Crossing The Boundaries Of Permissible Expert Testimony

Second Circuit reverses gang convictions based on erroneous law enforcement expert testimony, which included inadmissible testimony on factual matters; merely repeating hearsay statements without using expertise to reach an opinion; and repeating and summarizing the testimonial statements of others violated the Confrontation Clause, in United States v. Mejia, 545 F.3d 179 (2d Cir. Oct. 6, 2008) (Nos. 05-2856-cr, 05-6683-cr(CON), 06-1744-cr(CON))

The Second Circuit recently highlighted the boundaries of law enforcement expert opinion in a gang prosecution involving two drive-by shootings. Because the expert crossed the line, the convictions were reversed on appeal.

In Mejia, a New York State Police investigator testified about the M-13 (“La Mara Salvatrucha”) gang, including MS-13’s “enterprise structure and the derivation, background and migration of the MS-13 organization, its history and conflicts,” as well as MS-13’s “hierarchy, cliques, methods and activities, modes of communication and slang.” Mejia, 545 F.3d at 186. While the witness was qualified to testify as an expert, based on his training and experience with gangs, he exceeded the scope of expert testimony by testifying on factual matters which did not involve “specialized knowledge,” under FRE 702. Many of the areas were “well within the grasp of the average juror” and expertise was not required to understand the facts. For example, the expert testified that:

  • “[T]he FBI gang task force had seized ‘[p]robably between 15 and 25’ firearms, as well as ammunition, from MS-13 members”;
  • “MS-13 members on Long Island had been arrested for dealing narcotics”;
  • “MS-13 had committed ‘between 18 and 22, 23’ murders on Long Island between June 2000 and the trial”;
  • “[T]he use of MS-13 treasury funds to buy firearms and narcotics”; and
  • “MS-13 taxed non-member drug dealers.” Mejia, 545 F.3d at 195.

The error was compounded by the expert’s reliance on inadmissible hearsay. While FRE 703 allows experts to rely on hearsay, the rule requires that “experts in the field” would “reasonably rely on such [hearsay] evidence in forming their opinions.” Mejia, 545 F.3d at 197 (citing FRE 703). For example, “When asked how he learned particular facts, [officer] Alicea did not explain how he had pieced together bits of information from different sources and reached a studied conclusion that he then gave to the jury. Instead, he testified that he had read an article, or had talked to gang members in custody (including, on at least one occasion, a gang member arrested as part of this investigation), or listened to a recording (evidence that could have been played to the jury in its original form, notwithstanding that some informants may have been identified in the process). This testimony strongly suggests that [officer] Alicea was acting not as an expert but instead as a case agent…. [Officer] Alicea did not analyze his source materials so much as repeat their contents.” Mejia, 545 F.3d at 198.

The expert testimony also violated the Confrontation Clause by repeating and summarizing testimonial statements and without employing his expertise. Mejia, 545 F.3d at 199 (quoting United States v. Lombardozzi, 491 F.3d 61, 73 (2d Cir. 2007) (considering whether the expert “applied his expertise to those statements but did not directly convey the substance of the statements to the jury”)). At least some of the expert testimony was based on testimonial statements, which implicated Crawford v. Washington, 541 U.S. 36 (2004) (before “testimonial” statements may be admitted, the government must show the witness is unavailable and the defense had a prior opportunity to cross-examine). For example, “there was at least one fact to which [investigator] Alicea testified -- the drug tax -- that was based directly on statements made by an MS-13 member in custody (during the course of this very investigation). This impugns the legitimacy of all of his testimony and strongly suggests to us that Alicea was ‘simply summarizing an investigation by others that [was] not part of the record,’ and presenting it ‘in the guise of an expert opinion.’” Mejia, 545 F.3d at 193 (citations omitted). The circuit concluded that the witness’s “reliance on and repetition of out-of-court testimonial statements made by individuals during the course of custodial interrogations violated Appellants’s rights under the Confrontation Clause of the Sixth Amendment.” Mejia, 545 F.3d at 199.

The convictions were reversed and the case was remanded after the circuit concluded the error in admitting the expert testimony was not harmless beyond a reasonable doubt. As the circuit noted, “The Government was required to prove acts and threats of murder as an element of every offense with which Appellants were charged. Apart from [officer] Alicea’s testimony, the Government introduced only circumstantial evidence tending to prove that element; evidence that, though capable of supporting a jury’s finding of guilt, does not compel such a determination.” Mejia, 545 F.3d at 202. As a case contrast, a law enforcement expert did not violate the Confrontation Clause in United States v. Law, 528 F.3d 888 (D.C. Cir. 2008) (per curiam), which was reviewed a few months ago. In Law, a law enforcement officer testified about the manner in which narcotics dealers operate. His opinion was based in part on hearsay statements of numerous narcotics dealers. The Confrontation Clause was not violated in Law because the expert “testified based on his experience as a narcotics investigator; he did not relate statements by out-of-court declarants to the jury.” Law, 528 F.3d at 912.

The problems in Mejia could have largely been avoided. For example, the factual issues on which the expert testified could have been proven through fact witnesses. The expert could have avoided merely repeating hearsay statements without any application of his specialized knowledge. Nonetheless, the case underscores some of the hurdles in using a law enforcement witness as an expert whose testimony is based on hearsay statements.

Federal Rules of Evidence