Proximity Is Not Probable Cause: The Third Circuit Affirms a Nexus Requirement for Warrantless Automobile Searches When Contraband Departs in a One-Way Transfer

Introduction

In United States v. Diaz Borrome (3d Cir. Oct. 9, 2025) (non-precedential), the Third Circuit affirmed the suppression of a firearm recovered from the center console of a Jeep following a warrantless search conducted under the automobile exception. The government appealed the District Court of the Virgin Islands’ suppression order, arguing agents had probable cause to search the vehicle after observing a jet-ski rendezvous associated with suspected drug trafficking at a secluded beach inside a gated community. The panel—emphasizing the difference between reasonable suspicion and probable cause, and the need for a particularized nexus between suspected criminal activity and the place to be searched—held that the government failed to carry its burden to show a fair probability that contraband or evidence of a crime would be found inside the Jeep at the time of the search.

Key issues included: whether the agents’ observations (a jet-ski duffel-bag transfer typical of smuggling, a Jeep parked nearby, wet and sandy occupants, one visible firearm, and reports of the jet skis fleeing law enforcement) collectively established probable cause to search the Jeep; whether the agents could reasonably infer that the Jeep’s occupants were the same individuals who loaded the jet skis; and whether, even assuming that identity, there was reason to believe contraband or evidence of a crime would be inside the Jeep given that the apparent transfer was one-way from shore to sea.

Parties: The United States (Appellant) challenged suppression of the second firearm. Esteban Rafael Diaz Borrome (Appellee), the Jeep’s driver, had moved to suppress two firearms; the District Court suppressed only the second firearm found in the center console (lacking a visible serial number), not the first firearm observed in plain view in the driver’s seatback pocket. Judge Freeman authored the opinion, joined by Judges Restrepo and McKee.

Summary of the Opinion

The Third Circuit affirmed the suppression order. It agreed that officers had reasonable suspicion to stop the Jeep at the gate to the Botany Bay community based on aerial intelligence and timing. But it held that the government did not establish probable cause to search the Jeep under the automobile exception. The court accepted that the beachside duffel-bag handoff was strongly indicative of drug smuggling. Nonetheless, it found two critical gaps in the government’s proof:

The record did not support a fair inference that the Jeep’s six occupants were the same individuals who performed the jet-ski handoff. The aerial agent stopped watching the beach after the jet skis departed; no agent observed anyone enter or leave the Jeep; and there was no testimony comparing the beach actors to the occupants.
Even if the occupants were the same people, the observed transaction was one-way (from shore to jet skis). That made it unreasonable to believe contraband or evidence would likely be inside the Jeep at the time of the search.

The court also discounted other circumstances as too equivocal to supply probable cause: wet and sandy items are unsurprising near a beach; possession of a firearm is not per se illegal in the Virgin Islands; and there was no testimony that the first firearm (which bore a serial number) was suggestive of criminality. Reports that the jet skis fled law enforcement did not bridge the nexus to the Jeep’s interior. Under the totality of circumstances, the government did not meet its preponderance burden to show probable cause that the Jeep contained contraband or evidence of a crime. The suppression of the second firearm was therefore affirmed.

Detailed Analysis

Precedents Cited and Their Role

United States v. Mundy, 621 F.3d 283 (3d Cir. 2010): Reiterates the bedrock principle that warrantless searches are presumptively unreasonable under the Fourth Amendment unless an exception applies. The court frames its analysis within this presumption and places the burden on the government to justify the search.
Collins v. Virginia, 584 U.S. 586 (2018): Confirms the automobile exception allows warrantless searches of vehicles when officers have probable cause. The court accepts the exception’s applicability in principle but stresses the prerequisite: genuine probable cause that the vehicle contains evidence or contraband.
District of Columbia v. Wesby, 583 U.S. 48 (2018): Emphasizes that probable cause is a “fluid concept” based on probabilities under the totality of the circumstances, requiring only a substantial chance of criminal activity, not certainty. The Third Circuit uses Wesby’s framing but finds the government’s chain of inferences too attenuated.
United States v. Donahue, 764 F.3d 293 (3d Cir. 2014): Articulates the methodology—evaluate historical facts and ask whether, viewed objectively, they amount to probable cause—and places the burden on the government to prove an exception by a preponderance. The court follows Donahue’s approach and finds the government’s showing lacking.
Colorado v. Bannister, 449 U.S. 1 (1980) (per curiam): Recognizes that when probable cause exists, officers may seize evidence from a vehicle without a warrant. The Third Circuit underscores that the threshold question—probable cause that the vehicle contains evidence—was not satisfied here.
Kansas v. Glover, 589 U.S. 376 (2020), and United States v. Amos, 88 F.4th 446 (3d Cir. 2023), quoting Illinois v. Wardlow, 528 U.S. 119 (2000): These authorities delineate the gulf between reasonable suspicion and probable cause. The panel acknowledges that reasonable suspicion justified the stop but makes clear that this less demanding standard did not authorize a full search of the Jeep.
United States v. Outlaw, 138 F.4th 725 (3d Cir. 2025): Cited for appellate jurisdiction compliance, not merits. Included to clarify the court’s authority to hear the government’s appeal under 18 U.S.C. § 3731.

Together, these cases framed two controlling inquiries: (1) whether the government’s facts, taken collectively, created a fair probability that the Jeep’s occupants were the same individuals involved in the duffel-bag handoff; and (2) whether there was a fair probability that contraband or evidence would be found inside the Jeep. The panel answered both in the negative.

The Court’s Legal Reasoning

The government’s probable-cause theory rested on three premises:

The men who loaded fuel and duffels onto the jet skis on the beach were the same men found in the Jeep;
The handoff at the jet skis involved criminal activity (i.e., drug smuggling); and
Contraband or evidence of a crime would be found inside the Jeep.

The panel effectively accepted premise (2) but rejected premises (1) and (3), and that dooms the automobile-exception argument.

Identity and linkage (Premise 1): No agent saw anyone exit or return to the Jeep; no agent tracked the men after the jet skis departed; there was a 20-minute gap before the Jeep reached the gate; and there was no testimony about physical similarities or clothing. The wet and sandy shoes, a wet towel, and a damp floorboard were just as consistent with lawful beachgoing as with illicit activity. The stop was justified by reasonable suspicion, but those equivocal markers did not elevate the suspicion to probable cause that these occupants were the same people who performed the handoff.
Nexus to the vehicle and its contents (Premise 3): Even assuming the Jeep’s occupants were the beach actors, the court found no fair probability that evidence would be inside the Jeep. The transaction observed was “one-way”—fuel and duffels went onto the jet skis, which then departed. That fact cut strongly against the inference that contraband remained in or returned to the Jeep. While the automobile exception permits searches for “evidence of a crime” as well as contraband, the court required a concrete, particularized reason to think such evidence would be in the Jeep at that time. The government did not supply it.
Lawful gun possession and ambiguity: The first firearm, visible in the seatback pocket, did not contribute meaningfully to probable cause because firearm possession is not per se unlawful in the Virgin Islands, and agents identified no indicia of illegality specific to that weapon (it bore a serial number, unlike the second gun later found). The court refused to bootstrap a full-blown search from a lawfully possessed gun in plain view.
Temporal and informational gaps: The aerial agent ceased beach surveillance when the jet skis left, and no one maintained eyes on the Jeep. Reports that the jet skis fled law enforcement did not meaningfully tie the Jeep to ongoing criminal activity or to evidence likely stored in its console.

Against this backdrop, and applying Wesby and Donahue’s totality-of-circumstances analysis, the panel held the government failed to show by a preponderance that probable cause existed. Because the automobile exception did not apply, the warrantless search of the center console violated the Fourth Amendment and the resulting firearm was properly suppressed.

What This Decision Adds: The “Nexus” and “One-Way Transfer” Emphasis

While non-precedential, the opinion sharpens two practical guideposts for automobile searches:

Nexus requirement to vehicle contents: Probable cause must be directed to the place to be searched—the interior of the vehicle—and not merely to generalized suspicion about the occupants’ involvement in criminal activity. A fair probability that evidence is in the car is required, not just a fair probability that the occupants committed a crime somewhere nearby.
One-way transfer weakens the inference: Where agents observe contraband or materials depart the scene with others (here, on jet skis) and do not observe anything being returned to or stored in the car, the inference that the car presently contains contraband or evidence is attenuated. The “one-way” character of the handoff was central to the court’s rejection of probable cause.

Impact and Practical Implications

Although not binding circuit precedent, this decision is likely to be persuasive in the Third Circuit (including the Virgin Islands) and beyond for several reasons:

Law enforcement operations: Agents should maintain continuous observation linking a suspect vehicle to the criminal act (e.g., confirming that actors seen at the scene enter the vehicle) and articulating why evidence is likely inside the vehicle at the time of search. Absent that, officers risk suppression of evidence discovered during warrantless searches.
Editing assumptions out of probable cause: The opinion warns against piling assumption upon assumption. Proximity to suspicious activity, ambiguous beach-related wetness, and a lawfully possessed firearm do not, without more, create probable cause for an intrusive search.
Scope and timing: If a suspected handoff is outbound (to a boat, jet ski, or third party), probable cause to search a nearby car is weakened unless agents can articulate reasons why evidence likely remained or returned to that car (e.g., residual packaging, communications devices, ledgers, or direct observation).
Distinguishing stop from search: The decision reinforces that reasonable suspicion justifies a stop and temporary detention, but a search of the vehicle’s compartments requires the higher probable cause threshold. Practitioners should be alert to government attempts to conflate the two standards.
Firearms as a “plus factor”: In jurisdictions where firearm possession is lawful, the mere presence of a gun—without illegality markers such as obliterated serial numbers, prohibited possessor status, or other specific indicia—adds little to a probable cause calculus. Here, the gun lacking a visible serial number was discovered only after the unlawful search; it could not retroactively justify the search.

For defense counsel, Diaz Borrome supplies language emphasizing the necessity of a particularized nexus to the car’s contents and the insufficiency of equivocal facts. For prosecutors, it underscores the need to present concrete, observable links and to consider obtaining a warrant where feasible, especially when the evidentiary path to the vehicle is inferential rather than observed.

Complex Concepts Simplified

Reasonable suspicion vs. probable cause: Reasonable suspicion is a lower standard that allows brief stops and detentions based on specific, articulable facts. Probable cause is stronger—requiring a fair probability (substantial chance) that evidence of a crime will be found in the place to be searched. The former justifies a Terry stop; the latter is needed to search a car without a warrant under the automobile exception.
Automobile exception: A doctrine permitting warrantless searches of vehicles if officers have probable cause to believe the vehicle contains contraband or evidence of a crime. Mobility and diminished expectations of privacy underpin the exception, but the probable cause requirement is non-negotiable.
Totality of the circumstances: Courts consider all facts together, not in isolation. However, stacking ambiguous facts without a firm nexus to the search target does not satisfy probable cause.
Nexus to the place searched: Probable cause must tie the suspected evidence to the specific location to be searched (here, the Jeep’s interior). Suspicion that people have engaged in crime nearby does not automatically justify searching their car.
Non-precedential decision: In the Third Circuit, a non-precedential opinion does not bind future panels (I.O.P. 5.7), but it may be cited for its persuasive value, especially on similar facts.
Government’s burden: When invoking an exception to the warrant requirement, the government must prove its applicability by a preponderance of the evidence—i.e., that it is more likely than not that the exception’s criteria are met.

Conclusion

United States v. Diaz Borrome reinforces a key Fourth Amendment constraint on vehicle searches: proximity to suspected criminal activity—even activity strongly indicative of drug trafficking—does not itself create probable cause to search a vehicle. The automobile exception demands a particularized, evidence-based nexus showing a fair probability that contraband or evidence will be found inside the car. Where the observed transaction is one-way and officers lack observations tying the car or its occupants to the contraband’s ongoing presence, a warrantless search will not stand.

The decision’s enduring message is both simple and significant: suspicion must be channeled into specific, articulable reasons to believe evidence is in the place searched. Absent that nexus, the Fourth Amendment bars the government from converting reasonable suspicion into a full search. Even as non-precedential, the opinion offers a clear roadmap for courts and practitioners confronting similar maritime or beachside interdictions, emphasizing that the automobile exception is powerful but not boundless.