Automatic Deletion Under Neutral Retention Policies Does Not Warrant a Criminal Spoliation Adverse-Inference Instruction Absent Prior Knowledge of Relevance and Willful Loss

I. Introduction

In United States v. Isaac Martinez-Chavez (4th Cir. Sept. 9, 2026), the Fourth Circuit affirmed firearms convictions arising from a New Year’s Day traffic stop in Franklin County, Virginia. The defendant, a convicted felon, was found alone in a Kia containing a sawed-off .22 rifle, a .22 revolver, and .22 ammunition. He was convicted of felon-in-possession under 18 U.S.C. § 922(g)(1) and possession of an unregistered short-barreled rifle under 26 U.S.C. § 5861(d).

On appeal, Martinez-Chavez sought a new trial on two grounds:

  1. Prosecutorial misconduct in closing argument, including an improper “community protection / law enforcement professionalism” appeal and calling a defense witness a “liar.”
  2. Spoliation/adverse inference: the district court’s refusal to instruct the jury that it could draw an adverse inference from the government’s failure to preserve dispatch recordings of the arresting officer’s radio traffic.

The decision is particularly significant for its treatment of criminal spoliation instructions where evidence is lost via automatic deletion under a neutral retention policy, and for its reaffirmation of how the Fourth Circuit evaluates improper closing arguments under harmless-error and plain-error frameworks.

II. Summary of the Opinion

The Fourth Circuit affirmed.

  • The court accepted the government’s concession that two closing remarks were improper, but held that neither remark—individually or cumulatively—prejudiced Martinez-Chavez. The “law enforcement / remove felons from the streets” comment was harmless (preserved objection). The “liar” comment did not satisfy plain error (unpreserved objection).
  • The court held the district court did not abuse its discretion by denying an adverse-inference instruction for the deleted dispatch recordings. Even assuming United States v. Johnson, 996 F.3d 200 (4th Cir. 2021) supplies the governing spoliation standard, Martinez-Chavez failed to show both (i) that the government knew the recordings were relevant to a trial issue before they were deleted, and (ii) that the loss resulted from willful conduct rather than neutral, automatic deletion.

III. Analysis

A. Precedents Cited (and How They Shaped the Decision)

1. Prosecutorial remarks: impropriety + prejudice frameworks

  • United States v. Chorman, 910 F.2d 102 (4th Cir. 1990) and United States v. Brockington, 849 F.2d 872 (4th Cir. 1988)
    These cases provide the court’s baseline test: reversal is warranted only if remarks were improper and “prejudicially affected the defendant’s substantial rights so as to deprive the defendant of a fair trial.” The Martinez-Chavez panel used this standard to separate conceded impropriety from the decisive issue—prejudice.
  • United States v. Harrison, 716 F.2d 1050 (4th Cir. 1983) and United States v. Lighty, 616 F.3d 321 (4th Cir. 2010)
    These cases supply the multi-factor prejudice inquiry (misleading tendency, extent, strength of evidence, diversion to extraneous matters, invitation by defense, and curative instructions), and emphasize that no one factor is dispositive. The panel used these factors to characterize the improper law-enforcement appeal as isolated, counteracted by instructions, and overwhelmed by evidence.
  • United States v. Runyon, 707 F.3d 475 (4th Cir. 2013)
    Runyon is the principal comparator for “send a message” / community-protection arguments. The panel relied on Runyon to label the prosecutor’s “toward that end” appeal improper while also stressing that limiting instructions can “minimize[] any risk” that argument substitutes for evidence—supporting harmlessness here.
  • United States v. Woods, 710 F.3d 195 (4th Cir. 2013)
    Woods is used twice: (i) to confirm that deliberateness alone does not establish prejudice, and (ii) to show that overwhelming evidence defeats claims that improper argument affected the outcome under both harmless-error and plain-error review.
  • Plymail v. Mirandy, 8 F.4th 308 (4th Cir. 2021)
    Martinez-Chavez invoked Plymail to argue that bolstering law enforcement mattered because knowledge was disputed. The panel distinguished Plymail as involving “a pervasive course of vividly improper argument” in a pure credibility contest—unlike this case, where the improper comment was brief and independent evidence supported knowledge.
  • United States v. Olano, 507 U.S. 725 (1993)
    Olano supplies the four-part plain-error framework applied to the unobjected-to “liar” remark. The panel accepted the first two prongs (error, plain) but found no effect on substantial rights and no serious impact on the proceeding’s fairness or integrity.
  • United States v. Cooper, 827 F.2d 991 (4th Cir. 1987) and Lockett v. Ohio, 438 U.S. 586 (1978)
    Cooper supports the proposition that calling defense witnesses “liars” is improper, though not necessarily reversible. Lockett supports the panel’s view that where a witness’s credibility is already thoroughly damaged, a prosecutor’s label may “add[] nothing” of consequence to the jury’s impression—undermining any claim of outcome-determinative prejudice.

2. Evidence preservation, due process, and criminal spoliation instructions

  • California v. Trombetta, 467 U.S. 479 (1984)
    Trombetta is the due-process anchor for lost evidence that is not “apparently exculpatory” where comparable evidence remains available. The district court used Trombetta to deny constitutional relief; on appeal, Martinez-Chavez did not pursue a due-process claim.
  • Arizona v. Youngblood, 488 U.S. 51 (1988) and Illinois v. Fisher, 540 U.S. 544 (2004) (per curiam)
    Youngblood supplies the “bad faith” requirement for due-process claims involving merely “potentially useful” evidence; Fisher reinforces that requirement. Martinez-Chavez expressly conceded no bad faith, positioning his argument as one for a discretionary adverse-inference instruction rather than constitutional suppression/dismissal.
  • United States v. Johnson, 996 F.3d 200 (4th Cir. 2021)
    Johnson is the centerpiece for the spoliation-instruction argument: it states that “[e]ven absent a due process violation,” a defendant may obtain an adverse-inference instruction upon a showing that the party knew the evidence was relevant and that willful conduct caused its loss. The panel, however, questioned whether Johnson’s discussion is binding, noting Johnson “expressly declined” to decide whether refusal to give such an instruction was error and offered the framework as contingent remand guidance. Even so, the panel applied Johnson’s standard and found both elements unsatisfied.
  • Vodusek v. Bayliner Marine Corp., 71 F.3d 148 (4th Cir. 1995)
    Vodusek supplies the quoted civil-spoliation articulation (knowledge of relevance + willful loss). The panel highlighted a structural tension: in civil cases involving electronically stored information, Fed. R. Civ. P. 37(e)(2) now generally requires “intent to deprive” before an adverse-inference instruction—suggesting that importing Vodusek’s willfulness standard into criminal cases can be “an odd transplant,” especially where due process itself requires bad faith for potentially useful evidence.
  • Payne v. Taslimi, 998 F.3d 648 (4th Cir. 2021)
    Payne supplies the definition of dictum—language that could be removed without impairing the holding—supporting the panel’s caution about treating Johnson’s spoliation-instruction discussion as binding precedent.
  • United States v. Raza, 876 F.3d 604 (4th Cir. 2017)
    Raza supplies the standard for reversible instructional error: the requested instruction must be correct, not substantially covered, and so important that refusal seriously impaired the defense. The panel’s ultimate holding was that denial was within discretion because the Johnson predicates (knowledge and willfulness) were not shown.
  • United States v. Silva, 745 F.2d 840 (4th Cir. 1984) and Campbell v. United States, 365 U.S. 85 (1961)
    These cases support the panel’s rejection of the Jencks Act reframing: the Jencks Act reaches only material “in the possession of the United States,” and Martinez-Chavez did not show the United States possessed the local department’s dispatch recordings.
  • United States v. Diaz, 865 F.3d 168 (4th Cir. 2017)
    Diaz supports bypassing preservation disputes where the argument fails on the merits even if considered.

B. Legal Reasoning

1. Closing argument errors: impropriety conceded, prejudice not shown

The panel treated the two remarks under different standards of review because only one was preserved by objection.

  • Law-enforcement/community-protection appeal (preserved objection): harmless error
    The court accepted that it was improper to urge conviction because the case was “important” to law enforcement and to removing “armed felons” from the streets. But it held the error harmless given: (i) limited tendency to mislead, (ii) the remark’s isolation, (iii) strong curative instructions that officer testimony is neither entitled to more weight nor less and that argument is not evidence, and (iv) overwhelming evidence of knowledge and possession.
  • Calling the defense witness a “liar” (no objection): plain error
    Although the court recognized (consistent with its prior case law) that such labeling is improper, it found no effect on substantial rights because the witness’s credibility had already collapsed through contradictions, rebuttal testimony, and even defense counsel’s own scathing characterization. The label did not plausibly change the verdict.

2. Adverse inference for deleted dispatch recordings: Johnson not satisfied

The dispatch audio was deleted automatically after six months under the sheriff’s department retention policy. The defense requested the “radio runs” only months later, after deletion occurred.

Applying (without definitively endorsing as binding) Johnson’s spoliation-instruction test, the court held:

  1. No showing of government knowledge of relevance before deletion
    The May 1 discovery letter was generic and did not identify the recordings. Johnson requires evidence that the government knew the evidence mattered to a trial issue while it still existed—not merely that it later might have been relevant in hindsight. The panel contrasted Johnson itself, where an investigator knew the deceased victim’s phone contained evidence relevant to a disputed causation issue.
  2. No willful loss
    Automatic deletion under a neutral retention policy, absent evidence that anyone selected the recordings for destruction or deliberately allowed their destruction in the face of a preservation duty, does not constitute “willful conduct” under Johnson. The record instead showed prompt efforts to obtain the recordings once specifically requested.

The court also rejected the attempt to bootstrap willfulness/knowledge from the Jencks Act, reasoning that (i) Jencks applies only to material in the “possession of the United States,” (ii) Jencks is not coextensive with “relevance” as used in Johnson, and (iii) Jencks applicability assessed later does not prove contemporaneous knowledge before deletion.

C. Impact

1. Evidence-retention realities and criminal spoliation instructions

The opinion meaningfully tightens the practical availability of adverse-inference instructions in the Fourth Circuit where evidence is lost through routine, automated retention policies. Even defendants who concede no bad faith (foreclosing Youngblood due-process relief) must still show, at minimum, that the government had contemporaneous knowledge of relevance and engaged in willful conduct leading to loss—requirements that will often be difficult to meet when recordings are purged by default and only later requested.

2. Prosecutorial closing arguments: continued enforcement, limited remedies absent prejudice

The court reaffirmed that “community protection” appeals and direct epithets like “liar” remain improper, but also reinforced a consistent appellate posture: where evidence is overwhelming and the district court gives standard “arguments are not evidence” and “police testimony is not entitled to special weight” instructions, reversal is unlikely.

3. Open question: whether Johnson’s spoliation-instruction framework is binding

By expressly flagging the possibility that Johnson’s spoliation-instruction discussion is dictum, the panel leaves room for future litigants to contest Johnson’s precedential force. Still, the practical guidance is clear: even if Johnson governs, automatic deletion + late request will usually fail the “knowledge” and “willfulness” prongs.

IV. Complex Concepts Simplified

  • Harmless error (Fed. R. Crim. P. 52(a)): Even if the prosecutor did something wrong, the conviction stands if the appellate court concludes the mistake did not affect the verdict in a meaningful way.
  • Plain error (United States v. Olano): If the defense did not object at trial, reversal is harder; the defendant must show a clear legal error that likely affected the outcome and seriously undermined the fairness or legitimacy of the proceeding.
  • Adverse inference instruction: A jury instruction allowing (not requiring) jurors to infer that missing evidence would have been unfavorable to the party responsible for its loss.
  • Spoliation: Loss or destruction of evidence. In this opinion, routine automatic deletion is treated differently from deliberate destruction.
  • “Apparently exculpatory” vs. “potentially useful” evidence (Trombetta/Youngblood): If evidence clearly appears to help the defendant and is destroyed, due process concerns are stronger. If it might have helped but that is uncertain, the defendant generally must show bad faith to obtain constitutional relief.
  • Jencks Act (18 U.S.C. § 3500): A rule requiring the government to produce certain prior statements of its witnesses after they testify. The court emphasized that it applies only to statements in the “possession of the United States,” and it does not automatically establish spoliation-style knowledge or willfulness.

V. Conclusion

United States v. Isaac Martinez-Chavez confirms two core points of Fourth Circuit criminal practice. First, improper closing argument—though condemned—will not warrant reversal absent a concrete showing of prejudice, particularly where instructions and overwhelming evidence support the verdict. Second, and more notably, the court held that the loss of dispatch recordings through automatic deletion under a neutral retention policy, coupled with a late, specific defense request, does not justify a criminal spoliation adverse-inference instruction where the defendant cannot prove contemporaneous government knowledge of relevance and willful conduct causing the loss—even assuming the Johnson framework applies.