United States v. Atkins: No Plain-Error Relief for Unobjected-to Lay Opinion Implying Guilt Without a Showing of Prejudice

Introduction

United States v. Atkins (10th Cir. Mar. 3, 2026) arises from a late-night shooting outside the Tulsa Trip gas station. Defendant-Appellant Marco Dionte Atkins shot Terry Brown multiple times during a confrontation captured on security video. Atkins was convicted by a jury of assault with a dangerous weapon with intent to do bodily harm in Indian Country, a related firearm offense under 18 U.S.C. § 924(c), and multiple counts of witness tampering and obstruction.

On appeal, Atkins raised a single evidentiary issue: the district court did not sua sponte exclude testimony by the Government’s case agent (ATF Agent Ben Nechiporenko) about his review of the surveillance footage and whether that review changed his “opinion” in the investigation— testimony Atkins characterized as improper lay opinion effectively telling the jury the Government believed Atkins was guilty. Because Atkins did not object at trial, the Tenth Circuit reviewed only for plain error.

Summary of the Opinion

The Tenth Circuit affirmed. The panel assumed without deciding that the agent’s testimony plainly violated Federal Rule of Evidence 701(b) (helpfulness requirement for lay opinions), but held that any such error did not affect Atkins’ substantial rights under the third prong of plain-error review.

The court emphasized the strength of the evidence against Atkins (including his admission that he shot Brown, testimony contradicting self-defense, and jail calls undermining the viability of the self-defense theory), the lack of prosecutorial emphasis on the challenged testimony in closing, and the relatively short deliberation time. Accordingly, no reasonable probability existed that the verdict would have been different without the testimony.

Analysis

Precedents Cited

• United States v. Schulte, 741 F.3d 1141 (10th Cir. 2014)
  Role in Atkins: Cited for the standard appellate posture after a jury conviction: the court “draw[s] the facts from the evidence presented at trial in the light most favorable to the government.” This framing matters because the appellate evaluation of prejudice (whether the verdict likely changed) is informed by the trial record viewed favorably to the prosecution.
• United States v. Moya, 5 F.4th 1168 (10th Cir. 2021)
  Role in Atkins: Supplies the four-prong plain-error framework and reinforces that the court may affirm on any prong. Atkins turns principally on prong three (“substantial rights”), illustrating a common appellate pathway: even if error is assumed and plain, the absence of prejudice ends the inquiry.
• United States v. Maryboy, 138 F.4th 1274 (10th Cir. 2025)
  Role in Atkins: Provides the operative prejudice test for prong three: substantial rights are affected only if there is a “reasonable probability” that the result would have been different absent the error; i.e., whether the jury would still have convicted without the error. The Atkins court applies this test directly to the agent’s testimony, concluding the remaining evidence was sufficiently strong.
• United States v. Brooks, 736 F.3d 921 (10th Cir. 2013)
  Role in Atkins: Quoted (via a footnote) for the purpose of Rule 701(b): excluding opinions where the witness is no better suited than the jury, preventing testimony that “merely tell[s] the jury what result to reach.” This is the core concern in Atkins—law-enforcement “opinion” testimony that can function as a proxy for guilt assessment.
• United States v. Meises, 645 F.3d 5 (1st Cir. 2011)
  Role in Atkins: Quoted within United States v. Brooks for the same Rule 701(b) principle. Its inclusion underscores that the “helpfulness” requirement is not satisfied by conclusory judgment calls that invade the jury’s province.
• United States v. Bush, 405 F.3d 909 (10th Cir. 2005)
  Role in Atkins: Used as a contrast showing when lay opinion can be “helpful”—e.g., a detective identifying a voice when the jury lacks an independent basis for comparison because the defendant did not testify. In Atkins, by contrast, the jury itself saw the video and heard contested testimony about whether Brown drew first; thus, the “helpfulness” of an agent’s “opinion” is suspect.
• United States v. Griffith, 65 F.4th 1216 (10th Cir. 2023)
  Role in Atkins: Cited for a practical indicator of prejudice: when prosecutors highlight disputed evidence in closing argument, that emphasis can suggest an impact on the outcome. The Atkins court noted the absence of such emphasis, weighing against a finding of prejudice.

Legal Reasoning

1. Standard of review controlled the outcome.
   Because Atkins did not object at trial, the issue was not preserved for ordinary evidentiary review. Under plain-error review, the defendant must satisfy all four prongs, and failure at any prong defeats relief.
2. The court sidestepped definitive Rule 701(b) error analysis.
   Rather than deciding whether the testimony was admissible lay opinion, the panel assumed (for the sake of argument) that it was a plain violation. This reflects an efficiency principle of plain-error doctrine: appellate courts often resolve cases at prong three when the record shows no prejudice.
3. No “reasonable probability” of a different verdict.
   Applying United States v. Maryboy, the court held Atkins could not show the agent’s testimony tipped the scales on self-defense. Key record facts supporting no prejudice included:
   • Atkins admitted shooting Brown four times.
   • Only Atkins and his sister supported the claim that Brown pulled a gun first; Brown denied it.
   • Other witnesses (Moore and Evans) described no altercation and no threatening behavior by Brown, and Moore did not view Brown as a threat.
   • Jail calls undermined self-defense (Atkins told his mother self-defense “wouldn’t work”).
4. Context minimized the challenged testimony’s force.
   The panel also observed that (a) the agent did not explicitly testify “Atkins is guilty” or “should be prosecuted,” (b) it was undisputed that Brown was armed, a fact consistent with Atkins’ defense rather than necessarily harmful to it, and (c) the testimony was irrelevant to the post-complaint witness-tampering/obstruction counts, limiting any conceivable effect beyond the self-defense dispute.
5. Practical indicators reinforced the no-prejudice conclusion.
   Citing United States v. Griffith, the court noted the Government did not rely on the agent’s disputed testimony in closing argument and the jury returned verdicts on eight charges across two defendants after less than four hours—circumstances the panel viewed as consistent with strong evidence and limited risk that a single snippet of testimony drove the verdict.

Impact

Although designated as a non-precedential “Order and Judgment,” United States v. Atkins provides persuasive guidance on how the Tenth Circuit is likely to handle unpreserved Rule 701(b) challenges to law-enforcement “opinion” testimony that arguably implies guilt:

• Plain-error prong three is the critical battleground. Even where an appellate court is willing to assume a plain Rule 701(b) violation, reversal will be unlikely without a concrete showing that the testimony plausibly changed the verdict.
• Courts will look for corroborating signs of influence. Prosecutorial emphasis in closing, jury difficulty (questions, deadlock, long deliberations), and a thin evidentiary record may matter more than the abstract impropriety of the opinion.
• Defense counsel must object contemporaneously. Atkins is a cautionary example: a timely objection could have triggered a direct admissibility ruling, a limiting instruction, or exclusion—avoiding the steep prejudice burden imposed by plain-error review.
• Limits on “case agent” narration remain salient. The opinion reflects judicial sensitivity to testimony that edges toward “charging decisions” or guilt assessment, even if the panel ultimately resolves the case on harmlessness/prejudice grounds.

Complex Concepts Simplified

Federal Rule of Evidence 701(b) (Lay opinion “helpfulness”)

Non-expert witnesses can sometimes offer opinions, but only if the opinion helps the jury understand the witness’s testimony or decide a fact in issue. An opinion that effectively tells the jury “the defendant is guilty” is typically not “helpful” because jurors are supposed to make that judgment themselves.

Plain-error review

When a party fails to object at trial, an appellate court will reverse only if (1) there was an error, (2) it was clear/obvious (“plain”), (3) it likely affected the outcome (“substantial rights”), and (4) it seriously harms the fairness or integrity of the proceedings. Missing any one prong defeats the appeal.

“Substantial rights” / “reasonable probability”

This is an outcome-focused question: is there a realistic chance the jury would have acquitted (or otherwise reached a different result) if the challenged evidence had been excluded? If the remaining evidence is strong, courts often find no prejudice.

Self-defense at trial (as relevant here)

Atkins admitted the shooting but claimed justification. The jury had to decide whether the shooting was legally justified based on contested facts (e.g., whether Brown drew and threatened first). The appellate court concluded the agent’s testimony did not materially affect that determination.

Conclusion

United States v. Atkins reinforces a practical rule in unpreserved evidentiary disputes: even if law-enforcement lay opinion testimony arguably crosses Rule 701(b)’s line by implying guilt, an appellant must still demonstrate a reasonable probability of a different verdict to obtain relief on plain-error review. The decision highlights the centrality of the prejudice inquiry, the importance of timely objections to “case agent” opinion testimony, and the appellate court’s reliance on the overall evidentiary record—especially where the defendant admits the core act and the contested issue turns on credibility and surrounding circumstances.