United States v. Nieves-Diaz

Summary

Heclouis Joel Nieves-Diaz pleaded guilty to felon-in-possession of ammunition, possession of a machine gun conversion device, and possession with intent to distribute cocaine. At his first sentencing the district court imposed an 84-month sentence with a four-level enhancement under U.S.S.G. § 2K2.1(b)(6)(B); the First Circuit (Nieves I) vacated because the ammunition was not shown to have facilitated a drug-trafficking offense. On remand, the district court resentenced him to 66 months — 25 months above the top of the new 33-41 month Guidelines range — citing his criminal history, the 149 rounds of .223 ammunition, and the gun-crime rate in Puerto Rico. The First Circuit vacated again for procedural error. The court did not identify why the ammunition quantity was aggravating when Nieves did not possess a corresponding firearm — a novel wrinkle in First Circuit ammunition-variance case law. The panel affirmed that the district court could consider Nieves's prior record and swift recidivism on remand, declined to cap the sentence or reassign the judge, and remanded for a third sentencing.

Structured facts

Parties

Petitioner/Appellant: Heclouis Joel Nieves-Diaz (defendant-appellant)
Respondent/Appellee: United States

Jurisdiction

federal — First Circuit on appeal from the District of Puerto Rico

Statutes cited

18 U.S.C. §§ 922(g)(1), 922(o), 924(a)(2), 18 U.S.C. § 841(a)(1), (b)(1)(C), U.S.S.G. § 2K2.1(b)(6)(B) [now (b)(7)(B)]

Issue

Whether the district court adequately explained its upward variance where the primary aggravating factor was a substantial quantity of ammunition possessed without any corresponding firearm.

Holding

No. The court must clearly identify why ammunition amount is aggravating and respond to the defendant's dominant argument (no firearm, no danger); without that, the variance cannot be reviewed for reasonableness.

Outcome

vacated and remanded

Vote

unanimous panel (Barron, Thompson, Aframe)

Majority author

Judge Aframe

Key facts

• Police executing a search warrant at Nieves's apartment found 149 rounds of .223 ammunition, 849 cocaine baggies, and a machine gun conversion device.
• Nieves was on supervised release (twice revoked) from a prior drug-trafficking conspiracy conviction.
• At first sentencing, court applied § 2K2.1(b)(6)(B) and varied upward to 84 months; Nieves I vacated.
• On remand, court sentenced him to 66 months — 25 months above the 33-41 month range — citing criminal history, 149 rounds, and community gun-violence.
• Nieves argued the ammunition quantity could not justify the variance because he did not possess a corresponding firearm.

Reasoning

Procedural reasonableness requires sufficient explanation for any deviation from the Guidelines (Pupo, Díaz-Rivera). Prior cases approving ammunition-based variances had corresponding firearms (García-Mojica, Contreras-Delgado). Because Nieves's case is novel — ammunition without a firearm — the district court had to explain whether potential danger, sheer quantity, or other case-specific features removed the case from the heartland. Failure to engage with Nieves's 'dominant argument' (Colón-Cordero) was procedural error. The panel simplified remand by affirming that prior record and speed of recidivism could support a variance (Fargas-Reyes, Polaco-Hance), declined to cap the sentence or reassign the judge, and remanded.

Implications

The decision sharpens First Circuit procedural-reasonableness review in two ways. First, it creates an unresolved question — still open on remand — about whether ammunition quantity alone, absent a compatible firearm, can support an upward variance; the court refused to foreclose that possibility but required case-specific reasoning. Second, it reinforces the Colón-Cordero rule that a sentencing court must engage with the defendant's 'dominant' argument, not merely list aggravating factors. Districts should expect more remands where variance justifications do not line up with the defense theory. Practically, defense counsel now has a clear template for challenging ammunition-based upward variances in non-firearm felon cases.

Related cases

• United States v. Nieves-Diaz (Nieves I), 99 F.4th 1 (1st Cir. 2024) — prior appeal
• United States v. Polaco-Hance, 103 F.4th 95 (1st Cir. 2024) — ammunition-based variance
• United States v. Gonzalez-Flores, 988 F.3d 100 (1st Cir. 2021) — ammunition as variance consideration
• United States v. Mercado-Cañizares, 133 F.4th 173 (1st Cir. 2025) — identifying ammunition-quantity rationale
• United States v. Colón-Cordero, 91 F.4th 41 (1st Cir. 2024) — engagement with dominant argument
• United States v. Fargas-Reyes, 125 F.4th 264 (1st Cir. 2025) — recidivism-based variance

Practical guide

For federal defense counsel in Puerto Rico firearm/ammunition cases: (1) raise a focused 'dominant argument' about the specific aggravating factor — e.g., why ammunition alone isn't dangerous without a compatible firearm — and insist on record-level engagement by the court; (2) object to community-factor reliance if not paired with individualized reasoning (Polaco-Hance / Zapata-Vázquez). For AUSAs: when pressing ammunition-quantity variances, develop the record on dangerousness (caliber, compatibility with nearby firearms, usable magazines) so the district court can explain it. For district judges: if varying upward on an ammunition ground, state whether the driver is dangerousness, sheer quantity, or a specific case feature — a recital of precedents is not enough. For Puerto Rico compliance/firearms attorneys: Nieves II confirms that even without a corresponding firearm, large ammunition caches can still figure in sentencing; the issue is how the court explains itself.

FAQ