United States v. Batara-Molina, 60 F.4th 1251

Deputy Coxbill stopped Ian Batara‑Molina for speeding and, on approaching the vehicle, detected a strong "cover" odor coming from inside.
The car was a third‑party rental due to be returned to California in two days; Molina said he planned to extend the rental for one additional day for a short trip to Sioux Falls.
Deputies Rhoades and Coxbill coordinated: Rhoades confirmed Molina’s address while Coxbill retrieved a drug‑sniffing dog that he routinely kept in his patrol car; Molina and Rhoades stepped away from the vehicle as Rhoades finished the warning.
Coxbill walked the dog around the car; the dog alerted and officers searched the trunk, uncovering ~14 pounds of methamphetamine.
Molina moved to suppress, arguing the traffic stop was unlawfully prolonged for the dog sniff and the deputies lacked reasonable suspicion to detain him beyond the traffic mission; the district court denied suppression and Molina pled guilty.
The Tenth Circuit affirmed, assuming arguendo the stop was prolonged but holding the prolongation was supported by reasonable suspicion based principally on the cover odor, the third‑party rental, and the imminent rental expiration.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether prolonging a traffic stop to run a dog sniff required reasonable suspicion and, if so, whether deputies had it	Molina: the stop was delayed for the dog sniff and the deputies lacked reasonable suspicion to do so	Government: deputies had reasonable suspicion based on a strong cover odor plus travel/rental facts to justify the dog sniff	Court: assumed delay but held reasonable suspicion narrowly supported the prolongation by the totality of circumstances (cover odor + third‑party rental + imminent rental expiration)
Which facts may permissibly support reasonable suspicion in this context	Molina: many observations (mispronunciation, coming from California, sleeping at a rest stop, vape pen, little visible luggage) are innocent and cannot be weighed	Government: those cumulative facts contributed to reasonable suspicion	Court: disallowed or minimized several factors — mispronunciation, origin from California, sleeping at a gas station, vape pen, and lack of visible backseat luggage were improper or entitled to little weight; only the odor, third‑party rental, and imminent rental return were credited

Rodriguez v. United States, 575 U.S. 348 (2015) (traffic‑stop mission ends when tasks tied to infraction are completed; unrelated inquiries may not prolong stop absent reasonable suspicion)
United States v. Arvizu, 534 U.S. 266 (2002) (reasonable suspicion assessed under totality of circumstances)
United States v. Frazier, 30 F.4th 1165 (10th Cir. 2022) (even de minimis delays for unrelated inquiries violate Fourth Amendment absent reasonable suspicion)
United States v. Santos, 403 F.3d 1120 (10th Cir. 2005) (limitations on inferring suspiciousness from rental extensions where officer lacked facts about extension costs/attitude)
United States v. Sokolow, 490 U.S. 1 (1989) (aggregate travel factors can support reasonable suspicion in courier cases)
Vasquez v. Lewis, 834 F.3d 1132 (10th Cir. 2016) (cannot rely on a motorist’s state of origin or citizenship to justify detention/search)
United States v. Mendez, 118 F.3d 1426 (10th Cir. 1997) (lack of visible backseat luggage carries little weight when vehicle has a trunk)
United States v. Williams, 271 F.3d 1262 (10th Cir. 2001) (use of third‑party rental is consistent with trafficking and may be suspicious)