United States v. Brown

Case: 25-50728 Document: 67-1 Page: 1 Date Filed: 08/17/2026

United States Court of Appeals for the Fifth Circuit United States Court of Appeals ____________ Fifth Circuit FILED No. 25-50728 August 17, 2026 Summary Calendar Lyle W. Cayce ____________ Clerk United States of America, Plaintiff—Appellee, versus William Jefferson Brown, Jr., Defendant—Appellant. ______________________________ Appeal from the United States District Court for the Western District of Texas USDC No. 6:23-CR-177-1 ______________________________ Before Clement, Haynes, and Ramirez, Circuit Judges. † Per Curiam: * William Jefferson Brown Jr. appeals his conviction for possessing a firearm as a convicted felon in violation of 18 U.S.C. § 922(g)(1). He argues that the district court should have suppressed evidence of the firearm

_____________________ † Judge Haynes concurs in the judgment only.

Case: 25-50728 Document: 67-1 Page: 2 Date Filed: 08/17/2026

No. 25-50728 because it was seized during an unconstitutionally prolonged traffic stop.

Finding no error, we AFFIRM.

I Brown was arrested after a traffic stop that arose from a narcotics surveillance operation. A detective received a tip from a confidential informant that narcotics were going to be delivered to and sold from a residence in Killeen, Texas, so the detective surveilled the residence. The detective learned that two brothers with extensive criminal history in selling narcotics lived at the residence. The informant had told the detective that he would leave the residence via rideshare because the informant was not allowed to be in the residence during narcotics deliveries. When the detective arrived at the residence, he observed the informant leave in a rideshare. Soon after, the detective watched several people park at the residence, walk into the house, stay for a minute or two, and then drive away. Based on his experience, the detective believed this behavior was indicative of narcotics sales.

As part of the operation, the detective dispatched officers to follow vehicles leaving the residence and stop them if they observed a traffic offense.

The first driver officers stopped after leaving the residence was arrested for possession of methamphetamine. Shortly after that driver left the residence, the detective observed Brown park at the residence, exit his vehicle carrying a backpack, enter the residence, and leave after a few minutes. As Brown drove off, the detective radioed another officer, who followed Brown in an unmarked vehicle. That officer saw Brown fail to stop before a stop line and crosswalk. See Tex. Transp. Code Ann. § 544.010(c). The officer then relayed that information to Officer Justin Asmus, a canine officer who was driving a marked vehicle.

Case: 25-50728 Document: 67-1 Page: 3 Date Filed: 08/17/2026

No. 25-50728

Officer Asmus initiated a traffic stop. When Officer Asmus asked for Brown’s license and proof of insurance, Brown immediately handed over his license, but he had to call his wife for the insurance information. Officer Asmus then asked Brown to step out of the vehicle and move to the sidewalk to talk. Brown initially refused, but he eventually exited the vehicle after calling his wife and arguing with Office Asmus for three minutes. Once out of the vehicle, Brown engaged Officer Asmus in unrelated conversation for two minutes while Officer Asmus conducted the traffic stop. Brown’s wife then sent him proof of insurance, which Brown showed to Officer Asmus.

Officer Asmus asked for consent to search Brown’s vehicle; Brown declined.

Officer Asmus immediately informed Brown that he was going to conduct a dog sniff. Officer Asmus’s dog alerted to the driver’s side door of Brown’s vehicle within one minute. Officer Asmus then searched Brown’s vehicle, in which he found a revolver in Brown’s backpack, but no narcotics.

In all, fourteen minutes elapsed from the time Officer Asmus stopped Brown’s vehicle to the moment the dog alerted.

Brown, who had previously been convicted of three felonies, was charged with unlawfully possessing a firearm in violation of 18 U.S.C. § 922(g)(1). Brown moved to suppress the firearm, arguing, in part, that it was seized in violation of the Fourth Amendment because Officer Asmus unreasonably prolonged the traffic stop. After a hearing, the magistrate judge recommended that the district court deny the motion. The district court adopted the recommendation over Brown’s objection and denied the motion.

Brown entered a conditional plea agreement, and the district court sentenced him to 120 months of imprisonment. Brown timely appealed.

II On appeal, Brown argues that the district court erred in denying his motion to suppress because Officer Asmus did not diligently pursue, or Case: 25-50728 Document: 67-1 Page: 4 Date Filed: 08/17/2026

No. 25-50728 otherwise unreasonably prolonged, the traffic stop. We review the district court’s findings of fact for clear error and its conclusions of law de novo.

United States v. Reyes, 963 F.3d 482, 487 (5th Cir. 2020).

Traffic stops are seizures subject to the Fourth Amendment’s protection “against unreasonable searches and seizures.” U.S. Const. amend. IV. We assess the reasonableness of a traffic stop under Terry v. Ohio, 392 U.S. 1 (1968), meaning we must determine if the stop was “justified at its inception” and “whether it was reasonably related in scope to the circumstances which justified the [stop] in the first place.” Id. at 20; see United States v. Andres, 703 F.3d 828, 832 (5th Cir. 2013). Brown does not challenge the initial stop of his vehicle, so we must decide only whether the duration of the traffic stop was reasonable.

The purpose of a traffic stop is to address a traffic violation, so a stop “may last no longer than is necessary to effectuate that purpose.” Rodriguez v. United States, 575 U.S. 348, 354 (2015) (cleaned up). “Authority for the seizure thus ends when tasks tied to the traffic infraction are—or reasonably should have been—completed.” Id. Such tasks often include “checking the driver’s license, determining whether there are outstanding warrants against the driver, and inspecting the automobile’s registration and proof of insurance.” Id. at 355. At bottom, “officers must diligently pursue the investigation of the traffic violation.” Reyes, 963 F.3d at 487.

That said, an officer may take additional investigative steps unrelated to the purpose of the traffic stop, but “he may not do so in a way that prolongs the stop, absent the reasonable suspicion ordinarily demanded to justify detaining an individual.” Rodriguez, 575 U.S. at 354. “If the officer develops reasonable suspicion of [additional criminal] activity ‘in the course of the stop and before the initial purpose of the stop has been fulfilled, then the detention may continue until the new reasonable suspicion has been dispelled Case: 25-50728 Document: 67-1 Page: 5 Date Filed: 08/17/2026

No. 25-50728 or confirmed.’” Reyes, 963 F.3d at 487–88 (quoting United States v. Banuelos- Romero, 597 F.3d 763, 767 (5th Cir. 2010)).

Here, Officer Asmus did not prolong the traffic stop, and he diligently pursued his investigation of Brown’s alleged traffic violation. Officer Asmus promptly requested Brown’s license and registration, and he questioned Brown about his out-of-date driver’s license. Before Officer Asmus initiated the dog sniff, any delays in the traffic stop were attributable to Brown’s small talk, arguing, and inability to locate his proof of insurance, not Officer Asmus’s inaction or delay. And the dog sniff did not “measurably extend the duration of the stop” because Officer Asmus’s dog was already on the scene and alerted within one minute. Rodriguez, 575 U.S. at 355 (quoting Arizona v. Johnson, 555 U.S. 323, 333 (2009)). Thus, the stop lasted no longer than necessary to effectuate its purpose. See id. at 354.

Moreover, the dog sniff was independently justified because it was “supported by reasonable suspicion of additional criminal activity.” Reyes, 963 F.3d at 487. Officer Asmus knew that his colleagues were investigating a residence associated with narcotics trafficking. He also knew that Brown had entered the residence carrying a backpack, stayed for a few minutes, and drove away. When Officer Asmus pulled Brown over, he saw Brown reach over to secure something in the passenger seat. These factors “by themselves may appear innocent,” but “in the aggregate,” they provided Officer Asmus “a particularized and objective basis for suspecting criminal activity.” Id. at (quoting United States v. Ibarra-Sanchez, 199 F.3d 753, 759 (5th Cir. 1999)).

III Officer Asmus did not violate the Fourth Amendment because he did not unreasonably prolong the traffic stop, and the dog sniff was supported by reasonable suspicion. We AFFIRM.