants' arguments. Sonia did not make a motion for a new trial below and does not attempt to piggyback on her co-appellants' motions on appeal, even though her appellate counsel was clearly aware of the Brady issue, since she is also representing Ramos in this appeal. Sonia's opening brief includes a footnote referencing Delgado's letter but makes no argument in relation to it. -19- four-pronged showing that: (1) the evidence was unknown or unavailable to the defendant at the time of trial; (2) failure to learn of the evidence was not due to lack of diligence by the defendant; (3) the evidence is material, and not merely cumulative or impeaching; and (4) it will probably result in an acquittal upon retrial of the defendant. Id. (quoting United States v. Wright, 625 F.2d 1017, 1019 (1st Cir. 1980)). However, when the basis for the motion is that the government failed to disclose evidence required to be disclosed under Brady, either willfully or inadvertently, we apply the more defendant-friendly Kyles v. Whitley standard to the test's third and fourth prongs. See Kyles v. Whitley, 514 U.S. 419, 434 (1995); United States v. Josleyn, 206 F.3d 144, 151—52 (1st Cir. 2000). Instead of requiring that the defendant show that an acquittal would have probably resulted had the material been produced, we require only that the defendant show a reasonable probability that had the government disclosed the evidence prior to trial, the result of the proceeding would have been different. González-González, 258 F.3d at 20. Answering that question requires that we determine whether a trial held in the absence of such evidence can be described as a trial that can produce a verdict worthy of confidence. Id. (citing Kyles, 514 U.S. at 434). This somewhat delphic 'undermine confidence' formula suggests that reversal might be warranted in some cases even if there is less than an even chance that the evidence would -20- produce an acquittal. Conley v. United States, 415 F.3d 183, 188 (1st Cir. 2005) (internal quotation marks omitted).
We pause here to acknowledge that this is not the first time our circuit has referenced the district court's 2010 opinion rejecting Ramos and Omar's request for a new trial based on Delgado's letter and toilet conversation notes.8 In United States v. Ramos-González, 775 F.3d 483, 509—10 (1st Cir. 2014) (which we will call the possession case for purposes of this discussion), we affirmed Ramos's conviction for a separate drug offense.9 One of Ramos's arguments in his appeal from the possession case conviction was that the indictment against him should have been dismissed, in part because the prosecutor also failed to timely disclose certain 302 Reports of interviews with Ramos's arresting officers. Id. at 491–92. To buttress his claim of prosecutorial misconduct in that case, Ramos pointed out that the prosecutor in that case was the same one who also failed to timely disclose the above-described letter and notes from Delgado in the instant conspiracy case. Id. at 492. Ramos urged us to find that the 8 Because the prosecutor did not disclose the rough notes until 2012, they were not addressed by the district court until 2013. 9 We also remanded the possession case for resentencing in light of the district court's erroneous application of the career offender enhancement under the sentencing guidelines. Id. at 487, 503–08. -21- prosecutor's actions, considered cumulatively in the two cases, amounted to a recurrent pattern of concealment and deception and a flagrant disregard for [his] constitutional rights that warranted a dismissal of the indictment in the possession case. Id. We rejected that argument. After explaining why the prosecutor's failure to disclose the 302 Reports in the possession case itself did not constitute an extreme case of prosecutorial misconduct, id. at 493, we addressed Ramos's argument based on the cumulative conduct in the two cases. In so doing, we express[ed] concern about the repeated nondisclosure of evidence in the prosecutions against Ramos and noted that [t]he United States Attorney's Office should develop procedures to avoid repeating the lapses that occurred in these cases. Id. at 494. Nevertheless, we affirmed the verdict in the possession case and made the following statement regarding the ruling in this case that is now the subject of this direct appeal: As an initial matter, the district court in the conspiracy case took the defendants' Brady claims seriously, conducted an evidentiary hearing, and wrote a thoughtful opinion explaining why the alleged violations there did not warrant a new trial. Given such careful treatment, that court's judgment that no constitutional violation occurred in the trial over which it presided is owed deference by both the district court in the instant case and by us on appeal. Id. at 493–94 (internal citation omitted). -22- So we must first ask whether the above-quoted language dictates the resolution of the Brady issue on this direct appeal. For the following reasons, we think not. First, the precise question posed in the possession case trained on the conduct and good faith of the prosecutor. The argument posed was that misconduct in one case supported a finding of misconduct in another, or that two errors could not be explained as innocent. To reject that argument, it was sufficient to defer to the district court's finding that the prosecutor did not act in bad faith. As we will explain, there is no need to revisit that finding on this appeal. Second, and relatedly, in its collateral discussion of the district court ruling in the instant case, the prior panel (which included one of the judges on this panel) simply did not have the complete record. This appeal in this case is the first appellate opportunity to examine the above-described Brady material and to analyze its potential effect on the appellants' drug conspiracy convictions. We re-emphasize, and this is critical, that the dispositive inquiry in determining whether a defendant is entitled to a new trial under Brady is whether there is a reasonable probability that the newly discovered evidence would result in an acquittal in this case. Since we have never before looked at the full record to determine whether Delgado's letter and notes would have any effect on the jury's finding in the instant -23- conspiracy case, our deferential statement that the district court's 2010 opinion was careful and thoughtful contains limited, if any, value to us in deciding Ramos and Omar's claims. We proceed with our analysis.
The district court did indeed recite with care and thought the correct standards and, as we have summarized above, it issued detailed opinions rejecting the appellants' arguments. Nevertheless, we disagree with the district court's ultimate conclusion that the withheld evidence, considered cumulatively, lacked sufficient materiality to create a reasonable probability of acquittal had it been disclosed. Our disagreement is strong enough to overcome the considerable deference we must yield to a trial court on such decisions. We begin with the well-established principle that, under Brady, the government has an affirmative duty to disclose evidence favorable to a defendant, be it exculpatory or impeachment evidence. Kyles, 514 U.S. at 432—33. However, [w]e do not . . . automatically require a new trial whenever a combing of the prosecutors' files after the trial has disclosed evidence possibly useful to the defense but not likely to have changed the verdict. United States v. Dumas, 207 F.3d 11, 15 (1st Cir. 2000) (quoting Giglio v. United States, 405 U.S. 150, 154 (1972) (internal quotation marks omitted)). The following guidance on materiality -24- compiled from Supreme Court and First Circuit precedent is particularly instructive with respect to the newly discovered evidence in this case: In analyzing whether there was a Brady violation, we evaluate the strength of the impeachment evidence and the effect of its suppression in the context of the entire record to determine its materiality. The import of withholding evidence is heightened where the evidence is highly impeaching or when the witness' testimony is uncorroborated and essential to the conviction. . . . We must grant a new trial if, after assessing the significance of the non-disclosed evidence in the context of trial, the favorable evidence could reasonably be taken to put the whole case in such a different light as to undermine confidence in the verdict. Avilés-Colón, 536 F.3d at 19 (internal quotation marks and citations omitted) (quoting, inter alia, Strickler v. Green, 527 U.S. 263, 290 (1999) and Kyles, 514 U.S. at 435). Applying this test, we observe, first, that the testimony of the three cooperating witnesses--especially Delgado--was both essential to the convictions and uncorroborated by any significant independent evidence. Indeed, the absence of such evidence is so marked and surprising in view of the resources devoted to the investigation and the availability of three turned conspirators that it could reasonably cause the factfinder to be dubious about the witnesses' claims. This is therefore a case in which the Brady material that was not produced need not be highly impeaching in -25- order to require that the verdict be reversed. Avilés-Colón, 536
Delgado was the star witness. The prosecutor told us so much at oral argument and emphasized Delgado's testimony throughout her closing argument at trial. His direct examination lasted an entire day, and his cross, re-cross, and re-direct examination lasted a day and a half more. On cross, defense counsel worked through the usual litany of attacks one might make on any cooperating witness. Delgado parried any suggestions that his testimony was orchestrated with that of the other witnesses. In fact, he denied even talking about the case with them, telling the jury that to do so was against the rules. So, too, did those other two cooperating witnesses firmly deny a basic premise of the defense: that they coordinated their testimony. Had defense counsel possessed Delgado's notes, counsel could have either shown Delgado and the others to have perjured themselves, and/or forced them to admit that they had at the very least compared prospective testimony with one another. The notes indicate that Delgado was encouraging Andy and Xiomara to testify, and recount in detail at least one conversation where Delgado reminded Andy about a meeting involving Ramos and Omar, which a jury could have interpreted as Delgado telling Andy what to say. Similarly, the rough notes show that Andy knew that Delgado and Xiomara were talking through the pipes. It was not just the -26- defense who believed the potential for the cooperators to talk about the case in prison jeopardized the government's chances of a conviction.10 The prosecutor elicited testimony from Andy on redirect that suggested male and female prisoners could not talk to each other at the prison.11 Delgado's letter to the prosecutor is probative for a different reason. Although it contains no fact directly at variance with his testimony,12 its overall tone turns it into what could clearly have been a focus of a defendant's closing. In the 10 In line with Supreme Court precedent, we decide whether the newly discovered evidence is material . . . to guilt . . . irrespective of the good faith or bad faith of the prosecution. Brady, 373 U.S. at 87; see also Kyles, 514 U.S. at 432. 11 We refer to the following exchange: Prosecutor: [Defense counsel] asked you whether you and Harry had discussed the facts of this case or the case about your testimony. Andy: Yes, he asked me that question. Prosecutor: Sir, what kind of gender inmates are in Four Charlie? Andy: We are all males. Prosecutor: So where is Xiomara located? Andy: The 3 C unit. Prosecutor: So you and Harry do not share a same unit with Xiomara? Andy: No. 12 The letter did contain at least one new fact that the defendants lacked at trial but that they could have used for impeachment purposes: Delgado's girlfriend Jeanette, who he references in the letter, was on probation while Delgado was cooperating. Delgado's letter suggests that the government was allowing Jeanette to travel out of Puerto Rico with Delgado's children due to his cooperation. -27- letter, Delgado presents himself as the prosecutor's best cooperator; a fawning, desperate supplicant willing to do everything [the prosecutor] said and eager to point out how much assistance he was providing her. Importantly, the fact that the last part of the letter appears to have been destroyed--the part where it seems he was saying what he would do--heightens greatly its probative value, both raising an inference of spoliation, see United States v. Laurent, 607 F.3d 895, 902 (1st Cir. 2010),13 and providing a powerful tool in the hands of any good trial counsel to call into question the credibility of both the key witness and, implicitly, the lead prosecutor.14 13 Omar argued below and on appeal that the prosecution's failure to preserve the entire letter supported a new trial under Arizona v. Youngblood, 488 U.S. 51, 58 (1988) (holding that bad faith destruction of evidence constitutes a due process violation). In Dumas, 207 F.3d at 15, we explained that in order to obtain a new trial on a Youngblood-style destruction of evidence rationale, [t]he defendant must show that, in failing to preserve the evidence, the government, (1) acted in bad faith when it destroyed evidence, which (2) possessed an apparent exculpatory value and which (3) is to some extent irreplaceable. While the district court's finding of no bad faith prevented a new trial based on the destruction of evidence rationale alone, the appellants likely would have been entitled to a spoliation instruction, allowing the jury to make an adverse inference that the destroyed evidence was favorable to the defense. See Laurent, 607 F.3d at 902. Thus, the fact that the letter was partially destroyed is of import to our view of the withheld evidence's cumulative effect. 14 In noting that the apparently incomplete copy of the letter might suggest such an inference, we do not question the district court's conclusion that the non-production was unintentional. We do, however, repeat our concern that this United States Attorney's office, especially given its very heavy workload, appears to need better procedures for gathering and producing Brady materials. See Ramos-González, 775 F.3d at 494. -28- In deeming all this evidence to be merely cumulative, the district court twice erred. First, the district court relied heavily--at least twice--on its observation that the jury believed Delgado based on the evidence it did hear. But this begs the question of whether the jury would have believed Delgado if it had also heard the omitted impeachment evidence. Second, the fact that the defense had some tools to attack Delgado's testimony hardly dismisses the potential of different tools as merely cumulative. If defense counsel had firm proof that a witness received $500 from the government, a letter confirming such a payment would be cumulative. But a letter revealing another payment of $50,000 would be cumulative only in the sense that its relevance pointed toward the same conclusion. This type of cumulative evidence can be quite probative. Here, moreover, there was no other document or recording tending to prove that the witnesses were lying when they denied discussing their testimony with one another. In so concluding, we have considered the district court's finding that Ramos' camp was aware of conversations among co-defendants through the toilet at MDC prior to trial. The district court based this finding upon Medina's post-trial testimony recalling a pre-trial meeting with Ramos's investigator in which he told the investigator that he heard Delgado and Xiomara discussing the case through the toilets. The investigator also testified and denied such a meeting ever -29- occurred, but the district court (despite finding Medina not to be a credible witness) nevertheless concluded that the toilet conversations were not unavailable to Ramos under the first prong of Brady, and thus, the motion for new trial must be denied[.] See United States v. Del-Valle, 566 F.3d 31, 38 (1st Cir. 2009) (to establish a Brady violation, evidence must be unknown or unavailable to the defendant at the time of trial). We disagree with the district court's analysis. First, a fact known to counsel remains entirely unknown to a jury unless counsel has admissible evidence of the fact. There is no evidence that Medina would have been willing to testify at Ramos's trial or that he could have been so compelled. Second, even if Medina had testified at trial, a swearing contest between Medina and Delgado is hardly the same in terms of impeachment value as notes written in Delgado's own hand. See United States v. Paladin, 748 F.3d 438, 446 (1st Cir. 2014) ([S]uppressed impeachment evidence can be immaterial because of its cumulative nature only if the witness was already . . . impeached at trial by the same kind of evidence. (internal quotation marks omitted)). And in this latter respect, it is noteworthy that in concluding that Medina's testimony lacked a reasonable probability of changing the result at trial, the district court opined that Medina was not a credible witness considering the numerous inconsistencies in [his] statements. We also reiterate that our holding is based on the cumulative impact -30- of all of the newly discovered evidence, not solely the content of Delgado's alleged conversation with Xiomara. See Kyles, 514 U.S. at 420 (explaining that the disclosure obligation turns on the cumulative effect of all suppressed evidence favorable to the defense, not on the evidence considered item by item). We also recognize that, in some sense, the letter and notes were collateral because they did not directly bear on the factual evidence underlying the government's case. See id. at 448; United States v. Beauchamp, 986 F.2d 1, 4 (1st Cir. 1993) (A matter is considered collateral if 'the matter itself is not relevant in the litigation to establish a fact of consequence, i.e., not relevant for a purpose other than mere contradiction of the in-court testimony of the witness.' (quoting 1 McCormack on Evidence § 45, at 169 (4th ed. 1992))). Yet in another, very important sense, the evidence is anything but collateral because the possibility that the three linchpin witnesses colluded to fabricate incriminating testimony goes to the very core of this case and potentially compromises every piece of factual evidence the government had against Ramos and Omar. Semantics aside, here is where the rubber meets the road: This was a case that surprisingly pivoted entirely on the credibility of Delgado and his two cohorts. The unproduced Brady materials were the only evidence that would have eliminated the claim that the testimony was entirely uncoordinated, and the -31- Delgado letter would have provided a uniquely colorful tool for both attacking Delgado's motivation and raising the prospect that Delgado and the prosecutor were hiding something from the jury. Many members of the public would pause when told that a jury accepted Delgado's testimony--and convicted Ramos and Omar--without being shown any of these documents. See Norton v. Spencer, 351 F.3d 1, 9 (1st Cir. 2003) (Confidence in the outcome is particularly doubtful when the withheld evidence impeaches a witness whose testimony is uncorroborated and essential to the conviction. (internal quotation marks omitted)).15 We cannot say for sure what Delgado, Xiomara, and Andy would have said had they been confronted with this evidence on the stand (regardless of whether it was introduced on direct or cross-examination). Nor can we say that introduction of the withheld evidence would more likely than not have changed the verdict. But the grasp of our own conviction need not reach so far. Rather, under the applicable standard we need only find it to be reasonably probable that the 15 The lack of corroboration of the cooperators' testimony is a critical factor in helping us distinguish this appeal from other cases applying the same legal standard that came out the other way. See, e.g., Paladin, 748 F.3d at 493 (evidence of defendant's guilt was overwhelming and did not depend on [the informant's] credibility); United States v. Mathur, 624 F.3d 498, 505 (1st Cir. 2010) (multiple witnesses gave first-hand accounts of being victimized by the defendant, and government introduced physical evidence corroborating defendant's guilt); González-González, 258 F.3d at 18—19 (numerous other witnesses, who were not impeached by the newly discovered evidence, corroborated the impeached witness's testimony, and the government introduced voluminous incriminating documentary evidence of the defendant's guilt). -32- impeachment evidence would have caused the jury to acquit Ramos and Omar. See United States v. Prochilo, 629 F.3d 264, 268 (1st Cir. 2011). These circumstances satisfy that test due to the combined impact of Delgado's solicitous and suspiciously incomplete letter, the toilet conversation notes that the prosecutor scolded Delgado for making, and the FBI's rough notes. We therefore instruct the district court to grant Ramos and Omar's motions for a new trial. This finding disposes of Omar's appeal, since any potentially reversible mistakes arising from the other trial and sentencing errors he alleges will be--at least temporarily--cured by our grant of a new trial. Ramos, however, also makes a sufficiency of the evidence argument with respect to the aiding and abetting counts (counts three through six). A successful sufficiency claim would oblige us to direct the court to dismiss those counts of the indictment, see Burks v. United States, 437 U.S. 1, 10—11 (1978)--a more severe remedy than a new trial--so we still must analyze that claim despite our ruling on the Brady issue. As for Sonia and Sandra, neither of them pressed Brady claims before this Court. We therefore proceed to address Ramos's sufficiency claim and each of Sonia and Sandra's assignments of error below.