United States v. Reymundo Pacheco, 996 F.3d 508

Deputy Shiels stopped Yanez after observing speeding and lane drifting; Shiels observed the car was a rental from California and ‘‘lived in’’ with food and a soda case.
Shiels issued a warning but asked Yanez to wait while he conducted a canine sniff; parties dispute whether the dog alerted, but the district court left that unresolved.
Inside the patrol vehicle, Shiels observed Yanez acting unusually nervous (avoiding eye contact, visible stomach fluttering) and giving vague or inconsistent answers about his itinerary.
Shiels obtained consent to search the back seat; he found a spare tire in the passenger compartment and a backpack with only minimal clothing—both explanations from Yanez were implausible.
Based on these factors, Shiels searched the spare-tire compartment in the trunk without a warrant and discovered ~40 pounds of methamphetamine.
Yanez moved to suppress, the district court denied the motion; Yanez conditionally pleaded guilty and appealed the suppression denial.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether the officer had reasonable suspicion to extend the traffic stop to conduct a canine sniff	Yanez: extension was unlawful because the stop should have ended after the warning; available facts did not amount to particularized suspicion	Gov./Shiels: driver’s extreme nervousness, implausible travel plans, lived‑in car, short rental period, and evasive answers gave reasonable suspicion to extend the stop	Court: affirmed—totality of circumstances supplied reasonable suspicion to extend the stop
Whether officer had probable cause to search the trunk (spare‑tire compartment) without a warrant	Yanez: search lacked probable cause; suspicious factors did not rise to fair probability of contraband in trunk	Gov./Shiels: additional facts during consent search (implausible explanations, spare tire in back seat, minimal clothing) elevated suspicion to probable cause for trunk search	Court: affirmed—totality of circumstances (implausible answers + spare tire placement + travel inconsistencies) supported probable cause

Rodriguez v. United States, 575 U.S. 348 (limits on extending a traffic stop beyond mission)
Arizona v. United States v. Arvizu, 534 U.S. 266 (totality‑of‑circumstances test for reasonable suspicion)
District of Columbia v. Wesby, 583 U.S. (2018) (implausible statements can support probable cause)
United States v. Beck, 140 F.3d 1129 (8th Cir. 1998) (court distinguished Beck’s facts on nervousness and rental car factors)
United States v. McCarty, 612 F.3d 1020 (8th Cir. 2010) (unusual one‑way rental plans can supply suspicion)
United States v. Fuse, 391 F.3d 924 (8th Cir. 2004) (nervousness after warning relevant to suspicion)
United States v. Riley, 684 F.3d 758 (8th Cir. 2012) (visible physiological signs of nervousness support suspicion)
United States v. Ortiz‑Monroy, 332 F.3d 525 (8th Cir. 2003) (officer experience may inform suspicion about typical concealment locations)