Rule 16’s 2022 Expert-Disclosure Deadline Does Not Mandate Exclusion; Continuance Remains the Presumptive Remedy Absent Bad Faith and Substantial Prejudice

Case: United States v. Aryeetey (2d Cir. Mar. 3, 2026)  |  Court: U.S. Court of Appeals for the Second Circuit  |  Panel: Cabranes, Nardini, and Kahn, JJ.

1. Introduction

United States v. Aryeetey presented the Second Circuit with two recurring issues in federal criminal practice: (i) how district courts should respond when the government misses a court-ordered deadline for expert disclosures—here, late-disclosed DNA evidence—and (ii) how deferential appellate review of substantive reasonableness applies to a below-Guidelines prison sentence for a felon-in-possession conviction.

The defendant, Ivanjoel Aryeetey, was tried in the Southern District of New York for possessing a firearm after a felony conviction, in violation of 18 U.S.C. § 922(g)(1). The government’s proof included eyewitness testimony that Aryeetey threw a dark green bag over a fence during flight; police recovered that bag from a construction lot across from a school and found a loaded 9mm Taurus firearm with a defaced serial number inside. A technician had swabbed the firearm for DNA on the day of the incident, but the government obtained Aryeetey’s reference DNA and produced an OCME report only after the district court’s expert-disclosure deadline had passed.

On appeal, Aryeetey argued that the 2022 amendment to Rule 16’s expert-disclosure provisions strengthened enforceable deadlines such that exclusion should follow from the government’s violation, and that a continuance was an inadequate remedy. He also argued that his 78-month sentence—already below the agreed Guidelines range of 110 to 137 months—was substantively unreasonable given his alleged brief possession of the firearm.

2. Summary of the Opinion

The Second Circuit affirmed in full. It held that the 2022 amendment to Federal Rule of Criminal Procedure 16(a)(1)(G)(ii)—requiring courts to set expert-disclosure deadlines “sufficiently before trial”— did not curtail a district court’s longstanding discretion under Rule 16(d)(2) to select an appropriate remedy for noncompliance. Exclusion remains “a drastic remedy” generally reserved for circumstances such as bad faith or substantial prejudice.

Applying that framework, the court agreed the government was negligent but found no bad faith and no substantial prejudice to the defense. The district court’s offer of a significant continuance (which Aryeetey declined in favor of a one-day delay) was within its remedial discretion. The court also found the 78-month sentence comfortably within the range of permissible decisions, given the dangerous conduct during flight, the loaded gun with a defaced serial number, the proximity to a school, and Aryeetey’s history of unlawful firearm possession.

3. Analysis

3.1 Precedents Cited

The opinion is principally a synthesis of Second Circuit Rule 16 remedy doctrine with the 2022 amendment’s emphasis on enforceable timelines. The court drew on prior cases to reaffirm two propositions: (1) district courts have “broad discretion” to fashion discovery remedies, and (2) reversal requires “substantial prejudice,” meaning a concrete impact on trial strategy, not merely harmful evidence.

  • United States v. Miller, 116 F.3d 641 (2d Cir. 1997)
    Cited for the foundational statement that, when the government fails to comply with Rule 16, the district court has “broad discretion” to decide what remedial action is appropriate, including accommodating late disclosures with a continuance.

    Aryeetey relies on Miller to anchor its reading that remedial discretion comes directly from Rule 16(d)(2), which the 2022 amendment did not change. The court also invoked Miller for the pragmatic point that offering to “entertain a request for a continuance” is often an adequate solution where the timing problem is curable.

  • United States v. Walker, 974 F.3d 193 (2d Cir. 2020)

    Walker provided the most analogous template: incriminating evidence disclosed shortly before trial, the district court offers a “lengthy continuance,” and the defendant declines. The Second Circuit in Aryeetey used Walker to reject the argument that a continuance is inherently inadequate because it burdens the defendant’s liberty interests (e.g., remaining detained pretrial) or could help the government prepare.

  • United States v. Wynder, 147 F.4th 200 (2d Cir. 2025)

    Wynder contributed two key standards: (1) “preclusion” is “a drastic remedy” disfavored when nondisclosure is not in bad faith, and (2) reversal requires a showing that nondisclosure resulted in “substantial prejudice.” Aryeetey adopts both propositions as controlling and applies them to DNA evidence disclosed after the court-ordered expert deadline but before trial.

  • United States v. Eby, No. 24-3716, 2025 WL 3688925 (6th Cir. Dec. 19, 2025)

    The court cited Eby as persuasive authority consistent with its approach: admitting belatedly disclosed material is not an abuse of discretion absent a concrete showing of prejudice. While from the Sixth Circuit, the citation underscores Aryeetey’s position that the 2022 amendment does not create a near-automatic exclusion rule.

  • United States v. Felder, 993 F.3d 57 (2d Cir. 2021)

    Felder reinforced that even mid-trial disclosure of expert intent can be cured by a continuance and need not trigger exclusion. Aryeetey uses it to show that, where the remedy of additional preparation time is feasible, appellate courts defer to district courts choosing that remedy over preclusion.

  • United States v. Canada, 858 F. App’x 436 (2d Cir. 2021) (summary order)

    Cited for the proposition that late expert disclosure may be excused where the government notifies the defense promptly upon learning the information is available, and where bad faith is absent. Aryeetey uses Canada to contextualize that the timing of discovery is often driven by practical contingencies and that the remedy question turns on prejudice and intent, not simply tardiness.

  • United States v. Sanchez, 912 F.2d 18 (2d Cir. 1990)

    Sanchez supplied the “substantial prejudice” trigger for reversal. Aryeetey ties modern Rule 16 remedy doctrine to this older appellate standard: even if a district court could have sanctioned more harshly, reversal is not warranted unless the defendant can show substantial prejudice.

  • United States v. Lee, 834 F.3d 145 (2d Cir. 2016)

    Lee defines “substantial prejudice” in operational terms: it is not enough that the evidence is damaging; the defendant must show the late disclosure “adversely affected some aspect of his trial strategy.” This definition does the decisive work in Aryeetey: because Aryeetey did not show impaired strategy (and asked for only a one-day continuance), he could not satisfy the prejudice standard.

  • United States v. Ulbricht, 858 F.3d 71 (2d Cir. 2017), overruled on other grounds by Carpenter v. United States, 585 U.S. 296 (2018)

    Ulbricht functions as a contrast case. There, substantial prejudice existed because the opposing party was about to rest, had “no time” to prepare to respond, and a continuance risked losing jurors. Aryeetey distinguishes that high-prejudice scenario from a late disclosure made before trial where the court offered meaningful continuance options and the defendant did not demonstrate lack of time to respond.

    The reference to Carpenter v. United States is limited to noting that Ulbricht was overruled “on other grounds,” preserving Ulbricht’s relevance on trial-prejudice principles while acknowledging later Fourth Amendment developments.

On sentencing, the opinion sits squarely within the Second Circuit’s deferential substantive-reasonableness line.

  • United States v. Muzio, 966 F.3d 61 (2d Cir. 2020)

    Supplies the “particularly deferential” standard and the formulation that only sentences “shockingly high” or otherwise unsupportable warrant reversal. Aryeetey uses Muzio to frame review as exceptional, not routine.

  • United States v. Broxmeyer, 699 F.3d 265 (2d Cir. 2012)

    Reiterates that the weight assigned to aggravating and mitigating factors is committed to the sentencing judge’s discretion. Aryeetey relies on this to reject the defendant’s invitation to reweigh “brief possession” against public-safety and deterrence considerations.

  • United States v. Cavera, 550 F.3d 180 (2d Cir. 2008) (en banc)

    Provides the governing test: reversal only when the sentence cannot be located within the range of permissible decisions, and appellate review considers the “totality of the circumstances.” Aryeetey leans on Cavera to uphold a sentence meaningfully below the Guidelines based on the district court’s articulated assessment of risk, context, and history.

  • United States v. Rivera, 115 F.4th 141 (2d Cir. 2024)

    Used for the commonplace but important point: mere disagreement with how the district court weighed the 18 U.S.C. § 3553(a) factors does not make a sentence substantively unreasonable.

  • United States v. Ingram, 721 F.3d 35 (2d Cir. 2013)

    Quoted for the observation that “the overwhelming majority of cases” fall within the broad range of reasonable sentences, particularly when the Guidelines were properly calculated and considered. Aryeetey uses Ingram to underscore that this case is not an outlier.

  • United States v. Perez-Frias, 636 F.3d 39 (2d Cir. 2011)

    Cited for the practical appellate reality: it is “difficult” to find a below-Guidelines sentence unreasonable. This buttresses the holding that a 78-month term, well below 110–137 months, is unlikely to satisfy the “shock the conscience” threshold.

3.2 Legal Reasoning

A. The 2022 Rule 16 amendment strengthens deadlines but not the exclusion remedy

Aryeetey’s core interpretive argument was that the addition of Rule 16(a)(1)(G)(ii)—requiring courts to set a disclosure time “sufficiently before trial” to provide a fair opportunity to meet expert evidence—should be read to demand stricter enforcement, namely exclusion, when the government misses that deadline.

The Second Circuit rejected that reading on textual and structural grounds:

  • No fixed timeframe in the amendment. The advisory committee notes emphasize that the amendment “does not itself set a specific time” and instead allows courts to “tailor” deadlines to local conditions and case-specific realities. That tailoring premise is inconsistent with a rigid, automatic sanction.
  • Remedial authority remains in Rule 16(d)(2), unchanged. The court emphasized that Rule 16(d)(2) expressly lists a menu of remedies (ordering discovery, granting a continuance, excluding the evidence, or “any other order that is just”). Because the amendment did not alter this provision, it did not implicitly remove the district court’s choice among remedies.
  • Continuances remain a central tool. The court treated continuances as a standard, often sufficient cure for late disclosure where the defense can still prepare and cross-examine effectively.

B. Exclusion is “drastic” and typically requires bad faith or substantial prejudice

Building on United States v. Wynder, the court reiterated that preclusion is disfavored absent bad faith. Here, the district court found the government negligent and criticized it for waiting until after the deadline to begin DNA testing, but did not find bad faith. That finding mattered because the Second Circuit’s Rule 16 cases generally reserve exclusion for willful misconduct or situations where the harm to fairness cannot be cured.

C. “Substantial prejudice” requires a concrete effect on trial strategy

The most consequential step in the court’s analysis was the application of the prejudice standard from United States v. Lee. The panel stressed that “substantial prejudice” is not established merely because the evidence is powerful. A defendant must show that late disclosure changed or impaired the defense’s trial strategy in a meaningful way (for example, by foreclosing an expert consultation, preventing investigation, or forcing unplanned concessions).

In Aryeetey, several facts undercut the prejudice claim:

  • Aryeetey had notice for weeks that DNA testing was underway and that the government would likely use favorable results.
  • Aryeetey previously filed a motion in limine seeking to admit anticipated DNA evidence (expecting it might be exculpatory), which reduced the claim of unfair surprise.
  • The district court offered continuances of 21 or 42 days (and a willingness to find other dates), but Aryeetey chose to proceed with only a one-day delay and represented that he could “effectively address” the DNA witness in a short time.

The panel acknowledged the defendant’s practical dilemma—continuances can prolong pretrial detention and may give the government additional preparation time—but held that, under Second Circuit standards, those burdens do not equate to “substantial prejudice” unless tied to demonstrable impairment of the defense at trial.

D. Substantive reasonableness: deferential review and a record-based justification

On sentencing, the court applied the deferential framework of United States v. Muzio and United States v. Cavera. It focused on the district court’s reasons: dangerous flight in a busy area, the loaded firearm with a defaced serial number, disposal across from a school, and recidivist firearm conduct while on supervised release.

Aryeetey’s “brief possession” argument did not carry the day because the sentencing judge considered it and still found the overall conduct serious and the need for deterrence substantial. Under United States v. Broxmeyer and United States v. Rivera, appellate courts do not reweigh these considerations so long as the sentence remains within the permissible range. The below-Guidelines nature of the sentence further reinforced affirmance under United States v. Perez-Frias.

3.3 Impact

A. Rule 16 after the 2022 amendment: enforceable deadlines, flexible remedies

The decision’s principal doctrinal contribution is clarifying how the Second Circuit will read the 2022 amendment’s “set a time” requirement:

  • The amendment is not an exclusion mandate. Missing a court-set expert-disclosure deadline does not create a presumption of preclusion.
  • Rule 16(d)(2) remains the remedial center of gravity. District courts retain broad discretion to tailor remedies to the circumstances, with continuances as an ordinary cure and exclusion as a last resort.
  • Appellate review will remain prejudice-focused. Defendants seeking reversal must show a strategy-level harm, consistent with Lee and Wynder.

B. Practical consequences for litigants

  • For defendants: To maximize a Rule 16 challenge on appeal, the record should concretely identify what could not be done because of the late disclosure (e.g., inability to retain a rebuttal expert, lost investigation opportunities, altered opening/closing theory, or cross-examination constraints), and why a continuance would not cure that harm.
  • For the government: The opinion contains a clear admonition that negotiations and resource allocation do not justify ignoring court orders; if testing will not be completed, the government should seek an extension rather than allow deadlines to lapse.
  • For district courts: The decision supports robust case-management: courts may criticize negligent conduct, offer meaningful continuances, and still admit evidence where fairness can be preserved—without fearing that the 2022 amendment requires categorical exclusion.

C. Sentencing: brief possession is a factor, not a rule

The sentencing portion reinforces that “brief” possession of a firearm is not a categorical mitigator. It is one of many § 3553(a) considerations, and district courts may permissibly give greater weight to context (dangerous flight, loaded weapon, defaced serial number, proximity to a school, and recidivism), particularly where the ultimate term is below the Guidelines.

4. Complex Concepts Simplified

  • Rule 16(a)(1)(G) (expert disclosures): Requires the government to provide a written description of expert testimony it intends to use at trial (including opinions, bases, reasons, and qualifications). The 2022 amendment added that the court must set the disclosure time and that it must be early enough to give the other side a fair chance to respond.
  • Rule 16(d)(2) (remedies/sanctions): If a party violates discovery obligations, the court may order the missing discovery, grant a continuance, exclude the evidence, or craft any other just remedy. This is the source of the district court’s “broad discretion.”
  • Preclusion / exclusion: A sanction barring the late-disclosed evidence from trial. The Second Circuit describes it as “drastic” because it can prevent the jury from hearing probative evidence and can function like a case-determinative penalty.
  • Bad faith vs. negligence: Negligence is careless or unjustified delay; bad faith implies intentional misconduct or strategic concealment. The court treats bad faith as a strong reason to consider harsher sanctions like exclusion.
  • “Substantial prejudice” (in Rule 16 appeals): Not simply that the evidence hurt the defense, but that the late timing impaired the defense’s ability to prepare or forced a meaningful change in trial strategy (for example, losing the opportunity to consult an expert or investigate).
  • Substantive reasonableness: Appellate review asking whether the length of the sentence is so extreme that it falls outside the “range of permissible decisions,” considering the totality of circumstances and the district court’s reasons.
  • Guidelines range and below-Guidelines sentence: The Sentencing Guidelines produce an advisory imprisonment range. A sentence below that range is often harder (though not impossible) to overturn as substantively unreasonable on appeal.

5. Conclusion

United States v. Aryeetey cements a clear Second Circuit message about Rule 16 after the 2022 amendment: while expert-disclosure deadlines are meant to be enforceable and set early enough to ensure fairness, the amendment does not convert missed deadlines into a near-automatic exclusion rule. District courts retain broad authority under Rule 16(d)(2) to choose proportionate remedies—especially continuances—so long as the defendant is not substantially prejudiced in a way that affects trial strategy.

On sentencing, the decision reiterates highly deferential substantive-reasonableness review and confirms that “brief possession” arguments will rarely overcome a well-explained, below-Guidelines sentence grounded in public-safety risk, deterrence, and recidivism concerns.