“Reason to Believe” Means a Probable-Cause “Fair Probability”: Sixth Circuit Upholds §2K2.1 Firearms-Trafficking Enhancement for Undercover Sales and Rejects Double Counting

Introduction

In United States v. Elias Pagan, No. 24-4102 (6th Cir. Oct. 16, 2025) (not recommended for publication), the Sixth Circuit affirmed a four-level firearms-trafficking enhancement under U.S.S.G. § 2K2.1(b)(5) (2021) following a guilty plea for drug distribution and unlicensed firearms dealing. The case addresses two recurring federal sentencing issues:

What “reason to believe” means for the firearms-trafficking enhancement when the buyer is an undercover officer; and
Whether applying that enhancement alongside a separate enhancement for the number of firearms amounts to impermissible “double counting.”

The court reaffirmed that “reason to believe” is an objective, probable-cause-like standard requiring only a “fair probability” that the transferee would unlawfully use or dispose of the weapons. On the facts—interest in illegal “switches,” use of a secret car compartment for the guns, repeated drug purchases, and dealing with an unlicensed seller—the enhancement was proper. The panel also held there was no double counting because the enhancements addressed distinct aspects of Pagan’s conduct.

Summary of the Opinion

Pagan pleaded guilty to three counts of distributing crack cocaine, one count of unlicensed firearms dealing, and two counts of felon-in-possession. The district court applied a four-level firearms-trafficking enhancement under § 2K2.1(b)(5) (2021) based on Application Note 13(A), which required: (i) transfer of two or more firearms and (ii) knowledge or reason to believe the recipient could not lawfully possess or intended to use/dispose of the firearms unlawfully. The court also applied a two-level quantity enhancement for selling three to seven firearms.

On appeal, Pagan challenged the trafficking enhancement, arguing he lacked reason to believe the undercover agent could not lawfully possess or would use the guns unlawfully, and claimed the court impermissibly double counted by stacking the trafficking enhancement with the quantity enhancement. The Sixth Circuit rejected both arguments, holding:

“Reason to believe” equates to a probable-cause “fair probability” standard; the facts here easily met that threshold.
Stacking the trafficking enhancement with the quantity enhancement and a base offense level driven by other factors did not punish the same conduct twice; each addressed a distinct aspect of the offense.

Although the Guidelines range was 121–151 months (after the enhancements), the district court varied downward to 100 months. The Sixth Circuit affirmed the judgment.

Detailed Analysis

Factual Background and Procedural Posture

After contacting a co-actor (Angel Santiago), an undercover agent bought crack cocaine from Pagan on three occasions (May 30, June 6, and June 12, 2023). During these interactions, Pagan:

Confirmed he sold firearms and had “multiple sources” and could make guns on a 3D printer;
Agreed to sell two guns on June 12 (a Taurus revolver with six rounds and a Springfield pistol with an extended magazine holding 29 rounds) and three more on June 14 (a shotgun with 23 shells, a Smith & Wesson pistol with 11 rounds, and a Glock pistol with 21 rounds);
Responded to the agent’s inquiry about illegal “switches” (devices converting semiautomatic weapons into fully automatic ones) by saying he would check with his supplier;
Observed the agent place the guns in a hidden compartment in the agent’s vehicle; and
Sold drugs in tandem with the firearms deals.

Pagan pleaded guilty to six counts. The plea agreement acknowledged the government might seek the then-applicable four-level firearms-trafficking enhancement. Over Pagan’s objection, the district court applied the enhancement and rejected a double-counting challenge. Pagan appealed only the enhancement issues.

The Guidelines Framework

The 2021 version of § 2K2.1(b)(5) called for a four-level increase if the defendant “engaged in the trafficking of firearms.” The parties accepted Application Note 13(A) as a permissible interpretation. The Note required:

The defendant “transported, transferred, or otherwise disposed of two or more firearms to another individual”; and
The defendant “knew or had reason to believe” that at least one of those firearms would reach:
- an “individual whose possession or receipt of the firearm would be unlawful,” or
- an “individual who intended to use or dispose of the firearm unlawfully.”

Application Note 13(B) narrowly defined “individual whose possession or receipt of the firearm would be unlawful” to include only persons convicted of a crime of violence, a controlled-substance offense, a misdemeanor crime of domestic violence, or those under a criminal justice sentence at the time. The government did not rely on this “unlawful possession” prong here because the buyer was an undercover agent. Instead, it invoked the “intended to use or dispose of the firearm unlawfully” prong.

Central to the case is the meaning of “had reason to believe.” The Sixth Circuit reaffirmed its prior articulation that this language sets an objective, probable-cause-like standard—requiring no more than facts establishing a “fair probability” of unlawful use or disposal—rather than demanding subjective knowledge or certainty.

Precedents Cited and Their Role

United States v. McKenzie, 33 F.4th 343 (6th Cir. 2022): The court grounded “reason to believe” in the familiar probable cause framework. It “does not set a high bar,” requiring only a “fair probability” of unlawful use or possession. Pagan’s panel leaned heavily on McKenzie’s objective approach and its admonition that innocent explanations do not defeat probable cause.
District of Columbia v. Wesby, 583 U.S. 48 (2018), and Florida v. Harris, 568 U.S. 237 (2013): Cited via McKenzie to reinforce that probable cause is a practical, common-sense standard, and that officers (or, here, the sentencing court applying an objective standard) need not rule out innocent explanations.
United States v. Pawlak, 822 F.3d 902 (6th Cir. 2016), United States v. Henry, 819 F.3d 856 (6th Cir. 2016): Confirm that sales to an undercover agent do not categorically preclude the trafficking enhancement; the focus is on the defendant’s knowledge or reason to believe based on the facts known at the time.
United States v. Lumpkin, 751 F. App’x 894 (6th Cir. 2019); United States v. Torres, 644 F. App’x 663 (6th Cir. 2016); United States v. Freeman, 640 F.3d 180 (6th Cir. 2011): Illustrate that guns sold in drug trafficking contexts—e.g., to dealers needing protection—can support the inference of intended unlawful use.
United States v. Turner, 698 F. App’x 803 (6th Cir. 2017): Acceptance of “stolen or otherwise ‘dirty’” guns, combined drug-and-gun transactions, and “parked car dealing[s]” are red flags indicating unlawful use or disposal; the court invoked Turner specifically when discussing the hidden compartment and transaction setting.
United States v. Jenkins, 528 F. App’x 483 (6th Cir. 2013): Sales of guns lacking serial numbers and illegal sawed-off shotguns, along with advice on converting weapons, supported the enhancement; cited here to analogize the significance of a buyer’s overt interest in illegal “switches.”
United States v. Moody, 915 F.3d 425, 430 (7th Cir. 2019) (Barrett, J.), United States v. Harris, 719 F. App’x 946 (11th Cir. 2018), and United States v. Green, 360 F. App’x 521 (5th Cir. 2010): The court distinguished these out-of-circuit decisions. Moody’s caution that “off-the-book gun sales” do not automatically establish unlawful use was inapplicable because Pagan’s case involved additional red flags (switches, secret compartment, drug buys). Green’s concern about a silent record did not apply because the facts were undisputed and robust.
United States v. Duke, 870 F.3d 397 (6th Cir. 2017); United States v. Rupp, 2023 WL 370908 (6th Cir. Jan. 24, 2023); United States v. Battaglia, 624 F.3d 348 (6th Cir. 2010): Double-counting framework. Enhancements may be stacked when they address distinct aspects of the offense. Battaglia’s “distinct aspects” test guided the panel’s conclusion that there was no double counting here.
United States v. Saine, 2024 WL 3508691 (6th Cir. July 23, 2024): Cited for the proposition that the § 2K2.1(b)(1)(A) quantity enhancement targets the number of firearms—distinct from the trafficking rationale.

The Court’s Legal Reasoning Applied to Pagan

1) The “Reason to Believe” Standard and Its Objective Nature

The panel emphasized that “reason to believe” is an objective standard akin to probable cause. It does not require proof of the defendant’s subjective belief but asks whether known facts would lead a reasonable person to conclude there was a fair probability the recipient intended unlawful use or disposal. The court expressly contrasted this with the “knew” prong of the commentary, which would have demanded subjective knowledge.

2) Facts that Created a “Fair Probability” of Unlawful Use or Disposal

The court identified several mutually reinforcing “red flags”:

Unlicensed source: Pagan admitted unlicensed firearms dealing (he pleaded guilty to 18 U.S.C. § 922(a)(1)(A)). A buyer seeking guns from an unlicensed seller rather than a licensed dealer suggests illicit purposes. See Pawlak.
Interest in illegal conversion devices: The agent asked for illegal “switches” to convert semiautomatics to fully automatic weapons. This explicit interest in illegal accessories indicated intended unlawful use. See Jenkins.
Concealment behavior: Pagan personally observed the agent hide guns in a secret vehicle compartment. Coupled with a parking-lot transaction, the concealment supported an inference of unlawful use or disposal. See Turner.
Drug activity nexus: The agent repeatedly bought crack cocaine from Pagan, showing ongoing criminal activity connected to the gun sales. See Turner; Freeman; Lumpkin.

Together, these facts created more than a “fair probability” of unlawful use or disposal, satisfying Application Note 13(A)(ii). That the buyer was an undercover officer did not matter; the objective test focuses on what Pagan reasonably should have inferred from the facts he knew, not on the officer’s actual intent or legal status.

3) Pagan’s Counterarguments Rejected

Hidden compartments are not per se illegal: True, but the probable cause inquiry tolerates innocent explanations; it asks only whether unlawful use is fairly probable given the totality. See Wesby; McKenzie.
Uncertainty about the illegality of “switches”: The relevant issue is the buyer’s demonstrated interest in making lawful firearms unlawful, not the seller’s legal acumen about accessories. The “switch” request objectively signals illicit purposes.
No stated plan for the guns: Explicit statements are not required; circumstantial facts may suffice to show a fair probability of unlawful use.
Subjective versus objective standard: The enhancement’s “reason to believe” prong is objective. Pagan’s argument that the district court applied a “reasonable person” lens was not error; it was required. See McKenzie.

4) Standard of Review

The panel noted that Sixth Circuit decisions have treated the mixed question presented here under both de novo and deferential standards (compare Pawlak with Freeman) but found reconciliation unnecessary because Pagan’s claim failed under either standard. See McKenzie.

Double Counting Analysis

Double counting occurs when two enhancements punish the same aspect of a defendant’s conduct, unless the Guidelines authorize it. The Sixth Circuit did not need to reach authorization because there was no double counting at the threshold. The enhancements addressed different conduct:

Base offense level 22 (§ 2K2.1(a)(3)): Driven by the type of firearms (semiautomatics capable of accepting large-capacity magazines) and Pagan’s prior controlled-substance conviction—foundational offense characteristics, not trafficking intent.
Quantity enhancement (+2 under § 2K2.1(b)(1)(A)): Punishes selling “between three and seven firearms,” focusing solely on volume, not how the guns would be used.
Firearms trafficking enhancement (+4 under § 2K2.1(b)(5)): Targets the seller’s reason to believe about unlawful use or disposal by the recipient, irrespective of quantity or weapon type.

Because each enhancement addressed a different facet—weapon type/prior record, quantity, and unlawful-use risk—stacking them did not penalize the same conduct twice. See Battaglia; Saine.

Impact and Implications

1) Reaffirmation of an Objective, Low Threshold

The decision reinforces that “reason to believe” operates like probable cause: the government need only show facts supporting a fair probability of unlawful use or disposal. Courts will not require admissions of illegal plans or exclude plausible innocent explanations. This has practical consequences:

Sales to undercover agents can satisfy the trafficking enhancement where the seller hears or sees “red flags” like interest in illegal conversion devices, combined drug-and-gun dealings, or concealment behaviors.
Defense arguments that those facts have innocent explanations will ordinarily be insufficient if the totality still shows a fair probability of illicit use.

2) Distinguishing Undercover Purchases from “Off-the-Books” Purchases

The court explicitly declined to adopt any categorical rule that off-the-books sales always equal trafficking, aligning with Seventh Circuit caution in Moody. But it made clear that where additional indicators are present (here, “switches,” hidden compartments, drug trade), the enhancement is justified. This calibrated approach preserves fact sensitivity while setting a readily satisfied evidentiary bar.

3) Guidance on Stacking Enhancements in Firearms Sentences

The ruling provides clear guidance for sentencing courts: base levels tied to weapon type and criminal history, number-of-guns enhancements, and trafficking enhancements serve different functions and can be stacked without double counting where each rests on distinct facts. Expect prosecutors to methodically develop records showing:

Weapon characteristics and a defendant’s record (base offense);
Quantity of weapons sold (b)(1)(A); and
Objective indicators of unlawful use or disposal (b)(5).

4) Practical Takeaways for Litigants

For the government: Elicit and document “red flags” such as explicit interest in illegal conversion devices, concealment methods (e.g., secret compartments), and concurrent drug transactions. These facts are often sufficient to establish the requisite “fair probability.”
For the defense: Challenge the totality by emphasizing lawful explanations and the absence of indicators of unlawful use; differentiate “off-the-books” purchases without more; and probe the record for gaps (as in Green) or for factors showing lawful intent by the buyer. But recognize the low threshold of the objective standard.
For district courts: Analyze the totality and make findings connecting specific facts to the inferences about unlawful use, and assess each enhancement’s distinct rationale to avoid true double counting.

Complex Concepts Simplified

“Reason to believe” vs. “knowledge”: “Knowledge” means the defendant actually knew a fact. “Reason to believe” is objective: would a reasonable person, knowing what the defendant knew, conclude there is a fair probability of unlawful use or disposal? The latter does not require certainty.
Probable cause and “fair probability”: A practical standard used in criminal procedure. It allows action based on a sensible assessment of risk; authorities (and here, sentencing courts) need not dispel every innocent explanation.
Firearms trafficking enhancement (§ 2K2.1(b)(5) (2021)): A four-level increase for transferring two or more guns with reason to believe of unlawful possession or unlawful use/disposal by a recipient.
Application Note 13(B)’s narrow “unlawful possession” category: Covers only specific statuses (e.g., certain prior convictions or being under sentence). When that prong is unavailable (as with undercover agents), the “unlawful use/disposal” prong can still apply based on the facts.
“Switches”: Colloquial term for devices that convert semiautomatic firearms into fully automatic weapons. An expressed interest in obtaining them is a powerful indicator of unlawful intent.
Double counting: Impermissible only when two enhancements punish the same feature of the offense; permissible when each addresses a distinct aspect (e.g., weapon type, quantity, unlawful-use risk).

Conclusion

United States v. Pagan robustly reaffirms that the firearms-trafficking enhancement’s “reason to believe” requirement is satisfied by a probable-cause-like showing—facts indicating a fair probability of unlawful use or disposal suffice, even when the buyer is an undercover officer. The panel’s careful inventory of red flags—interest in illegal conversion devices, secret compartments, repeated drug buys, and purchasing from an unlicensed dealer—provides a practical checklist for future cases. On the sentencing architecture, the decision underscores that base offense characteristics, quantity enhancements, and trafficking enhancements address different sentencing concerns and may be applied together without double counting.

Although unpublished, the opinion offers persuasive guidance in the Sixth Circuit on how to evaluate “reason to believe” under § 2K2.1 and how to avoid conflating distinct enhancements under the firearms guideline. Its bottom line is straightforward: when the totality of the circumstances indicates a fair probability of unlawful use or disposal, the trafficking enhancement applies; and when enhancements target different facets of the conduct, stacking them is proper.