United States v. Rocky Thomas Mayfield, 678 F. App'x 437

During a daytime traffic stop for missing license plates and crossing the center line, Officer Allen Schmidt approached a car carrying driver Tina Ganley, front passenger Oscar Delgado, and rear passenger Rocky Mayfield.
Schmidt smelled marijuana when leaning into the vehicle, observed Ganley acting nervous, and saw Mayfield move furtively in the backseat; he removed all occupants, conducted pat-downs, and found about $19,000 on Mayfield.
With no room in the squad car, Schmidt placed all three occupants in vehicles, read Ganley her Miranda rights, and—while Ganley sat in the car—searched the vehicle, finding about one pound of methamphetamine.
At the jail, Delgado told officers there were ten pounds of methamphetamine and some marijuana in a nearby hotel room; a warrant search of the room uncovered methamphetamine, marijuana, paraphernalia, and a firearm.
Mayfield moved to suppress evidence from the vehicle and hotel searches, arguing Schmidt lacked probable cause because Schmidt’s testimony that he smelled marijuana was not credible; the district court denied suppression.
On appeal, the Eighth Circuit reviewed factual findings for clear error and affirmed, finding the district court did not clearly err in crediting Schmidt’s testimony and that the odor of marijuana supplied probable cause under the automobile exception.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether officer had probable cause to search the vehicle	Mayfield: Schmidt’s marijuana-smell testimony was not credible; inconsistencies and extrinsic evidence undermine probable cause	Government: Schmidt smelled marijuana at close range; corroborated by occupants’ admissions and later hotel seizure	Court: Credibility findings entitled to great deference; probable cause existed based on odor of marijuana
Whether evidence from hotel search should be suppressed as fruit of unlawful search	Mayfield: Hotel search flowed from an invalid vehicle search and should be suppressed	Government: Hotel warrant supported by Delgado’s tip and independent probable cause; vehicle search valid	Court: Vehicle search valid, and hotel search supported; evidence admissible
Whether district court clearly erred in crediting officer testimony	Mayfield: Discrepancies and other officers’ inability to smell marijuana show clear error	Government: Discrepancies minor; contemporaneous observations and admissions support credibility	Court: No clear error; credibility determinations are for the trial court and were reasonable
Applicability of automobile exception for warrantless search	Mayfield: Challenges sufficiency of probable cause to invoke exception	Government: Smell of marijuana provides probable cause under established precedent	Court: Automobile exception applies; odor alone suffices for probable cause

United States v. Peltier, 217 F.3d 608 (8th Cir. 2000) (odor of marijuana gives probable cause to search vehicle)
United States v. Neumann, 183 F.3d 753 (8th Cir. 1999) (officer’s drug-detection training and observations can support probable cause)
United States v. Zamora-Lopez, 685 F.3d 787 (8th Cir. 2012) (standard of review for suppression denials: legal conclusions de novo, factual findings for clear error)
United States v. Hogan, 539 F.3d 916 (8th Cir. 2008) (appellate review will affirm suppression rulings unless unsupported by substantial evidence or legal error)
United States v. Annis, 446 F.3d 852 (8th Cir. 2006) (same standard quoted for suppression review)
United States v. Heath, 58 F.3d 1271 (8th Cir. 1995) (credibility assessments are the province of the trial court and rarely disturbed)
United States v. Wright, 739 F.3d 1160 (8th Cir. 2014) (district court credibility findings entitled to particularly great deference)