Silence Is Plain Error: Sixth Circuit Vacates Sentence Where District Court Fails to Identify Applied Guideline Enhancements (United States v. Jacobs)

Introduction

In United States v. Jacobs, No. 24-3165 (6th Cir. Dec. 3, 2024) (not recommended for publication), the Sixth Circuit affirmed a series of trial rulings and a § 924(c) conviction arising from a string of armed robberies in Columbus, Ohio, but vacated the sentence and remanded. Writing for the panel, Judge Thapar held that although challenges to fingerprint evidence and the court’s answer to a jury question lacked merit—and the evidence was sufficient to support a brandishing conviction—the district court committed plain procedural error by announcing a total offense level without identifying the Guidelines enhancements it applied. That failure to articulate the basis for the Guidelines calculation required vacatur and remand for clarification.

The opinion addresses four issues:

Admissibility of latent fingerprint identification under the ACE-V methodology without a Daubert hearing;
The district court’s direct answer to a deliberating jury’s question about whether two known fingerprints came from the same person;
Sufficiency of the evidence that the defendant brandished a firearm during a Hobbs Act robbery for purposes of 18 U.S.C. § 924(c); and
Procedural reasonableness at sentencing where the court failed to identify which enhancements yielded the total offense level and resulting Guidelines range.

Summary of the Opinion

Fingerprint evidence and Daubert hearing: No abuse of discretion. The district court permissibly admitted ACE-V latent fingerprint testimony without holding a Daubert hearing, rejecting an outdated reliability challenge.
Jury question about known fingerprints: Even assuming error, no prejudice. The court’s “yes” answer—that two sets of known prints belonged to the same person—did not usurp the jury’s role because that fact was undisputed and indisputable on the record.
Sufficiency for § 924(c) brandishing: Affirmed. Eyewitness testimony, corroborating officer testimony, and the defendant’s own admissions more than sufficed (particularly under the heightened “manifest miscarriage of justice” standard given the lack of a renewed Rule 29 motion).
Sentencing: Vacated and remanded. The district court’s pronouncement of an offense level of 28 lacked an on-the-record explanation identifying the enhancements used. That omission amounted to plain error requiring remand for clarification of the applied enhancement(s).

Analysis

Precedents and Authorities Cited

The panel’s reasoning draws on a familiar set of evidentiary, sufficiency, and sentencing precedents:

Daubert/Kumho Tire framework: DAUBERT v. MERRELL DOW PHARMACEUTICALS, INC., 509 U.S. 579 (1993), and KUMHO TIRE CO. v. CARMICHAEL, 526 U.S. 137 (1999), establish the trial court’s gatekeeping role and flexibility, emphasizing that methodology reliability—not conclusions alone—drives admissibility. The panel underscores Kumho Tire’s recognition that in “ordinary cases” the reliability of well-established methods may be “taken for granted.”
No automatic hearing: Clay v. Ford Motor Co., 215 F.3d 663, 667 (6th Cir. 2000), confirms that a Daubert hearing is not mandatory whenever reliability is challenged; courts may decide on the papers where the challenge raises no novel or serious dispute.
ACE-V case law: Courts have repeatedly upheld ACE-V latent fingerprint analysis post-Daubert, including the First Circuit, United States v. Pena, 586 F.3d 105, 110–11 (1st Cir. 2009), and the Third Circuit’s exhaustive review in United States v. Mitchell, 365 F.3d 215, 233–46 (3d Cir. 2004). The opinion observes that courts have rejected attacks premised on an older National Institute of Justice (NIJ) article (see United States v. Crisp, 324 F.3d 261 (4th Cir. 2003)), and cites NIJ’s later synthesis of the 2011 FBI “Black Box” study estimating a 0.1% false positive rate.
Jury-questions standard: United States v. Davis, 970 F.3d 650, 662 (6th Cir. 2020), provides the abuse-of-discretion review for responses to deliberating-jury questions and requires prejudice for reversal.
Sufficiency and preservation: United States v. Davis, 473 F.3d 680, 681 (6th Cir. 2007), supplies the rational-factfinder standard, with the evidence viewed in the light most favorable to the government. Because Jacobs did not renew his Rule 29 motion, United States v. Dunnican, 961 F.3d 859, 877 (6th Cir. 2020), imposed the “manifest miscarriage of justice” threshold. Hobbs Act robbery remains a “crime of violence” under circuit law: United States v. Camp, 903 F.3d 594, 597 (6th Cir. 2018).
Sentencing explanations and plain error: Gall v. United States, 552 U.S. 38, 51 (2007), and United States v. Mack, 808 F.3d 1074, 1084 (6th Cir. 2015), frame procedural reasonableness (accurate calculation and adequate explanation). United States v. Fowler, 819 F.3d 298, 306 (6th Cir. 2016), cautions that appellate courts cannot supply reasons the district court did not give. Given Jacobs’s lack of objection below, United States v. O’Lear, 90 F.4th 519, 535 (6th Cir. 2024), sets plain-error review. The panel also cites Conwood Co. v. U.S. Tobacco Co., 290 F.3d 768, 781 (6th Cir. 2002), for abuse-of-discretion “clear error of judgment” language in the evidentiary context.
Prior appeal in the same case: The court notes its earlier decision, United States v. Jacobs, 63 F.4th 1055, 1060 (6th Cir. 2023), upholding the voluntariness of Jacobs’s confession, clearing the way for trial.

Legal Reasoning and Application

1) ACE-V fingerprint evidence without a Daubert hearing

The defense mounted a reliability attack on ACE-V latent fingerprint identifications, highlighting the lack of probabilistic testing and error-rate data and citing two decades-old sources calling for more research. The district court denied a Daubert hearing, concluding this was an “ordinary case” in which the reliability of the methodology could be taken for granted and noting the uniform acceptance of ACE-V in federal courts over the past thirty years.

On appeal, the panel affirmed. The Sixth Circuit reiterates several key points:

Courts have consistently upheld ACE-V under Daubert/Kumho; challenges premised on dated critique do not create a novel or serious reliability question.
Daubert hearings are discretionary; a court may decide admissibility on the submissions where the method is well accepted.
Recent NIJ commentary summarizing the 2011 FBI “Black Box” study supports the methodology’s low false-positive rate, further undercutting claims of unreliability.

The court found no “clear error of judgment” in skipping a hearing and admitted the testimony of the government’s examiner, who compared latent prints recovered from gum packaging with two sets of Jacobs’s known prints using ACE-V.

2) The court’s answer to the jury’s fingerprint question

During deliberations, jurors asked whether the two known-print exemplars shown in the government’s slides (labeled “185417GD” and “165329DC”) came from the same person. The government urged a simple “yes,” noting authenticity was uncontested and the question did not ask whether the known and latent prints matched—the ultimate issue for the jury. The defense asked the court to refer the jury back to its collective memory. The court did both: answering “yes” while reminding the jurors to rely on their collective memory.

The Sixth Circuit declined to reverse. Even without deciding whether the answer was an abuse of discretion, the panel found no prejudice. The record indisputably established that both known sets were Jacobs’s (from a prior conviction and his arrest in this case). As Davis (2020) recognizes, where there is “literally zero contradictory evidence in the record,” a clarifying answer on an uncontested point does not prejudice the defense. The answer did not resolve the core disputed fact—whether the latent prints matched Jacobs—leaving that determination to the jury.

3) Sufficiency of the evidence for brandishing under § 924(c)

Jacobs challenged the sufficiency of the evidence that he brandished a firearm during the Wing Snob robbery, citing blurry footage, concealment of the weapon, and a single eyewitness. Because he failed to renew his Rule 29 motion, he faced the demanding “manifest miscarriage of justice” standard.

The panel held the evidence easily sufficed:

The shift manager testified she saw a gun and described it (“single barrel on the smaller end,” “looked like a rifle”), identified it in surveillance stills, and explained hearing “metal against metal” as it contacted the robber’s zipper.
An officer relayed a contemporaneous report that the robber was “concealing a black rifle,” corroborating the eyewitness account.
Jacobs’s own statements further incriminated him: on video he said “[t]he weapons, they gone,” and explained he covered a shotgun with clothing because it was “too big.”

Under the deferential viewing standard and the heightened preservation bar, the combination of eyewitness testimony, officer corroboration, and admissions is more than adequate to support the verdict.

4) Sentencing: failure to identify applied enhancements is plain error

The Guidelines math was the one issue that stuck. Everyone agreed that the base offense level for Hobbs Act robbery is 20 (U.S.S.G. § 2B3.1(a)). The presentence report proposed multiple enhancements: +5 for brandishing a firearm (§ 2B3.1(b)(2)(C)), +2 for physical restraint (§ 2B3.1(b)(4)(B)), +2 for obstruction (§ 3C1.1), and a multi-count adjustment of +5 (§ 3D1.4). The court sustained Jacobs’s objections to the firearm and obstruction enhancements and found the restraint enhancement applied to count two, yielding a highest adjusted offense level of 22. Combining that with the +5 multi-count adjustment would produce a total offense level of 27 and a range of 78–97 months (before any mandatory consecutive § 924(c) term).

Yet the court announced an offense level of 28 and a range of 87–108 months. The government had argued for a fallback +3 enhancement for brandishing/possessing a dangerous weapon (§ 2B3.1(b)(2)(E)) if the +5 firearm enhancement did not apply—an approach that would push the highest adjusted offense level to 23 and, with the +5 multi-count adjustment, land on 28. But the district court never said on the record that it was applying the +3 enhancement. It consulted off the record with the probation officer and simply stated the bottom line (28). Tellingly, the government preserved an objection to the court’s “declining to impose the dangerous weapon enhancement,” indicating that even the parties were unsure what the court had done.

That lack of clarity was fatal. Citing Fowler, the panel emphasized that appellate courts cannot supply reasons the district court failed to give. Because the district court “didn’t just fail to give an adequate explanation”—it “failed to identify what enhancements it applied”—the omission amounted to plain error under O’Lear. The sentence was vacated and remanded for the court to clarify which enhancement(s) it used and to explain its calculation.

Impact and Practical Significance

On forensic evidence litigation (ACE-V and Daubert)

The Sixth Circuit remains aligned with the national consensus that ACE-V latent fingerprint analysis is generally reliable under Daubert/Kumho. Absent a novel methodological challenge or case-specific reasons to doubt reliability, trial courts may rule without a hearing.
Practitioners raising Daubert challenges to ACE-V need more than generalized, dated critiques. Empirical developments such as the FBI “Black Box” error-rate studies, as noted by NIJ, undermine broad-brush reliability attacks.
Gatekeeping is still required; the key is framing a challenge that meaningfully implicates Daubert factors in the context of the specific examination and examiner.

On judicial responses to jury questions

Courts may directly answer clarifying questions about undisputed facts without usurping the jury’s role—provided the answer does not resolve contested issues. Prejudice remains the touchstone on appeal.
Record preservation matters. If the defense views the fact as disputed, it should clearly say so at the time and explain the basis in the evidentiary record.

On § 924(c) brandishing proof

Eyewitness testimony, corroboration from responding officers, and defendant admissions can readily support a brandishing conviction—even if the gun is partially concealed—so long as the evidence shows the presence of a firearm was made known to intimidate.
Failure to renew a Rule 29 motion imposes a steep appellate burden; practitioners should always renew to preserve de novo sufficiency review.

On sentencing explanations: a bright-line caution

New emphasis: This opinion sharpens the Sixth Circuit’s existing insistence on transparent Guidelines calculations by holding that failure to identify which enhancements produce the total offense level is plain error requiring vacatur—even absent a contemporaneous defense objection.
District courts must do more than state the offense level and range. They should:
- Identify each enhancement and its Guideline provision;
- State which ones apply (and which do not) and why;
- Show the arithmetic from the base offense level through the combined adjusted level, including § 3D1.4 units; and
- Avoid off-the-record consultations that leave ambiguity in the transcript.
Where a § 924(c) count is present, courts should expressly address Application Note 4 to § 2K2.4 (no weapon SOCs for the underlying offense of the § 924(c) count) and clarify if weapon enhancements are being applied to other grouped counts. Although not disputed here, Jacobs illustrates how unclear cross-count application can cloud the record.
Appellate posture: Even on plain-error review, opaque Guidelines calculations are vulnerable. Defense counsel should object if the court does not identify enhancements; the government should seek clarification to protect the record.

Complex Concepts Simplified

ACE-V: A four-step process—Analysis, Comparison, Evaluation, and Verification—used by fingerprint examiners to compare latent (crime-scene) prints to known exemplars.
Latent vs. known fingerprints: Latent prints are unintentionally left on objects; known prints are deliberately recorded from a known individual (e.g., inked or scanned).
Daubert hearing: An evidentiary hearing to assess expert-method reliability. Not automatic; courts may rule on the submissions for well-accepted methods.
Brandishing (18 U.S.C. § 924(c)): Displaying all or part of a firearm, or otherwise making its presence known, to intimidate during a crime of violence or drug trafficking crime. A seven-year mandatory consecutive term applies when brandishing is proven.
Rule 29 motion: A motion for judgment of acquittal based on insufficient evidence. Failing to renew after presenting defense evidence triggers a stricter appellate standard (manifest miscarriage of justice).
Guidelines enhancements cited:
- § 2B3.1(b)(2)(C): +5 if a firearm is brandished or possessed during a robbery;
- § 2B3.1(b)(2)(E): +3 if a dangerous weapon is brandished or possessed;
- § 2B3.1(b)(4)(B): +2 for physical restraint of a victim;
- § 3C1.1: +2 for obstruction of justice;
- § 3D1.4: Multi-count adjustment (units) added to the highest adjusted offense level.
Procedural reasonableness: A sentence must be based on correct Guidelines calculations and a sufficient on-the-record explanation of the chosen sentence.
Plain error: Appellate relief standard when no objection was made below, requiring an error that is clear, affects substantial rights, and seriously affects the fairness, integrity, or public reputation of judicial proceedings.
“Not recommended for publication”: Under Sixth Circuit rules, such opinions are not binding precedent but may be cited for persuasive value.

Conclusion

United States v. Jacobs delivers four practical messages. First, ACE-V latent fingerprint identifications remain admissible in the Sixth Circuit without a Daubert hearing where the challenge is generic and the methodology is well established. Second, trial courts may directly clarify undisputed facts when responding to a deliberating jury—absent prejudice, such responses will be upheld. Third, eyewitness testimony corroborated by officer reports and defendant admissions easily sustains a § 924(c) brandishing conviction, even if the firearm is partially concealed. Fourth—and most consequential for future cases—the Sixth Circuit will not tolerate opaque Guidelines calculations. When a district court pronounces a total offense level without identifying which enhancements got it there, that omission is plain error warranting vacatur and remand.

Though not precedential, Jacobs is a clear, teachable opinion: it reinforces evidentiary stability for ACE-V fingerprint analysis, underscores careful jury communications, and, above all, insists on transparent, on-the-record sentencing arithmetic. On remand, the district court must specify whether the three-level dangerous-weapon enhancement under § 2B3.1(b)(2)(E) was applied and reconcile the total offense level accordingly. Going forward, district courts in the Sixth Circuit should make explicit each step of the Guidelines calculation to avoid the same fate.