Similarity for Rule 404(b) May Rest on a Ballistics Identity Link; Limits on Bias Cross Concerning State Charges; Defendant‑Caused Delays Narrow Barker Clock — United States v. Stuart (5th Cir. 2025)

Court: United States Court of Appeals for the Fifth Circuit

Panel: Judges Smith, Clement, and Duncan (opinion by Judge Jerry E. Smith)

Date: March 28, 2025

Docket No.: 23-20590

Introduction

United States v. Stuart is a comprehensive Fifth Circuit decision addressing four recurring trial and appellate issues in federal criminal practice: (1) the admissibility of “other acts” evidence under Federal Rule of Evidence 404(b) when identity is the central issue and the same firearm links the events; (2) whether brief opening references to a later-severed count require reversal; (3) the scope of Confrontation Clause cross-examination into a government witness’s pending state charges to show bias; and (4) the Sixth Amendment speedy trial analysis when substantial delay is defendant-caused.

The case arose from two armed robberies of Houston gas stations on May 18 and May 23, 2019, charged as Hobbs Act robberies with corresponding § 924(c) counts. During pretrial detention in 2020, the defendant, Hezron Benjamin Stuart, also allegedly assaulted a prison officer, leading to a separate indictment. Shortly before trial in March 2023, the indictments were consolidated; part-way through trial, the district court severed the prison-assault charge as unduly prejudicial and proceeded only on the robbery and firearm counts.

At trial, identity was hotly contested. The government used ballistic evidence to show the same gun was fired during a May 7 domestic incident and later in the May 18 and 23 robberies. Over objection, the court admitted detailed testimony about the May 7 incident under Rule 404(b) for identity (and, initially, intent/state of mind), with limiting instructions. The jury heard from both robbery victims; one witness, Abdul Kareem, was testifying while in state custody. The court allowed general bias cross-examination but barred inquiry into the specifics of Kareem’s pending state charges. The jury convicted on the robbery and firearm counts, and the district court later severed the prison-assault count before any evidence was admitted on it.

On appeal, Stuart challenged: (A) the Rule 404(b) ruling; (B) the government’s and court’s opening references to the (later-severed) prison assault; (C) cross-examination limits under the Confrontation Clause; and (D) the denial of his speedy trial claim. The Fifth Circuit affirmed.

Summary of the Opinion

Rule 404(b) — Identity via Ballistic Link: The court held it was not an abuse of discretion to admit testimony about the May 7 domestic incident linking the same gun to the charged robberies. Under United States v. Beechum, “similarity” is assessed in relation to the issue the evidence addresses; here, identity. The shared firearm, coupled with contested identity and limiting instructions, made the evidence probative and not unduly prejudicial under Rule 403.
Opening References to a Later-Severed Count: Even assuming error in mentioning the prison-assault charge during openings (reviewed for plain error), any error was harmless. No evidence was introduced on the assault, the court severed the count, and the jury received curative instructions. Stuart also affirmatively agreed to the severance instruction, waiving any challenge to it.
Confrontation Clause — Limits on Bias Cross: The district court permissibly barred cross-examination into the specific nature of Abdul Kareem’s pending state charges. While bias cross is generally allowed, the specifics were only marginally relevant (the jury already knew he was a jailed felony arrestee, and his charges were brought by the state, not the federal government) and substantially outweighed by prejudice under Rule 403. No Sixth Amendment violation occurred.
Speedy Trial: Applying Barker v. Wingo, the court attributed roughly two years of delay to Stuart’s own continuances and litigation choices (including refusal to undergo a § 4241 evaluation), leaving only about 18 months of delay to weigh at all. That span did not strongly favor Stuart; he belatedly asserted the right; and he failed to show actual prejudice (and forfeited that argument by raising it only in reply). No speedy trial violation occurred.

Analysis

Precedents Cited and Their Influence

United States v. Beechum, 582 F.2d 898 (5th Cir. 1978) (en banc): Established the Fifth Circuit’s two-step framework for Rule 404(b): (1) other-act evidence must be relevant to a non-character issue; (2) its probative value must not be substantially outweighed by undue prejudice under Rule 403. It also requires sufficient proof the defendant committed the extrinsic act. Stuart applies Beechum’s “similarity is determined by the issue” principle to identity via a shared firearm, confirming that similarity need not be by modus operandi when the identity issue is advanced by a ballistics link.
United States v. Meyer, 63 F.4th 1024 (5th Cir.), cert. denied, 144 S. Ct. 312 (2023): Reiterates 403 considerations for extrinsic-act evidence: government’s need, similarity, temporal proximity, limiting instructions, and overall prejudice. Stuart leans on Meyer to uphold admission, noting the government’s need to prove identity (hotly contested), the closeness in time (May 7 to May 18/23), and strong limiting instructions; it also notes that dissimilarity in modus operandi actually reduced unfair prejudice.
United States v. Peterson, 244 F.3d 385 (5th Cir. 2001): Sets the abuse-of-discretion standard for evidentiary rulings, with review “necessarily heightened in criminal cases.” Stuart applies that standard to sustain the 404(b) ruling.
United States v. Pittsinger, 874 F.3d 446 (5th Cir. 2017): States the three elements of plain-error review for unpreserved claims: error, plainness, and effect on substantial rights. Stuart uses this to frame the opening-statement issue.
United States v. Munoz, 150 F.3d 401 (5th Cir. 1998): Demonstrates that even potentially improper disclosures can be cured by the absence of further references and strong instructions. Stuart follows Munoz to reject reversal based on brief opening references to the severed count.
United States v. Lowenberg, 853 F.2d 295 (5th Cir. 1988) and United States v. Chase, 838 F.2d 743 (5th Cir. 1988): Prosecutorial remarks warrant reversal only if both inappropriate and harmful. Stuart applies this “inappropriate and harmful” pairing to the brief mention of the assault count.
Old Chief v. United States, 519 U.S. 172 (1997): Cited in Munoz; discussed in Stuart to illustrate that curative measures can neutralize prejudice from references to prior bad acts or convictions.
United States v. Nieto, 721 F.3d 357 (5th Cir. 2013) and United States v. Owens, 683 F.3d 93 (5th Cir. 2012): Jurors are presumed to follow limiting and curative instructions. Stuart repeatedly invokes this presumption to sustain both the 404(b) and severance cures.
United States v. Hill, 63 F.4th 335 (5th Cir.), cert. denied, 144 S. Ct. 207 (2023): A defendant waives an instruction challenge by affirmatively agreeing to the instruction. Stuart applies Hill to hold that agreeing to the severance instruction forecloses complaint about its wording.
Delaware v. Fensterer, 474 U.S. 15 (1985): The Confrontation Clause assures an “opportunity for effective cross,” not cross “effective in whatever way” the defense wishes. Stuart relies on this to uphold reasonable limits on cross into a witness’s pending state charges.
United States v. Skelton, 514 F.3d 433 (5th Cir. 2008): Provides the “significantly different impression of credibility” test for Confrontation claims; clarifies that non-608 bias evidence remains subject to Rule 403. Stuart uses Skelton to conclude the specifics of state charges were marginally probative of bias and substantially outweighed by prejudice.
United States v. Holdman, 75 F.4th 514 (5th Cir. 2023): The court of appeals may affirm on any ground supported by the record. Stuart uses this to resolve the Confrontation issue under Rule 403 even if Rule 608(b) might not bar the inquiry.
Barker v. Wingo, 407 U.S. 514 (1972): The four-factor speedy trial test. Stuart applies Barker’s length, reasons, assertion, and prejudice framework, emphasizing defendant-caused delays.
Nelson v. Hargett, 989 F.2d 847 (5th Cir. 1993): Explains the “threshold” nature of delay, 1-year trigger, and that defendant-caused delays are excluded from Barker’s length calculation. Stuart follows Nelson to narrow the countable delay to ~18 months.
Amos v. Thornton, 646 F.3d 199 (5th Cir. 2011) (per curiam): Delays must exceed roughly 30 months total (about 18 months beyond the 1-year threshold) to strongly favor the accused. Stuart treats the attributable ~18 months as not strongly favoring the defendant.
United States v. Serna-Villarreal, 352 F.3d 225 (5th Cir. 2003): Even 3 years and 9 months may not weigh heavily for the defendant. Stuart cites this to contextualize the length factor.
United States v. Davis, 61 F.3d 291 (5th Cir. 1995) and United States v. Soto, 734 F. App’x 258 (5th Cir. 2018) (per curiam): Uphold district court discretion to order § 4241 competency evaluations when there is reasonable cause, citing factors like history of irrational behavior and counsel’s concerns. Stuart applies these to justify evaluation-related delays.
United States v. Duran-Gomez, 984 F.3d 366 (5th Cir. 2020): Prejudice is presumed only when the first three Barker factors weigh heavily against the government; otherwise actual prejudice must be shown. Stuart uses this to reject presumed prejudice and notes the defense forfeited any actual-prejudice showing by raising it only in reply.
United States v. Jackson, 426 F.3d 301 (5th Cir. 2005) (per curiam): Arguments raised for the first time in a reply brief are forfeited. Applied in Stuart to the speedy-trial prejudice claim.

Legal Reasoning

A. Rule 404(b) Admission of the May 7 Domestic Incident to Prove Identity

The court applied the Beechum two-step analysis:

Step 1 — Relevance to a Non-Character Issue: The government’s theory was identity. It tied a May 7 domestic assault to the robberies using ballistics: a casing recovered from the May 7 scene matched the gun used in the May 18 and May 23 robberies. Because “similarity” under Beechum is assessed in relation to the issue the extrinsic act addresses, the court held the shared firearm made the May 7 evidence relevant to identity even though the domestic dispute did not share a robbery modus operandi.
Proof Defendant Committed the Extrinsic Act: Relevance depended on showing Stuart committed the May 7 act. Once the defense questioned that premise in opening (challenging how the casing was tied to him), the government had “need” to call witnesses (the victim and responding officer) to prove he committed the May 7 assault. This satisfied Beechum’s requirement that the extrinsic act be established.
Step 2 — Rule 403 Balancing: Several factors favored admission:
- Government’s need was strong: identity was the central contested issue; the defense disputed eyewitness identifications and surveillance video.
- Temporal proximity: the events occurred within days (May 7, 18, 23), increasing probative value.
- Limiting instructions: the district court repeatedly limited the jury’s use of the May 7 evidence, initially to intent/state of mind and ultimately also to identity, and the court presumes juries follow such instructions.
- Overall prejudice was limited: the domestic incident did not closely resemble an armed gas-station robbery, which reduced the risk the jury would substitute propensity reasoning; paradoxically, the lack of MO similarity decreased unfair prejudice in this context.

Bottom line: when identity is the issue, a ballistics link can supply the “similarity” required by Rule 404(b), and the government may introduce detailed testimony to establish the extrinsic act if the defendant contests that he committed it. The district court did not abuse its discretion.

B. Opening References to a Later-Severed Prison Assault Count

Stuart did not object at trial, so review was for plain error. The court did not definitively decide whether joining the 2020 assault count with the 2019 robbery/§ 924(c) counts was error under Rule 8 or whether brief opening references to that count were improper. Instead, it found any error harmless for three reasons:

No evidence on the assault was admitted; the court severed the count mid-trial as too prejudicial and “not at the heart” of the case.
The jury was specifically instructed that it had heard no evidence on the assault and must disregard any mention of it.
Stuart expressly agreed to the wording of the severance instruction, waiving any challenge to its content under Hill.

These factors mirror Munoz, where curative measures restored fairness. The presumption that jurors heed instructions under Nieto/Owens sealed the conclusion that the references were not harmful.

C. Confrontation Clause — Limits on Cross About a Witness’s Pending State Charges

The district court permitted bias cross-examination in general (i.e., whether Kareem expected favorable treatment) but excluded the specifics of his pending state charges (aggravated assault and attempted kidnapping).

Under Skelton, even non-608(b) bias evidence is subject to Rule 403. The Fifth Circuit held the specific nature of the charges was only marginally relevant to bias because:

The jury already knew Kareem was in custody on felony charges (he appeared in an orange jumpsuit), so the core bias point was before the jury.
His charges were brought by the state, reducing any incentive to curry favor with federal prosecutors; the marginal probative value was small in a federal trial.

The court concluded the excluded details would not have produced a “significantly different impression” of credibility for the jury and therefore found no Confrontation Clause violation.

D. Sixth Amendment Speedy Trial

Applying Barker v. Wingo:

Length of delay: Although 45 months elapsed between indictment (August 2019) and trial (March 2023), roughly two years were attributable to defense continuances and related litigation choices. The court thus treated the countable delay as about 18 months—enough to trigger analysis but not to strongly favor the defendant under Amos.
Reasons for delay: The defense bears primary responsibility: multiple continuances; repeated attorney-substitution efforts and filings; refusal to submit to a § 4241 competency evaluation that the court properly ordered given reasonable cause (citing Davis and Soto).
Assertion of the right: Stuart delayed asserting his speedy-trial rights for approximately two years after the superseding indictment, which cut against him.
Prejudice: Not presumed because the first three factors did not weigh heavily against the government (Duran-Gomez). Stuart forfeited any actual prejudice argument by raising it only in reply (Jackson).

Balancing these factors, the court found no violation.

Impact and Significance

Rule 404(b) Identity Proof via Ballistics: Stuart provides a crisp, defense-resistant mode of analysis for prosecutors: when identity is the issue, the “similarity” required by Rule 404(b) may be satisfied by a shared firearm—a forensically grounded link—without a shared modus operandi. Expect more frequent admission of extrinsic acts tied by ballistics, especially with short temporal gaps and when identity is contested. Defense counsel should anticipate that challenging whether the defendant committed the extrinsic act will open the door to detailed testimony proving that act.
Limiting Instructions Matter: The opinion reinforces the practical power of tailored limiting instructions to overcome Rule 403 concerns. Trial judges in the Fifth Circuit can lean on repeated, precise instructions to cabin the jury’s use of 404(b) evidence and cure potential prejudice from opening remarks.
Confrontation Clause and Bias Cross on State Charges: Stuart underscores that the marginal probative value of a witness’s pending state charges to show bias in a federal prosecution is often low, particularly where the jury already knows the witness is in custody. Defense attempts to probe the specifics are likely to face Rule 403 headwinds. To enhance probative value, defense counsel should be prepared to show a concrete federal benefit route (e.g., cooperation agreements affecting related federal exposure or inter-sovereign coordination) rather than relying on the mere fact of state charges.
Severed Counts and Opening References: The decision confirms that brief, early references to a count later severed do not automatically require reversal, especially where no evidence is introduced, and instructions are clear. It also cautions defendants: agreeing to the precise wording of curative instructions can waive later objections.
Speedy Trial — Defendant-Caused Delay: Stuart is a reminder that Barker’s length-of-delay factor may be effectively reduced by subtracting defense-caused delays (continuances, counsel changes, refusal to undergo competency evaluations). Defendants who drive the docket cannot later reap the benefit of those delays. Also, assertions of the right should be timely, and claims of prejudice must be developed and preserved in opening appellate briefs.

Complex Concepts Simplified

Rule 404(b) “Other Acts” Evidence: You generally can’t use prior bad acts to say “he’s the kind of person who would do this.” But you can use them for specific permissible purposes—like proving identity, intent, or absence of mistake. The act must be similar to the issue at hand, and the judge must ensure its value isn’t outweighed by unfair prejudice (Rule 403).
“Similarity” Tailored to the Issue: Similarity is not one-size-fits-all. If the issue is identity, similarity can come from a distinctive link—like the same gun—rather than a copied method of committing the crime.
Rule 403 Balancing: Even relevant evidence can be excluded if its unfair prejudice substantially outweighs its value. Judges weigh need, similarity, timing, and whether instructions can reduce misuse.
Confrontation Clause vs. Evidence Rules: The Sixth Amendment gives the defense a fair chance to cross-examine, especially to show bias. But the court can still limit cross if the details add little probative value and risk unfair prejudice or confusion.
Rule 608(b) and 609: 608(b) generally bars extrinsic evidence of specific past acts to show a witness’s deceitful character; 609 governs using certain convictions to impeach. Bias is a separate, permitted topic—but it still must pass Rule 403.
Misjoinder and Severance: Cases or counts can be joined if they are of the same or similar character or are part of the same scheme. If a joined count would unfairly prejudice the jury, courts can sever it and instruct jurors to disregard it.
Plain Error vs. Harmless Error: If the defense didn’t object at trial, it must show a clear, obvious error that affected substantial rights. Even then, appellate courts often ask whether any error was harmless—i.e., whether it likely affected the outcome.
Waiver vs. Forfeiture: Forfeiture is failing to object; waiver is intentionally giving up a right (for example, by agreeing to an instruction). Waiver usually precludes appellate review.
Barker v. Wingo Speedy Trial Test: Courts weigh four factors: (1) how long the case took to go to trial; (2) why it took that long; (3) whether the defendant asserted the right; and (4) whether the delay prejudiced the defense. Delays the defendant causes don’t count against the government.
Competency Evaluations under 18 U.S.C. § 4241: If there’s reasonable cause to believe the defendant may be incompetent, courts may order an evaluation and hold a competency hearing; refusal to cooperate can legitimately delay the case.

Conclusion

United States v. Stuart meaningfully clarifies three practical doctrines in the Fifth Circuit. First, for Rule 404(b), “similarity” is calibrated to the issue at stake: where identity is disputed, a shared firearm and ballistics match can supply similarity and support admission of detailed extrinsic-act testimony, especially under tight limiting instructions and with close temporal proximity. Second, brief opening references to a later-severed count, without accompanying evidence and followed by curative instructions (particularly those the defendant approves), will rarely warrant reversal. Third, the scope of Confrontation Clause cross to show bias can be reasonably limited when a witness’s pending state charges add little probative value in a federal prosecution and risk substantial prejudice. Finally, the decision underscores that defendant-driven delays narrow the Barker analysis, weaken claims of prejudice, and can defeat speedy trial challenges.

For practitioners, Stuart is both a roadmap and a warning: the government can leverage forensic identity links to admit 404(b) evidence; defendants should anticipate—and plan for—limiting instructions and Rule 403 balancing; bias cross must be targeted and genuinely probative; and docket management choices will count in speedy trial calculus. The opinion thus strengthens the Fifth Circuit’s already well-developed frameworks for 404(b), Confrontation Clause limits, curative instructions, and Barker analysis.