Opinion ID: 781605
Heading Depth: 3
Heading Rank: 3

Heading: Case Agent as Expert

Text: 19 Appellants argue that Biggs's dual roles as case agent and expert witness allowed him to serve as a summary witness, improperly testifying as an expert about the general meaning of conversations and the facts of the case. We agree that the use of the case agent as an expert increases the likelihood that inadmissible and prejudicial testimony will be proffered. While expert testimony aimed at revealing the significance of coded communications can aid a jury in evaluating the evidence, particular difficulties, warranting vigilance by the trial court, arise when an expert, who is also the case agent, goes beyond interpreting code words and summarizes his beliefs about the defendant's conduct based upon his knowledge of the case. 20 First, as we have observed elsewhere, when a fact witness or a case agent also functions as an expert for the government, the government confers upon him [t]he aura of special reliability and trustworthiness surrounding expert testimony, which ought to caution its use. Young, 745 F.2d at 766 (Newman, J., concurring), cited with approval by Simmons, 923 F.2d at 947. This aura creates a risk of prejudice because the jury may infer that the agent's opinion about the criminal nature of the defendant's activity is based on knowledge of the defendant beyond the evidence at trial, a risk that increases when the witness has supervised the case. Id. Simply by qualifying as an expert, the witness attains unmerited credibility when testifying about factual matters from first-hand knowledge. Additionally, when the expert bases his opinion on in-court testimony of fact witnesses, such testimony may improperly bolster that testimony and may suggest[] to the jury that a law enforcement specialist ... believes the government's witness[] to be credible and the defendant to be guilty, suggestions we have previously condemned. United States v. Cruz, 981 F.2d 659, 663 (2d Cir. 1992) (citing United States v. Scop, 846 F.2d 135, 139-43 (2d Cir.1988)). 21 Second, expert testimony by a fact witness or case agent can inhibit cross-examination, thereby impairing the trial's truth-seeking function. In general, impeaching an expert is difficult. The expert usually has impressive credentials, and he is providing an opinion that, unlike a factual matter, is not easily contradicted. Challenges to the expert are often risky because they can backfire and end up bolstering the credibility of the witness. Normally, this is an acceptable risk for the defense, because only the witness's expertise is at stake. However, when the expert is also a fact witness, the risks are greater. A failed effort to impeach the witness as expert may effectively enhance his credibility as a fact witness. Because of this problem, a defendant may have to make the strategic choice of declining to cross-examine the witness at all. 22 Third, and of particular relevance to this case, when the prosecution uses a case agent as an expert, there is an increased danger that the expert testimony will stray from applying reliable methodology and convey to the jury the witness's sweeping conclusions about appellants' activities, deviating from the strictures of Rules 403 and 702. Simmons, 923 F.2d at 946-47 n. 5. Although we approve of testimony interpreting drug code words, such expert testimony, unless closely monitored by the district court, may unfairly provid[e] the government with an additional summation by having the expert interpret the evidence, and may come dangerously close to usurping the jury's function. Nersesian, 824 F.2d at 1308; see also United States v. Rivera, 22 F.3d 430, 434 (2d Cir.1994); Simmons, 923 F.2d at 947. As the testimony of the case agent moves from interpreting individual code words to providing an overall conclusion of criminal conduct, the process tends to more closely resemble the grand jury practice, improper at trial, of a single agent simply summarizing an investigation by others that is not part of the record. Such summarizing also implicates Rule 403 as a needless presentation of cumulative evidence and a waste of time. Fed.R.Evid. 403. 23 Under Daubert and Rule 702, expert testimony should be excluded if the witness is not actually applying expert methodology. Incorporating the Daubert standard, the amended Rules of Evidence require that expert testimony be based on sufficient facts or data and on reliable principles and methods that the expert witness has applied reliably to the facts of the case. 4 Fed.R.Evid. 702. The Advisory Committee Notes to revised Rule 702 now state that, 24 when a law enforcement agent testifies regarding the use of code words in a drug transaction, .... [t]he method used by the agent is the application of extensive experience to analyze the meaning of the conversations. So long as the principles and methods are reliable and applied reliably to the facts of the case, this type of testimony should be admitted. 25 Fed.R.Evid. 702 advisory committee's notes. When an expert is no longer applying his extensive experience and a reliable methodology, Daubert teaches that the testimony should be excluded. Even if the testimony is admissible under Rule 702, it still must pass muster under Rule 403: Its probative value must not be substantially outweighed by unfair prejudice. See Young, 745 F.2d at 765-66 (Newman, J., concurring). 26 Straying from the scope of expertise may also implicate another concern under Rule 403, juror confusion. Some jurors will find it difficult to discern whether the witness is relying properly on his general experience and reliable methodology, or improperly on what he has learned of the case. When the witness is a case agent who testifies about the facts of the case and states that he is basing his expert conclusions on his knowledge of the case, a juror understandably will find it difficult to navigate the tangled thicket of expert and factual testimony from the single witness, thus impairing the juror's ability to evaluate credibility. 27 Throughout much of Biggs's testimony, his conclusions appear to have been drawn largely from his knowledge of the case file and upon his conversations with co-conspirators, rather than upon his extensive general experience with the drug industry. The district court properly established initial limits on Biggs's testimony that complied with relevant circuit precedent. However, when Biggs strayed beyond those limits, and when defense counsel objected, the district court did not enforce them and thus failed to fulfill its gatekeeping function. We find that the district court erred in allowing Biggs to stray from his proper expert function. Biggs acted at times as a summary prosecution witness; the effect was a bolstering of the testimony of the cooperating co-defendants and an impinging upon the exclusive function of the jury. 28 Biggs's testimony illustrates two examples of how an expert on drug code can stray from the scope of his expertise. First, he testified about the meaning of conversations in general, beyond the interpretation of code words. This testimony often interpreted pronouns and completely ambiguous statements that were patently not drug code. For example, when Biggs testified that the statement what's left over there in that can referred to probably... bundles of heroin, he essentially used his knowledge of the case file and witness interviews that the participants in the conversation were heroin dealers to conclude that they were discussing heroin. Although the same conversation included references to sandwich bags and lighters, and an expert could admissibly explain to a jury the use of lighters and sandwich bags in the drug trade, the permissible scope of Biggs's expert testimony on the tapes was the interpretation of drug code, and what's left over there in that can is plainly not code. Biggs also testified that when Leonard Miller told McGee not to give him ... no more than one or two, Miller was telling McGee not to give Big Dog any more than one or two bundles of heroin, and that when McGee said to Leonard Miller make sure you get your thing, your new one, he was referring to the next supply of heroin. Again, these statements plainly were not drug code. 29 Second, Biggs interpreted ambiguous slang terms that only at first glance might appear to be code or jargon. For example, Biggs testified that McGee's statement tell `em to bring ... the six or whatever' referred to a quantity of heroin, and McGee's statement tell him to come with the ten meant that he requested a quantity of heroin, probably ten bundles. Six and ten may have been veiled references to drugs, but it appears that these phrases were ambiguous in the way that the generic your thing, what's over there, and one or two were ambiguous. There was no evidence that these phrases were drug code with fixed meaning either within the narcotics world or within this particular conspiracy, in the way that B-licks and spider were consistent drug jargon or code. As we discuss below, there is a high risk that when a case agent/expert strays from the scope of his expertise, he may impermissibly rely upon and convey hearsay evidence. See infra Subsection 4. 30 We recognize that the problems we have highlighted do not arise solely in expert testimony by case agents and fact witnesses; any expert in a criminal trial has the potential to deviate from the scope of his expertise. However, these difficulties are more likely to be encountered when the expert is a case agent or a fact witness because such witnesses are introduced to the case primarily through an investigative lens, rather than a general methodological lens. Case agent experts who are called to testify about both their expert opinions and the facts of the case may easily elide these two aspects of their testimony. Given their role, their perspective, and their focus on the facts, these case agent experts are more likely to stray from the scope of their expertise and to testify about other aspects of the case, including the divulging of hearsay evidence. 31 We have been aware of the heightened risk of allowing case agents to testify as experts, but nevertheless have permitted such testimony. See, e.g., United States v. Feliciano, 223 F.3d 102, 121 (2d Cir.2000) (Such dual testimony is not objectionable in principle); Young, 745 F.2d at 760 ([I]t was not improper for the government to elicit ... expert testimony from law enforcement officers who also testified as fact witnesses.). Although we decline to prohibit categorically the use of case agents as experts, we note that the Federal Rules of Evidence and the Supreme Court place the responsibility upon the district courts to avoid falling into error by being vigilant gatekeepers of such expert testimony to ensure that it is reliable, see Kumho Tire Co. v. Carmichael, 526 U.S. 137, 147-49, 119 S.Ct. 1167, 143 L.Ed.2d 238 (1999) (interpreting Daubert, 509 U.S. at 589-92, 113 S.Ct. 2786), and not substantially more unfairly prejudicial than probative. 32 We also note that proper application of the rules of discovery will encourage the prosecution to limit the scope of the expert testimony by a case agent or a fact witness. Rule 16 provides markedly broader discovery with respect to expert witnesses for the government than is required for other types of information from the government. Rule 16 provides that the defense is entitled to discovery of a written summary of expert testimony that the government intends to use in its case-in-chief. Fed.R.Crim.P. 16(a)(1)(G). 5 That summary must describe the witness's opinions, the bases and the reasons for those opinions, and the witness's qualifications. Id. This disclosure requirement creates an incentive for the government to limit its use of experts to proper subject matters of expert testimony, lest broader expert testimony require broader pre-trial disclosure.