No. 20-3467 ___________________________

United States of America

lllllllllllllllllllllPlaintiff - Appellee

v.

Vernon Shumaker

lllllllllllllllllllllDefendant - Appellant ____________

Appeal from United States District Court for the Southern District of Iowa - Central ____________

Submitted: September 24, 2021 Filed: December 29, 2021 ____________ Before SMITH, Chief Judge, GRUENDER and STRAS, Circuit Judges. ____________ SMITH, Chief Judge.

Vernon Shumaker conditionally pleaded guilty to one count of being a felon and drug user in possession of a firearm, in violation of 18 U.S.C. §§ 922(g)(1), 922(g)(3), and 924(a)(2), after the district court denied his motion to suppress evidence. Shumaker had moved to suppress evidence gathered during a stop and search of his vehicle. Shumaker argued that the officers lacked reasonable suspicion to stop him because they could not have smelled marijuana while driving behind him. Alternatively, he argued that even if the officers smelled marijuana, they did not have a particularized suspicion that the smell was emanating from his vehicle. The district court1 denied the suppression motion. It found credible the officers’ testimony that they smelled marijuana while driving behind Shumaker and further found that the officers’ suspicion was particularized to Shumaker’s vehicle. Shumaker now appeals the district court’s denial of the suppression motion. We affirm.

I. Background A. Facts This case depends heavily upon its facts. A thorough factual summary is therefore in order. For a six-month period each year (spring to fall), the Des Moines Police Department (DMPD) operates a Special Enforcement Team (SET). The last day that the SET operated in 2019 was October 5, 2019. The SET does not take service calls; instead, it patrols high-crime areas to actively search for criminal activity. The goal of the SET is “to make as many stops as possible within the legal realm to have interaction with people, to attempt to seize narcotics, people with warrants, and/or firearms.” R. Doc. 38, at 20.

SET Officers Ryan Steinkamp, Brian Minnehan, and Ryan Garrett (collectively, “the officers”) are familiar with the smell of marijuana because they encounter it frequently. According to Officer Minnehan, when an officer encounters a marijuana odor while driving, the officer attempts to identify the odor’s source by following the vehicle believed to be the odor’s source and observing whether the odor remains constant. If the odor dissipates, then the officer does not stop the vehicle.

1 The Honorable Rebecca Goodgame Ebinger, United States District Judge for the Southern District of Iowa.

-2- On October 5, 2019, the officers were on patrol in a marked squad car. Officer Steinkamp drove the car, Officer Garrett sat in the front seat, and Officer Minnehan sat in the back seat. The squad car’s front windows were up, but its back windows were down. At 5:49 p.m., the officers were driving westbound on a city street behind a black sedan that had its windows up. According to weather records, the wind was traveling between 13 and 17 miles per hour. The officers did not smell marijuana while driving behind the black sedan.

As the officers approached a four-way intersection, they saw a red Chevrolet Impala traveling eastbound abruptly turn left in front of the oncoming black sedan. The Impala’s “passenger side window was down.” Id. at