(dissenting).
With all due respect to my esteemed colleagues in the majority, I must dissent. I do so reluctantly because although I disagree with their characterization of the strength of the evidence against Moreno, see ante at 948-49, I agree that in all probability the jury verdict would have been the same sans the breaches committed during the trial. My reticence, however, is not sufficient to overcome my perturbation at what I perceive to be the virtual condonation, with nary but mild admonitions on our part, of repeated prosecutorial transgressions, almost to the point of a pattern. See, e.g., United States v. Agudelo, 988 F.2d 285 (1st Cir.1993) (admission of improper testimony); United States v. *950Williams, 985 F.2d 634 (1st Cir.1993) (admission of improper evidence); United States v. Smith, 982 F.2d 681 (1st Cir.1993) (improper argument by prosecutor); United States v. Hodge-Balwing, 952 F.2d 607, 611 (1st Cir.1991) (improper argument by prosecutor). The majority itself points out similar cases falling within this pattern, but fails to appreciate the extent of its perniciousness. See ante at 949 (citing Ma-chor, supra, and Giry, supra, as examples of “fierce” arguments by prosecutors). Compounding this problem is the fact that Rule 404(b) and the harmless error doctrine have been converted, not to say subverted, into a wall behind which the Government apparently can continue ad infinitum to take pot shots with impunity.
I register my protest because our past cautions, timid as they were, see, e.g., Agudelo, 988 F.2d at 288 n. 7, (“this is not to forget our complaint ... about giving the government two bites at the apple: push for evidence believed to be damning, and then say it was meaningless”); Williams, 985 F.2d at 638 (“to infect and jeopardize a prosecution with such evidence is unwise and unjustifiable”), have not only been ignored, but alas, have probably encouraged this continued conduct. I fear that the current warning, ante at 949, although somewhat more forceful than those that have come before, is likely to further erode our institutional credibility, if the past is any indication of the future. More importantly, I believe that the prosecutor's actions in the present case unconstitutionally prejudiced Moreno’s right to a fair trial.
To set the trial in proper perspective, a review of the facts is appropriate. Three unidentified persons were seen running from the sound of gunfire; at some point thereafter one of these persons appeared to pass a one to one-and-one-half foot long dark object to another person who kept on running with the unknown object; the passer then stopped running, was arrested (we know not for what crime at this point), and eventually was identified as Moreno; a person later identified as Frederick Hardy, the receiver of the unknown object, was intercepted and arrested coming from where Moreno was detained; Hardy was seen throwing away an object, which was later recovered and which turned out to be a .32 caliber pistol; no other weapon was found on or near Hardy, but a search of his suspected route revealed a loaded, double barrel, sawed off shotgun, hidden in the bushes along the direct path from where Moreno was arrested; this shotgun and its ammunition are the weapons with which Moreno is charged with illegally possessing.
At trial, the prosecutor introduced as Rule 404(b) evidence against Moreno a third weapon found elsewhere in the possession of a third individual, Stephen Fer-nándes. This weapon was a 9 mm. caliber pistol, as well as 10 casings fired from that weapon at the scene of the original shooting.
The prosecutor also made improper statements, which fall into three groups, at different points. First, he linked appellant to the rampant violence in the community, insisting at opening argument that “the evidence will show that [the police] were doing their jobs protecting the community that has been plagued by violence, senseless violence, shootings and killings.” He continued “[t]hat’s why they were there and that’s why we’re here today.” The prosecutor referred to the officers as members of an anti-gang unit on four occasions, and instructed the jury not to “reward” the defendants for discarding weapons. The prosecutor injected violence at every opportunity, stating, for example, that “[i]f you’re walking down the street with a baseball bat, it’s not illegal to possess it. If you use the baseball bat to bash in somebody’s head, that’s illegal,” and that “Mr. Hooker or his wife or his three kids might come out and look at the gun and get their heads blown off.” In describing the shotgun, which had not been fired, the prosecutor argued “[sjomebody had to move that lever, crack open that barrel and put those two shotgun shells into the shotgun. Somebody does that for a reason. Just remember that these three people armed themselves with three guns.” The prosecutor proceeded “[a]ll you had to do was pull the trigger. Think about going *951into the middle of that housing development armed with those weapons together and firing one of these weapons.”
Second, the prosecutor improperly vouched for the government witnesses, intimating that they possessed some information beyond the evidence presented. In discussing the “cylindrical object” that appellant passed on to another individual, the prosecutor warranted that the police “knew what it was, but they’re not overstating their testimony.” He later asserted “[t]hey knew what the object was. They were going to find it.”
Third, the prosecutor urged the jury to disregard appellant’s counsel because defense attorneys “are paid to see see [sic] things in a different way.” Furthermore, the prosecutor contended at one point that defense counsel was “talking out of both sides of his mouth.” The prosecutor, discussing a defense argument, explained “I’m not quite sure what that meant, but I would suggest that a part of it was designed to divert your attention.”
As the majority points out, the prosecution’s statement appealing to the jury’s fear of neighborhood violence was “patently improper” and “outside the bounds of legitimate argument and cannot be condoned.” Id. at pp. 947-48. “[N]o less disturbing,” finds the majority, is that “even after [being warned] the prosecutor again departed from the straight and narrow in his closing.” Id. at 948. This would have been sufficient basis for “reversal as a deterrent,” the majority tells us, only if “this second foray [had been] deliberate.” Id. This observation is irrelevant if the prosecutor’s statements caused harm to defendant, and harm undoubtedly was caused by these and other statements.
My colleagues place too much faith on the practical value of the curative instructions given by the trial judge, the second of which was admittedly “rather oblique” as to the matter objected.4 Id. at 948; see also United States v. Akinola, 985 F.2d 1105 (1st Cir.1993) (“it is the combination of the trial judge’s instructions ... that would render the prosecutor’s putative violation harmless”). Empirical studies have established that juries tend to consider relevant evidence in a case even when it is ordered stricken from the record. See Reid Hastie, Steven D. Penrod and Nancy Pennington, Inside the Jury 87, 231 (1983). In fact, juries are even more likely to consider such evidence if admonished by the court not to consider it, than if no specific instruction is given. See Saul Kassin and Lawrence Wrightsman, The American Jury On Trial: Psychological Perspectives 108-09 (1988). Even more troublesome to a criminal defendant in Moreno’s position are the studies indicating that juries tend to forget the source of the information they remember, and are often unable to recall whether the source of information came from a witness, or from one of the attorneys during the opening statement or closing argument. Id. at 106. These studies also show that juries treat statements made by counsel in opening statements as fact even though no evidence is later introduced to support the attorney’s assertion. Id. Harmful impact may also result from improper remarks in an opening statement, caused by a psychological phenomenon known as the “primacy effect,” which is a tendency to make snap judgments based on information presented early in the trial. Id. at 134. Once jurors form a first impression, they often discount or reject facts that challenge their views, and instead fill their trial memories in ways that favor their initial reaction. Id. at 134-35; see also N. Anderson, Foundations of Information Integration Theory 179-81 (1981).
Our cases repeatedly have ignored the practical effect of improper argument and evidence on the jury by excusing such impropriety as harmless error and then chiding the prosecutor. See, e.g., Agudelo, supra; Williams, supra; Hodge-Balwing, 952 F.2d at 611 (“we review only ‘blockbus*952ters: those errors so shocking that they seriously affect the fundamental fairness and basic integrity of the proceedings conducted below’ ”). The studies discussed above clearly demonstrate a common sense conclusion with empirical data: the prejudicial influence of such argument and evidence should not be easily disregarded in the manner we have done, as it flows more deeply than we have assumed.5 The studies lead to one inescapable conclusion in regard to this case: there is no way of knowing if the stricken remarks were in fact not influential in prejudicing the jury in a powerful and lasting way, and thus tipping the balance against him.
To this prejudice we add the impact on the jury of the so-called 404(b) evidence. This evidence proffered under the aegis of this rule consisted of: (1) testimony that pistol shots fired by unknown persons were heard by police officers prior to Moreno’s arrest; (2) a 9 mm. caliber pistol that was found on the ground near another individual; and (3) ten spent shell casings matching that pistol, which were found near area from which Moreno and three other men were seen running from after the shots were heard. As noted, supra at 949, the 9 mm. pistol was found in possession of a third person, Stephen Fernandes, who was not even tried together with appellant. All this evidence was allowed as probative in establishing “other crimes, wrongs or acts,” by Moreno, with regard to charges that he illegally possessed a loaded sawed-off shotgun. This is claimed to be evidence unrelated to Moreno’s character or propensity to commit crime and thus admissible for nebulous “other purposes.” Fed.R.Evid. 404(b).
This is clearly improper use of Rule 404(b). The evidence was not even proof of wrongful acts by Moreno, but, at best, evidence of other wrongful acts by third persons in Moreno’s presence. Because Rule 404(b) should only be invoked when prosecutors seek to introduce evidence of prior bad acts committed by the defendant, it is error to analyze this evidence under that rule. United States v. Moccia, 681 F.2d 61, 63 (1st Cir.1982) (Breyer, C.J.) (Rule 404(b) forbids prosecution from “asking the jury to infer from the fact that the defendant has committed a bad act in the past, that he has a bad character and therefore is more likely to have committed the bad act now charged”) (emphasis added). The proper inquiry is whether the evidence is relevant, and whether it is more prejudicial than probative. The correct answer to the first question is no, and the answer to the second is yes.
At best the evidence shows mere presence during the commission of other crimes by other persons. It asks the jury to conclude that appellant somehow was guilty of that crime, and by extension, guilty of the current crime. Appellant’s mere presence at the scene of that crime, of course, does not establish appellant’s guilt of that crime. See United States v. Aponte-Suárez, 905 F.2d 483, 491 (1st Cir.) (mere presence at the scene of a crime and knowledge that a crime was to be committed is not proof of guilt), cert. denied, 498 U.S. 990, 111 S.Ct. 531, 112 L.Ed.2d 541 (1990); see also Nye & Nissen v. United States, 336 U.S. 613, 619, 69 S.Ct. 766, 770, 93 L.Ed. 919 (1949). Furthermore, and with all due respect, concluding that persons present at the scene of a shooting, and thereafter fleeing, are more likely to be carrying weapons is highly illogical. It is just as likely that persons fleeing the scene of a shooting will be either unarmed victims or by-standers, and in fact, it is more probable that they would have more of an incentive to flee, and faster, precisely because they were unarmed. Thus, the inference that it is more likely that appellant is guilty of the felon-in-possession crime because he was fleeing from the scene of *953another crime committed by other persons is insupportable. The evidence is constitutionally and factually irrelevant.
Even if the evidence was relevant, its probative value pales in comparison to its prejudicial effect. Any probative value that the evidence may have stems from extended inferences and speculation about the probabilities of people carrying weapons. Inferences and speculation, however, are infected too easily in this case by the transference of guilt from the shooting of a gun by a third party to the charged crime of possession, ensuring that a jury will draw all doubt against appellant. See United States v. St. Michael’s Credit Union, 880 F.2d 579, 602 (1st Cir.1989) (danger that jury might convict defendant on theory of guilt by association). When added to the impact of the prosecutor’s improper argument concerning senseless killings and community violence, the prejudicial impact becomes manifest. The majority opinion chooses to ignore the prejudicial effect of this evidence, concluding that the defense somehow waived any consideration of the issue.
Lastly, let us return to the trial itself, and consider the overall impact of these breaches. I have already conceded that even without the Rule 404(b) evidence, appellant probably would not withstand a Rule 29 motion. The evidence concerning the cylindrical object and the shotgun is perfectly valid, and one can conclude that the charged possession of a shotgun in fact occurred from it. The conclusion can only be reached through extended inferences, though, because no witness testified that they actually saw Moreno with the weapon, but only that he passed something to someone who was later found nearby the weapon. Given the prejudice already infused into the trial by the improper argument and evidence, I do not see how it can be discounted that the required inferences supporting this conclusion were not themselves infected. In all likelihood this prejudice would make the jury more predisposed to draw the required inferences against appellant, thus tipping the balance against him.
What we have here is a vulnerable case requiring the jury to make substantial inferences in order to convict. The prosecution beefed up its case by clearly improper statements at crucial stages of the trial, and threw in pseudo 404(b) evidence for good measure. Although the defendant did not create this situation, he is asked to assume all the risks it generates. Somehow this is not my idea of a fair trial. It contradicts all logic and practical experience. It is past due that this court send a clear message regarding the standards that are expected of a litigator whose motto is that “[t]he United States wins its point whenever justice is done its citizens in the courts.” It is better that this message be given in this case than in a case of more societal consequence.
This appellant did not get a just trial. A new one should be ordered.
. The majority indicates that they “are satisfied that the jury got the message to ignore what had just been said." Id. at 948. I would ask rhetorically what there is in the instruction to cause such reassurance. Certainly nothing in its obliqueness, and I would think, little in its length would commend such a conclusion.
. Thus, the “powerful and contemporaneous instruction” referred to by the majority, ante at 948, was indeed such, but not as intended. It served to remind the jury "about other violence” and senseless killings. Id.
Indeed, these studies starkly reveal the dilemma that attorney's face in this area of the law. They must choose either to ask for a curative instruction, increasing the impact of the improper argument or evidence, or remain silent, in which case they waive the issue on appeal, see United States v. Tejeda, 974 F.2d 210, 215 (1st Cir.1992).