United States v. Chavez

• Decision Date: 13 December 2021
• Docket Number: 15-CR-00285-LHK-1
• Court: U.S. District Court — Northern District of California
• Parties: UNITED STATES OF AMERICA, Plaintiff, v. DANIEL CHAVEZ, et al., Defendants.

UNITED STATES OF AMERICA, Plaintiff, v. DANIEL CHAVEZ, et al., Defendants.

No. 15-CR-00285-LHK-1

United States District Court, N.D. California, San Jose Division

December 13, 2021

ORDER DENYING CHAVEZ'S AND SKATES' MOTION TO LIMIT PRESENTATION OF BALLISTICS EVIDENCE BY THE UNITED STATES RE: DKT. NO. 941

LUCY H. KOH United States District Judge.

On September 10, 2021, Defendants Daniel Chavez and Victor Skates (collectively, “Defendants”) moved to limit the presentation of ballistics comparison evidence by the United States (“the government”). ECF No 941. (“Mot.”).^[1] The government filed an opposition on October 1, 2021. ECF No. 951 (“Opp'n”). Defendants filed a reply on October 15, 2021. ECF No. 961 (“Reply”). Having considered the filings of the parties, the relevant law, and the record in this case, the Court DENIES Defendants' Daubert motion to limit the presentation of ballistics comparison evidence by the government.

Defendants move to limit the government's ballistic expert testimony under Federal Rule 702 and Daubert v. Merrell Dow Pharms., Inc.¸509 U.S. 579 (1993). Mot at 1. Specifically, Defendants seek to effectively limit any ballistic expert testimony to opinions that “a particular bullet or casing cannot be excluded from having been fired by a particular firearm.” Id. The government contends that ballistic expert testimony easily meet the Daubert standard for admissibility and Defendants rely on outlier rulings. Opp'n at 1-2. The Court agrees with the government.

Federal Rule of Evidence 702 governs the admission of expert testimony and imposes a “gatekeeping obligation” on the district court. See Kumho Tire Co., Ltd. v Carmichael, 526 U.S. 137, 147 (1999). To be admitted expert testimony must be “both relevant and reliable.” United States v. Vallejo, 237 F.3d 1008, 1019 (9th Cir. 2001). Although Defendants do not challenge the relevance of the government's ballistic expert testimony, the Court explicitly finds the government's proposed expert testimony that “a particular bullet or cartridge was fired from a particular gun, ” Opp'n at 1, is relevant to the instant case, which involves “dozens of shootings allegedly committed by alleged Norteño gang members in Salinas, California, ” Mot. at 2. Defendants' own expert agrees. See Mot. at 16 (acknowledging that “the comparison of toolmarks to a particular tool such as a gun are certainly relevant”).

To be reliable, the testimony must have “a reliable basis in the knowledge and experience of the relevant discipline.” Kumho Tire, 526 U.S. at 149 (1999) (citation and alterations omitted). In Daubert, the Supreme Court outlined five factors for the courts to consider when determining whether testimony is reliable: “(1) whether the method has been tested; (2) whether the method ‘has been subjected to peer review and publication;' (3) ‘the known or potential rate of error;' (4) whether there are ‘standards controlling the technique's operation;' and (5) the general acceptance of the method within the relevant community.” United States v. Johnson, 875 F.3d 1265, 1280 (9th Cir. 2017) (quoting Daubert¸ 509 U.S. at 592-95). However, “the reliability inquiry is a flexible one and the district court has broad latitude to determine what factors in Daubert, if any, are relevant to the reliability determination.” United States v. Valencia-Lopez, 971 F.3d 891, 898 (9th Cir. 2020) (cleaned up).

Here, relying primarily on out-of-circuit authority, Defendants challenge the reliability of the Association of Firearm and Toolmark Examiners (“AFTE”) methodology used by firearms identification experts. See, e.g., Mot. at 4-6. The Ninth Circuit has previously rejected similar reliability challenges to AFTE methodology under Daubert. See Johnson, 875 F.3d at 1280-81 (rejecting the argument that “the AFTE is inherently unreliable and fails to satisfy the Daubert factors.”). Moreover, the Ninth Circuit in Johnson found that qualifying the expert's conclusion to a “reasonable degree of ballistics certainty” coupled with allowing the defendant to cross-examine the expert and present a defense ballistics expert witness “provided adequate safeguards to allow the jury to properly evaluate the probative value” of the expert opinion and written report. Id.

The government represents that the government experts will not express identification conclusions with absolute certainty, or even that these conclusions are “held to a reasonable degree of scientific certainty, ” and will not testify that the “identification is being made to the exclusion of all other firearms in the world.” Opp'n at 24. These representations fall comfortably within the safeguards the Ninth Circuit found adequate in Johnson. Defendants however seek to impose two limiting jury instructions that reject the Ninth Circuit's general approval of AFTE methodology in Johnson.

Below, the Court analyzes in turn whether each Daubert factor weighs in favor of reliability. The Court ultimately concludes that even in light of a minority of cases, decided after the Ninth Circuit Johnson decision¸ AFTE methodology is relevant and reliable and that no limiting instruction is necessary.

1. The AFTE Methodology Can and Has Been Tested

The first Daubert factor, whether the relevant technique or method can and has been tested, is a “key question” when deciding whether expert testimony should be admitted. See United States v. Romero-Lobato, 379 F.Supp.3d 1111, 1119 (D. Nev. 2019) (citing Daubert, 509 U.S. 579 at 593). Courts across this country nearly uniformly conclude that AFTE methodology can, and has, been tested. See, e.g., United States v. Johnson¸ No. (S5) 16 Cr. 281 (PGG), 2019 WL 1130258, at *15 (S.D.N.Y. March 11, 2019) (collecting cases and concluding that “[t]here appears to be little dispute that toolmark identification is testable as a general matter”); United States v. Harris, 502 F.Supp.3d 28, 37 (D.D.C. 2020) (collecting cases concluding that “firearm toolmark identification can be tested and reproduced”); United States v. Diaz, 2007 WL 485967 at *5 (N.D. Cal. 2007) (holding that the theory of firearms identification, though based on examiners' subjective assessment of individual characteristics, “has been and continues to be tested”). Even in United States v. Tibbs, the primary case on which defendant relies, the court concluded that “virtually every court that has evaluated the admissibility of firearms and toolmark identification has found the AFTE method to be testable and that the method has been repeatedly tested.” No. 2016-CF1-19431, 2019 WL 4359486 at *7 (D.C. Super. Ct. Sept. 5, 2019) (collecting cases). The Court agrees with these cases and finds this factor weighs in favor of admissibility.

Defendant's reliance on United States v. Adams, 444 F.Supp.3d 1248, 1259-60 (D. Or. 2020), is unpersuasive. Although in Adams the court found the AFTE method was not testable, the Adams court failed to engage with, much less, distinguish the reasoning in any of the previous cases that found the AFTE methodology has and can be tested. As other courts have noted, “[t]he fact that numerous studies have been conducted testing the validity and accuracy of the AFTE method” strongly suggests the method has and can be tested. See Romero-Lobado, 379 F.Supp.3d at 1119; see also Harris, 502 F.Supp.3d at 37 (“The fact that there are subjective elements to the firearm and toolmark identification methodology is not enough to show that the theory is not ‘testable.'”)

2. The AFTE Methodology Has Been Subject to Peer Review and Publication

Under the second Daubert factor, the Court considers whether the AFTE method has been subject to “peer review and publication.” Daubert, 509 U.S. at 594. Similar to the first factor, courts considering challenges to the AFTE methodology have nearly uniformly concluded that this factor has been satisfied. See Tibbs, 2019 WL 4359486, at *9 (collecting cases and noting that other courts have found that “publication in the AFTE Journal satisfies this prong of the admissibility analysis). The court again agrees with the weight of authority and finds this factor weighs in favor of admissibility.

Defendants rely on two unpersuasive cases, Tibbs and Adams, to suggest that existing literature on the AFTE method is insufficient to meet this Daubert factor. Mot. at 36-42. However, both the Tibbs and Adams courts focused on whether AFTE Journal publications were sufficient to weigh in favor of admissibility. See Tibbs, 2019 WL 4359486 at *10 (“Ultimately, the Court has seen only two meaningfully peer reviewed journal articles regarding the foundational validity of the field, as the vast majority of the studies are published in a journal that uses a flawed and suspect review process.”); Adams, 444 F.Supp.3d at 1265-66 (rejecting reliance on the AFTE Journal because “the purpose of publication in the AFTE Journal is not to review the methodology for flaws but to review studies for their adherence to the methodology.”).

However even if the Court were to fully discount the studies published in the AFTE Journal, these are not the only examples of peer review research published in this field. For example, Defendant's own expert acknowledges that the Journal of Forensic Sciences has published at least three error rate studies of firearm examiners. ECF No. 941-3 (“Scurich Decl.”) ¶¶ 14, 19. Moreover, the two government reports on which Defendants repeatedly rely, the 2009 NAS Report and the 2016 PCAST Report, “themselves constitute peer review despite the unfavorable view the two reports have of the AFTE method.” Romero-Lobato, 379 F.Supp.3d at 1119. In addition, the government's expert provides a non-exhaustive list of over fifty peer-reviewed research published outside of the AFTE Journal. ECF No. 951-2...