United States v. McMillan: Lay Investigative Testimony May Include Common-Sense Inferences; Uncorroborated Accomplice Testimony Can Sustain Conviction; New Rule 29 Grounds Are Forfeited Absent Manifest Miscarriage of Justice

1. Introduction

In United States v. Jalen McMillan (4th Cir. Mar. 30, 2026) (unpublished, per curiam), the Fourth Circuit affirmed the convictions and sentence of Jalen Craig McMillan, a credit-union employee convicted by a federal jury of: conspiracy to commit bank fraud (18 U.S.C. § 1349), three counts of bank fraud (18 U.S.C. § 1344), and aggravated identity theft (18 U.S.C. § 1028A).

The Government alleged a scheme in which McMillan and coconspirators used stolen identities to open credit-union accounts, obtain loans or funds, withdraw proceeds in cash, and distribute the proceeds among participants. On appeal, McMillan challenged: (i) testimony from an investigative financial analyst (arguing it was improper expert testimony), (ii) testimony from a coconspirator (arguing uncorroborated accomplice testimony could not support conviction, invoking Hammer v. United States), and (iii) the denial of his Rule 29 motion (arguing insufficient evidence of knowledge and participation).

2. Summary of the Opinion

The Fourth Circuit affirmed across the board. It held that:

  • The financial analyst’s challenged statements were permissible lay opinion under Rule 701 because they were based on personal perception during the investigation and reflected “common sense” inference rather than specialized expert methodology.
  • The district court did not plainly err in admitting coconspirator testimony; and, as a matter of circuit law, uncorroborated accomplice testimony can sustain a conviction. The court also rejected reliance on Hammer v. United States, limiting Hammer to perjury cases.
  • The denial of the Rule 29 motion was proper. Where the defendant raised only a specific Rule 29 ground at trial (authorship of texts), other sufficiency theories were treated as forfeited absent a “manifest miscarriage of justice,” and the record contained substantial evidence of guilt, including text messages, time sheets, employee-ID audit trails, and coconspirator testimony.

3. Analysis

3.1. Precedents Cited

A. Standards of Review for Evidence Issues

  • United States v. Simmons, 11 F.4th 239, 261 (4th Cir. 2021): Cited for the principle that evidentiary rulings are reviewed for abuse of discretion. This frames the appellate posture: the panel does not reweigh the evidence de novo, but asks whether the district court’s decision fell outside the range of permissible choices.
  • United States v. Cloud, 680 F.3d 396, 401 (4th Cir. 2012): Supplies the harmless-error standard for evidentiary mistakes—reversal is unwarranted if the court can say “with fair assurance” that the judgment was not “substantially swayed.” Even where an evidentiary line is crossed, Cloud limits relief absent meaningful prejudice.
  • United States v. Watkins, 111 F.4th 300, 311 (4th Cir. 2024): Establishes the four-part plain-error test for unpreserved claims (error; clear error; effect on substantial rights; and an effect that seriously undermines the fairness/integrity/reputation of proceedings). This standard governed McMillan’s unpreserved challenge involving coconspirator testimony.

B. Distinguishing Lay and Expert Opinion Testimony

  • Lord & Taylor, LLC v. White Flint, L.P., 849 F.3d 567, 575 (4th Cir. 2017): Quoted for the Rule 701 limitation—lay opinions must not be based on the “scientific, technical, or other specialized knowledge” reserved for Rule 702. This anchored the court’s threshold inquiry: was the analyst’s testimony truly “specialized,” or merely a perception-based inference?
  • Certain Underwriters at Lloyd's, London v. Sinkovich, 232 F.3d 200, 203 (4th Cir. 2000): Emphasizes the “critical distinction” that expert testimony requires specialized knowledge not possessed by jurors. The panel used this to explain the governing conceptual boundary, then concluded the challenged testimony stayed on the lay side of the line.
  • United States v. Perkins, 470 F.3d 150, 156 (4th Cir. 2006): Provides the cautionary principle that Rule 701 forbids “expert testimony dressed in lay witness clothing,” while still allowing lay witnesses to draw inferences. The McMillan panel relied on this balance to approve inference-drawing tied to investigative perception.
  • United States v. Smith, 962 F.3d 755, 768 (4th Cir. 2020): The court quoted Smith to characterize the challenged inference as calling “more for the exercise of common sense than expertise.” This became the decisive descriptor: if a conclusion is reachable by jurors through ordinary reasoning from observed facts, it is more likely admissible as lay opinion even when offered by a trained investigator.

C. Accomplice Testimony and the Misreading of Hammer

  • Hammer v. United States, 271 U.S. 620 (1926): McMillan invoked Hammer for the proposition that a conviction cannot rest on uncorroborated accomplice testimony. The Fourth Circuit rejected this, explaining that Hammer “applies only to cases involving perjury,” which was not at issue. The panel’s use of Hammer is primarily corrective: it limits a commonly misapplied Supreme Court decision to its perjury context.
  • United States v. Robertson, 68 F.4th 855, 863 (4th Cir. 2023): Reaffirms controlling circuit law: “the uncorroborated testimony of an accomplice may be sufficient to sustain a conviction.” This directly disposes of McMillan’s sufficiency theory as to coconspirator Bell’s testimony and signals continuity, not innovation, in Fourth Circuit doctrine.

D. Rule 29 Sufficiency Review and Forfeiture of New Grounds

  • United States v. Burfoot, 899 F.3d 326, 334 (4th Cir. 2018): Sets de novo review for denial of a Rule 29 motion and the “substantial evidence” standard when viewing the evidence in the light most favorable to the prosecution.
  • United States v. Wolf, 860 F.3d 175, 194 (4th Cir. 2017): Reinforces that reversal for insufficient evidence is rare and reserved for clear prosecutorial failure, underscoring the heavy burden a defendant bears on appeal.
  • United States v. Duroseau, 26 F.4th 674, 678 (4th Cir. 2022): Critical to the panel’s handling of McMillan’s Rule 29 issues. Duroseau states that when a defendant raises specific grounds in a Rule 29 motion, other grounds are “waived,” though the Fourth Circuit clarifies “forfeiture” is the more precise term, and newly asserted grounds are reviewed through the “manifest miscarriage of justice” lens.
  • United States v. Rao, 123 F.4th 270, 276 (5th Cir. 2024): Cited (persuasively) for articulation of the “manifest miscarriage of justice” standard: whether the record is devoid of evidence of guilt, or evidence on a key element is so tenuous that conviction would be “shocking.” This illustrates cross-circuit convergence on what “manifest miscarriage” means in practice.
  • United States v. Vinson, 852 F.3d 333, 351 (4th Cir. 2017): Supplies the elements of conspiracy to commit bank fraud: (1) an agreement to commit bank fraud; and (2) knowledge of the criminal objective and willful joining with intent to further it. The panel used Vinson to evaluate whether the Government’s proof met each element.

3.2. Legal Reasoning

A. Why the Financial Analyst’s Testimony Was Treated as Lay Opinion

McMillan argued that Joseph Kropff—an investigative financial analyst not offered as an expert—gave expert testimony in violation of Rules 701/702. The court’s reasoning proceeded in functional terms:

  1. Source of the opinion: The testimony arose from Kropff’s “personal perception of the evidence during his investigation,” i.e., what he reviewed and how it led him to focus on McMillan as a suspect.
  2. Nature of the inference: The conclusion was characterized as “call[ing] more for the exercise of common sense than expertise” (quoting United States v. Smith).
  3. Rule 701 boundary: Under Perkins, Rule 701 bars “expert testimony dressed in lay witness clothing,” but does not forbid all inference-drawing. The panel treated Kropff’s testimony as permissible investigative narration plus common-sense inference, rather than specialized financial-science methodology.

Notably, the panel sidestepped a preservation dispute because it found no error even under the more defendant-friendly preserved-error standard—an approach that conserves judicial resources when the outcome is the same under either standard.

B. Why Bell’s Accomplice Testimony Was Admissible and Sufficient

McMillan’s second argument attempted to turn an evidentiary admission question into a categorical sufficiency bar: he contended Hammer v. United States prevented conviction based on uncorroborated accomplice testimony. The panel addressed both possible readings of his claim:

  • Admissibility: Because McMillan offered no exclusionary rule and none was apparent, the admission of Bell’s testimony was not plain error under United States v. Watkins.
  • Sufficiency: Under United States v. Robertson, accomplice testimony—even uncorroborated—can suffice to sustain a conviction in the Fourth Circuit.
  • Limiting Hammer: The panel further held that Hammer is confined to perjury cases, removing any arguable tension between Hammer and modern accomplice-testimony doctrine in fraud prosecutions.

C. Rule 29: Narrowly Raised Grounds and the Forfeiture/Manifest-Miscarriage Backstop

McMillan’s Rule 29 motion at trial challenged only whether he was the sender of incriminating text messages from his phone. On appeal, he broadened the attack to overall knowledge and participation in the conspiracy. The court applied a two-track analysis:

  1. The preserved ground (texts): The court found substantial evidence that McMillan sent the texts, emphasizing: (i) the phone was seized from his person, (ii) it was passcode-protected, and (iii) the messages coordinated fraudulent transactions contemporaneously and sometimes while McMillan was working at the credit union.
  2. Newly raised grounds (overall knowledge/participation): Under United States v. Duroseau, these theories were forfeited absent a “manifest miscarriage of justice.” The panel—invoking United States v. Rao for the content of that standard— concluded no such miscarriage occurred because the record contained multiple reinforcing forms of proof: the text messages, employee time sheets, credit-union records showing use of McMillan’s employee identification number on fraudulent account paperwork/transactions, and Bell’s detailed account.

Applying United States v. Vinson, the court concluded the evidence supported both the existence of an agreement to commit bank fraud and McMillan’s knowing, willful participation with intent to further the unlawful objective.

3.3. Impact

Although unpublished and therefore “not binding precedent in this circuit,” the decision is still instructive for litigants and trial courts on recurring procedural and evidentiary issues:

  • Rule 701/702 line in white-collar investigations: The case reinforces that investigators (including financial analysts) may offer lay opinions when grounded in personal investigative review and when the inference is one jurors can reach through common sense. Defendants challenging such testimony should identify specific “specialized methodology” or technical reasoning that crosses into Rule 702.
  • Accomplice testimony remains powerful: The panel’s reliance on United States v. Robertson underscores that, absent another legal defect (e.g., due process concerns, improper vouching, or inadmissible hearsay), accomplice testimony alone can support conviction. The opinion also serves as a caution against overreading Hammer v. United States outside the perjury context.
  • Rule 29 practice and appellate posture: The decision highlights a practical lesson: a narrowly framed Rule 29 motion can constrain appellate sufficiency arguments. Under United States v. Duroseau, new sufficiency theories may face the steep “manifest miscarriage of justice” hurdle rather than full merits review.

4. Complex Concepts Simplified

  • Lay vs. expert opinion (Rules 701 and 702): Lay opinion is allowed when it comes from what the witness personally observed and when the conclusion is a commonsense inference. Expert opinion is needed when the witness relies on specialized knowledge or technical methods beyond ordinary juror understanding.
  • Plain error: If a defendant did not object at trial, the appellate court will correct an error only if it is clear, prejudicial, and seriously undermines the fairness or integrity of the proceeding (per United States v. Watkins).
  • Harmless error: Even if the trial court made a mistake, the conviction stands if the appellate court is convinced the mistake did not substantially influence the verdict (per United States v. Cloud).
  • Rule 29 and “substantial evidence”: A Rule 29 motion argues the evidence is legally insufficient. On appeal, courts view the evidence in the light most favorable to the Government and ask whether a reasonable factfinder could find guilt beyond a reasonable doubt (per United States v. Burfoot).
  • Forfeiture and “manifest miscarriage of justice” in Rule 29: If a defendant makes only specific Rule 29 arguments at trial, other sufficiency arguments raised later may be treated as forfeited. The appellate court will intervene only if the record is essentially empty on guilt or the conviction would be “shocking” (drawing on United States v. Duroseau and the articulation quoted from United States v. Rao).
  • Uncorroborated accomplice testimony: In the Fourth Circuit, a cooperating participant’s testimony can, by itself, be enough to convict if the jury finds it credible (per United States v. Robertson).

5. Conclusion

United States v. McMillan affirms a fraud-and-identity-theft conviction by applying three practical doctrines: (1) investigative witnesses may offer lay opinions that reflect perception-based, common-sense inference rather than specialized expert analysis; (2) uncorroborated accomplice testimony can be sufficient to sustain a conviction, and Hammer v. United States does not bar such convictions outside the perjury context; and (3) defendants should raise all intended sufficiency theories in their Rule 29 motions, because new theories on appeal may be treated as forfeited absent a manifest miscarriage of justice. Even as an unpublished disposition, the opinion provides a clear roadmap for how the Fourth Circuit analyzes these recurring evidentiary and procedural issues in complex financial crime prosecutions.