United States of America v. Vernon Shumaker

United States Court of Appeals
For the Eighth Circuit
___________________________
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

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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.
1The Honorable Rebecca Goodgame Ebinger, United States District Judge for
the Southern District of Iowa.
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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 38. At the intersection, the
officers turned right and started driving northbound on the same street as the Impala.
Shortly after making the right turn, the officers “started smelling the odor of
marijuana, and that’s what drew [their] attention” to the Impala. Id. at 39. The squad
car was approximately 100 meters behind the Impala when the officers first smelled
the odor. The Impala was in the left lane, while the squad car was directly behind the
black sedan in the right lane. The officers did not believe that the black sedan was the
odor’s source because its windows were up and they never smelled marijuana while
following the black sedan before turning right.
Officer Steinkamp testified that the marijuana odor was “burnt marijuana” based
on his “training and experience.” Id. at 43; see also id. at 51 (confirming that he
“believed it was burning marijuana [that he] smelled”); id. at 53 (stating that the
officers “started smelling marijuana”). Officer Minnehan likewise testified that he
believed he “was smelling burnt marijuana.” Id. at 65; see also id. at 71 (confirming
that he “smelled what [he] believed to be burning marijuana” “shortly after [the squad
car] turned north”); id. at 73 (confirming that he “smelled burnt marijuana”); id. at 76
(“I believe I was smelling burnt marijuana.”). Officer Garrett’s statements captured on
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video footage “indicate that he[,] too[,] believed he smelled burnt marijuana.” R. Doc.
49, at 4 (citing Gov’t’s Ex. 2-C, at 17:58–18:02).
The officers changed lanes and sped up to position the squad car close behind
the Impala in the left lane. A black truck was immediately in front of the Impala. An
SUV was farther ahead in the right lane. The road was busy at that time. The officers
drove directly behind the Impala “for several blocks”—approximately 30 seconds—to
“make sure that [they] kn[e]w for certain without a shadow of a doubt that [it was the]
vehicle that has the odor of marijuana emitting from it.” R. Doc. 38, at 40. “[T]he odor
of marijuana remained constant” after the officers followed the Impala “for several
more blocks.” Id. at 64. The officers could see inside the Impala while following
behind it and never saw smoke inside the car or coming out of the car. Nonetheless,
based on the smell of “burnt marijuana,” the officers “believe[d] that somebody in the
car was actively smoking marijuana.” Id. at 65. As a result, the officers decided to
conduct a traffic stop of the Impala and activated the squad car’s lights. The Impala
pulled over to the side of the road.
The officers continued to smell marijuana emanating from the Impala after the
stop. Officer Steinkamp, while preparing to exit the squad car, commented that “[i]t
still reeks of weed.” Id. at 28. Officer Steinkamp testified that the marijuana odor grew
“[s]tronger” as he approached the Impala. Id. at 31. Officer Minnehan testified that
“[w]hen [he] got close to the vehicle, [he] could clearly detect [the smell of marijuana]
coming strongly from inside the vehicle.” Id. at 65. Officer Garrett testified that “[a]s
[he] approached the passenger’s side of the vehicle, [he] could still smell the odor of
marijuana.” Id. at 83.
Officers Steinkamp and Minnehan went to the Impala’s driver’s side. Officer
Garrett went to the Impala’s passenger’s side. Officer Garrett saw a digital scale in the
pouch behind the passenger’s seat. Officer Steinkamp directed Shumaker to step out
of the car. Shumaker complied. Officer Minnehan asked Shumaker, “Do you got a
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bunch of weed in here, or were you just smoking and driving?” R. Doc. 49, at 5
(quoting Gov’t’s Ex. 1, at 1:45–1:47). Shumaker responded, “Nah, just smoking. Not
too long ago though.” Id. (quoting Gov’t’s Ex. 1, at 1:48–1:49). Officer Steinkamp
then asked, “Smoking weed?” Id. (quoting Gov’t’s Ex. 1, at 1:50–1:51). Officer
Minnehan commented, “As we were behind you, it reeks like weed.” Id. at 6 (quoting
Gov’t’s Ex. 1, at 1:50–1:52). Shumaker denied smoking marijuana in the car. Officer
Minnehan then stated, “I can still smell it.” Id. (quoting Gov’t’s Ex. 1, at 1:55–1:56).
Shumaker responded, “Yeah.” Id. (quoting Gov’t’s Ex. 1, at 1:56–1:57). Officer
Minnehan inquired if there was anything illegal in the car. Shumaker answered that
his girlfriend’s gun was in the vehicle.
Officer Steinkamp handcuffed Shumaker and moved him to the squad car, while
Officers Garrett and Minnehan searched the Impala. Upon his entry into the vehicle,
Officer Garrett continued to smell a marijuana odor, commenting, “It’s strong,” to
which Officer Minnehan replied, “It is.” Appellee’s Br. at 5 (quoting Gov’t’s Ex. 3,
at 3:08–16). Officer Minnehan saw a closed-container ashtray in the front seat’s
cupholder. The ashtray had a lid with a small hole in the center; its contents were not
visible. Officer Minnehan removed the lid and found several partially smoked
marijuana cigarettes and ash. Officer Minnehan identified a “larger piece [that did] not
have any ash on it. It[] [was] sitting on top of all the ashes.” R. Doc. 38, at 69. Officer
Minnehan observed that “the paper it[] [was] wrapped in [appeared] fresher than all
the other ones.” Id. Officer Minnehan commented to Officer Garrett, “Oh here you go,
Garrett. He was smoking and driving.” R. Doc. 49, at 6 (quoting Gov’t’s Ex. 3, at
3:28–3:32). Officer Minnehan then exited the Impala and advised Officer Steinkamp,
“There’s a blunt half full of weed in there. He was definitely smoking and driving.”
Id. (quoting Gov’t’s Ex. 3, at 3:56–4:01).
In addition to the marijuana cigarettes, the officers also recovered a digital scale
with trace amounts of marijuana residue on it and a loaded nine-millimeter pistol in
the center console. They did not find embers or smoke in the ashtray or a lighter.
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While Officers Garrett and Minnehan searched the Impala, Officer Steinkamp
stayed with Shumaker in the squad car. Shumaker denied smoking and driving. In
response, Officer Steinkamp stated, “While I was behind you, all three of us, we could
smell it.” Id. (quoting Gov’t’s Ex. 1, at 4:03–4:07). Shumaker responded, “I wasn’t
smoking and driving though.” Id. (quoting Gov’t’s Ex. 3, at 4:08–4:09). According to
Shumaker, he had smoked marijuana before leaving his house but was not smoking
while driving. After several minutes passed, Shumaker again insisted that he did not
smoke and drive. Officer Steinkamp remarked, “Say what you want, but we know
what we smelled.” Id. at 6–7 (quoting Gov’t’s Ex. 3, at 9:55–9:58). Shumaker retorted,
“You can smell it all you want, but there’s no smoke in the car.” Id. at 7 (quoting
Gov’t’s Ex. 3, at 9:59–10:01). Officer Steinkamp replied, “But that marijuana blunt
inside the car?” Id. (quoting Gov’t’s Ex. 3, at 10:02–10:03). Shumaker answered that
the marijuana roaches were old.
Officer Steinkamp exited the squad car and placed his notepad on the car’s hood
while awaiting the results of Shumaker’s criminal history check. Video footage shows
the wind blowing the pages of the notepad toward the car’s windshield. Based on the
pages’ movement, Officer Steinkamp testified that the wind was “blowing upwards
from the north to the south direction.” R. Doc. 38, at 36; see also id. at 37 (testifying
that wind was blowing “[n]orth to south”). Officer Minnehan “believe[d] the wind was
kind of swirling a little bit that day” but noted that “several times the paperwork was
blowing as the wind was blowing north to south.” Id. at 76–77.
Officer Garrett also spoke with Shumaker in the squad car. Shumaker stated to
Officer Garrett that he had not smoked in the car; instead, he had smoked right before
getting into the car. After a few minutes, Officer Garrett commented, “So that roach
was not from today? Because it sure was strong.” R. Doc. 49, at 7 (quoting Gov’t’s Ex.
2-C, at 17:58–18:02). Shumaker answered, “No, bro. I smoke strong weed, that’s
why.” Id. (quoting Gov’t’s Ex. 2-C, at 18:02–18:05).
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B. Procedural History
Based on the firearm found in the Impala, Shumaker was charged with 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). Shumaker moved to suppress all
evidence derived from the traffic stop.
At the suppression hearing, the officers testified consistently with the fact
recitation above. Additionally, both parties introduced expert testimony concerning
the officers’ ability to smell marijuana emanating from Shumaker’s car while driving
behind him. Dr. Richard L. Doty, the Director of the Smell and Taste Center at the
University of Pennsylvania Medical Center testified as Shumaker’s expert. Dr. Doty
testified about his research projects concerning raw marijuana.2 Thereafter, he testified
that, based on his review of the evidence and his experience, the officers would have
been unable to smell the marijuana in Shumaker’s ashtray while driving behind him.
Dr. Doty reached his conclusion based on the “very small amount of marijuana”
recovered, the marijuana’s placement “inside a closed container inside an automobile,”
“the barriers inside a patrol car, the distances [between the vehicles], traffic,” “the
turbulence of the other cars, [and] the wind direction.” R. Doc.38, at 98–99. As to the
wind direction, Dr. Doty relied on local weather reports in testifying that the wind on
the day of the stop was blowing “west to east—south—west to southeast.” Id. at 98.
Dr. Doty also opined that the officers could not have smelled a marijuana odor
coming from Shumaker’s vehicle even if Shumaker had smoked the marijuana before
entering his vehicle, had smoked in his vehicle prior to driving, or had smoked while
driving in front of the officers. Dr. Doty’s conclusions were again based on the
2For example, Dr. Doty testified that in one double-blind study, a bag of
marijuana was placed in the back of a vehicle during some trials, while in other trials
newspaper was placed in the back of the vehicle. Dr. Doty determined “that under
those circumstances you could not smell marijuana outside an automobile.” R. Doc.
38, at 94–95.
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distance between the cars, the turbulence, the wind, and the officers’ placement in the
squad car.
Finally, Dr. Doty testified that the officers could not have pinpointed the source
of the odor even if they had smelled marijuana while driving behind Shumaker
because of the presence of other cars, the surrounding vegetation, and the wind. Dr.
Doty confirmed that his opinions were “all . . . to a reasonable degree of scientific
certainty.” Id. at 101.
On cross-examination, Dr. Doty conceded that “[u]nder some circumstances”
“the wind can carry molecules, making it easier to detect the smell.” Id. at 103. He
further admitted that because the wind “was highly variable [the] day [of the stop], it
could have been at times blowing out of the north directly towards the officers.” Id.
Additionally, he admitted that a marijuana odor may be stronger when it is being
smoked and that an odor’s strength “depend[s] on the strength of the marijuana.” Id.
at 106. Finally, he conceded that his experiments, on which his opinion rested, did not
“involve burning marijuana.” Id. at 109.
On re-direct, Dr. Doty reviewed weather records and testified that they indicated
that the wind was traveling “[w]est-northwest” on the day of the traffic stop. Id. at
112. He explained that the weather records “[m]ore or less” indicated that “the wind
[was] coming from the west and blowing to the east.” Id. at 112–13. “[I]n general,” he
explained, “when you smell something, you want to be downwind from it.” Id. at 113.
In rebuttal, David. L. Frye testified for the government. Frye is a former
Nebraska state trooper, “a part-time deputy with the Seward County Sheriff’s Office
in Nebraska, and . . . also a director of training for a law enforcement training
program called Desert Snow.” R. Doc. 62, at 7. “Desert Snow,” Frye explained, “is the
largest private provider of criminal interdiction training in the United States.” Id. at
12. As “the director of training,” Frye assembles training materials used by the
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instructors. Id. at 13. Desert Snow conducts “approximately 60 to 70 classes a year”
“in over 40 different states,” and Frye “teach[es] several of those” classes. Id. at
13–14. Frye is “also involved in teaching federal agencies.” Id. at 14.
Frye described his personal experience as an officer following vehicles and
detecting the smell of marijuana. As a patrol officer, Frye testified that he has made
“[o]ver 500” “stops . . . over the years.” Id. at 17. According to Frye, he has
“personally interdicted marijuana,” among other drugs. Id. He testified that, to identify
the marijuana odor’s source, he would follow cars and observe whether the odor
“stay[ed] consistent.” Id. at 18. If it did, then he would conclude that “the odor was
coming from” “the vehicle in front of [him].” Id. He would confirm his conclusion by
stopping the vehicle. Id. Additionally, in his role as director of training for Desert
Snow, Frye has “poll[ed] . . . officers across the United States [and learned] that there
are hundreds of officers that” “have smelled marijuana when . . . traveling behind a
car.” Id. at 20–21.
Having reviewed the video and other evidence in the case, Frye testified that
“[b]ased upon [his] training and experience . . . it [would] have been possible for [the]
officers to smell marijuana that was coming from [Shumaker’s] vehicle.” Id. at 22. He
“kn[e]w it[] [was] possible because [he had] experienced it on multiple occasions in
[his] own life and career.” Id. His opinion was also based on “the distance [the
officers] were traveling behind the vehicle”; “[t]he period of time or the length of time
that they traveled behind the vehicle”; and “[t]he conditions or the apparent conditions
based upon [his] observation of [the] tape,” “includ[ing] the wind.” Id. at 23–24. Frye
testified that a vehicle’s windows being up “would diminish the odors leaving the
vehicle,” although he noted that is “still possible to smell . . . if the windows are up”
“but not from a great distance.” Id. at 24.
Frye further opined that “at some point marijuana was being smoked in the
vehicle.” Id. at 22. He based his opinion on “the dash cam footage show[ing] other
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things that [he] commonly encounter[s] with individuals smoking marijuana inside of
vehicles.” Id. at 23. Specifically, the center console contained a cologne bottle and
deodorizer. According to Frye, he “[c]onstantly” encounters those items “as an
interdiction officer,” which are used for “[m]asking and deodorizing.” Id.
On cross-examination, Frye testified that officers must identify which car is
emitting the marijuana odor when driving behind multiple cars prior to making a
traffic stop. Additionally, he stated that officers must confirm which car is the source
of the odor when they smell marijuana while driving behind a car that is immediately
behind another car. According to Frye, strong winds moving against the traffic can
carry the marijuana odor a far distance. And, he explained, officers have a harder time
smelling a marijuana odor when a vehicle’s windows are rolled up. He admitted that
marijuana cigarettes are hard to smell if they are in a closed container and that none
of the marijuana cigarettes found in Shumaker’s ashtray appeared to be burning. But
he explained that he would not expect the marijuana cigarettes to be burning because
drivers smoking marijuana generally put the cigarette out as quickly as possible prior
to the traffic stop.
1. Credibility
The district court denied Shumaker’s suppression motion. First, the court found
that “the officers credibly testified that they smelled burnt marijuana while driving
behind Shumaker.” R. Doc. 49, at 1. The court’s conclusion was based “on the
officers’ demeanor while testifying, the content and consistency of the officers’
testimony, Frye’s expert testimony, and the video evidence from the stop
corroborating the officers’ testimony.” Id. at 13. The court did “not find the absence
of smoke, embers, and a lighter sufficiently probative to discredit the officers’
otherwise consistent and corroborated testimony.” Id. at 15. And, the court “credit[ed]
the testimony of Frye over the testimony of Dr. Doty on whether the officers could
have smelled burnt marijuana while driving behind Shumaker.” Id. In support, the
court cited “an important limitation on [Dr. Doty’s] testimony: None of the tests or
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experiments he performed on the human capacity to smell marijuana involved burnt
marijuana.” Id. And, the court noted, “Dr. Doty conceded that the smell of burnt
marijuana is ‘[p]resumably’ stronger than the smell of unburnt marijuana, and the
strength of the smell depends on the strength of the marijuana.” Id. (quoting R. Doc.
38, at 105, 106). The court found “a stronger basis for [Frye’s] testimony” “based on
his personal and professional experiences smelling the odor of burnt marijuana while
patrolling city streets.” Id.
The district court also rejected Shumaker’s reliance on State v. Williams, No.
SRCR328401 (Iowa Dist. Ct. Oct. 8, 2019), a case involving a state trial court’s
suppression of evidence resulting from Officers Minnehan and Steinkamp’s traffic
stop of a defendant’s vehicle “after smelling an odor of marijuana they believed was
coming from his car.” Id. at 16. Williams was distinguishable, the district court
explained, because “only Officer Minnehan testified, and he could not recall whether
he smelled raw or burnt marijuana.” Id. “[B]y contrast,” the court explained, “Officers
Steinkamp, Minnehan, and Garrett testified consistently that they smelled burnt
marijuana while driving behind Shumaker.” Id.
2. Particularized Suspicion
Second, the district court concluded that the officers had a reasonable,
particularized suspicion that the marijuana odor was emanating from Shumaker’s car,
as opposed to other cars in the vicinity. The court based its conclusion on the
“calculated steps” “the officers took . . . to confirm that the marijuana odor they
smelled came from Shumaker’s car.” Id. at 21. Specifically, all the officers testified
that they began “smelling burnt marijuana shortly after turning” and that “they ruled
out the black sedan as the source of the odor because they previously followed the
black sedan without smelling marijuana.” Id. Furthermore, the court noted, “[t]he
officers drove directly behind Shumaker for thirty seconds and continued to smell
marijuana during that time.” Id. at 21–22.
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The court rejected Shumaker’s arguments that the officers failed to rule out
other vehicles. The court explained that “the officers were not required to separately
follow the black truck driving in front of Shumaker to definitively rule it out as the
source of the odor” because “Shumaker’s car was directly in front of them” and “[t]he
black truck was farther away, separated from them by Shumaker’s car.” Id. at 22.
The court also rejected Shumaker’s argument that “the officers did not rule out
the black sedan because they failed to account for the change in wind after the turn.”
Id. The court found that “the wind evidence [was] inconclusive” and that it actually
“undercut[] Shumaker’s argument.” Id. at 23. While Officers Steinkamp and Minnehan
testified that “the wind was blowing north to south at the time in question,” “the
weather records and expert testimony Shumaker introduced contradict[ed]” this
evidence. Id. Specifically, “Dr. Doty testified based on the records that the wind was
blowing west-northwest around the time of the stop,” which “[m]ore or less” meant
that “the wind [was] coming from the west and blowing to the east.” Id. Crediting Dr.
Doty’s testimony, the court noted, would mean that “the wind was blowing against
traffic before the officers turned.” Id. “Based on Dr. Doty’s testimony that odors
generally travel downwind,” the court explained, “the officers would have been more
likely to smell marijuana coming from the black sedan before turning.” Id.
Similarly, the court rejected Shumaker’s argument that the officers “failed to
eliminate other cars on the road,” such as the “black SUV driving ahead of Shumaker
in the right lane.” Id. The court pointed out that the black SUV was “not visible on the
dash camera video when the officers beg[a]n following Shumaker, and it remain[ed]
well ahead of Shumaker until shortly before the officers ma[d]e the stop.” Id.
II. Discussion
Shumaker argues that the district court erred in denying his motion to suppress
evidence seized as a result of the traffic stop because (1) the officers’ testimony that
they smelled marijuana while driving behind him is incredible, and (2) the officers
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lacked a reasonable, particularized suspicion that the marijuana odor was emanating
from his vehicle, as opposed to other vehicles in the vicinity.
“On appeal from a denial of a motion to suppress, we review the district court’s
factual findings for clear error and review its legal conclusions de novo.” United States
v. Williams, 955 F.3d 734, 737 (8th Cir. 2020).
“The Fourth Amendment guarantees the right to be free from unreasonable
searches and seizures. Because a traffic stop is a seizure under the Fourth Amendment,
it must be supported by reasonable suspicion or probable cause.” Garcia v. City of
New Hope, 984 F.3d 655, 663 (8th Cir. 2021) (citation and internal quotation marks
omitted). “Reasonable suspicion exists when an officer is aware of particularized,
objective facts which, taken together with rational inferences from those facts,
reasonably warrant suspicion that a crime is being committed.” United States v.
Givens, 763 F.3d 987, 989 (8th Cir. 2014) (internal quotation marks omitted).
1. Credibility
Shumaker contends that the court clearly erred in crediting the officers’
testimony that they “could have smelled marijuana based upon less than a gram of
unlit marijuana roaches in a covered ash tray.” Appellant’s Br. at 14–15. Shumaker
argues that the officers’ claim was implausible and refuted by Dr. Doty’s testimony.
He further cites the state trial court’s rejection in Williams of Officer Minnehan’s
testimony that he and Officer Steinkamp smelled a small amount of marijuana in a
vehicle while they were driving their squad car.
Shumaker first contends that the district court clearly erred in concluding that
the officers could smell marijuana while trailing Shumaker’s car. The district court
found “that Officers Steinkamp, Minnehan, and Garrett credibly testified that they
smelled burnt marijuana while following Shumaker.” R. Doc. 49, at 13. The district
court’s factual finding was based “on the officers’ demeanor while testifying, the
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content and consistency of the officers’ testimony, Frye’s expert testimony, and the
video evidence from the stop corroborating the officers’ testimony.” Id.
“On appeal, we review those findings of fact for clear error, and so long as a
factual finding is based upon a coherent and facially plausible story that is not
contradicted by extrinsic evidence, that finding, if not internally inconsistent, can
virtually never be clear error.” United States v. Scott, 818 F.3d 424, 428 (8th Cir.
2016) (internal quotation marks omitted). The question is not “[w]hether we would
come to the conclusion in the first instance that [the officers] smelled [marijuana]”
while driving behind Shumaker’s vehicle. Id. at 429. Instead, the question is whether
“the district court’s factual findings [must] be set aside [in light of] the deference we
owe them.” Id. (citing United States v. Wright, 512 F.3d 466, 471 (8th Cir. 2008)
(“[T]he [district] court’s credibility determinations require a high degree of
deference.”)).
Having reviewed the record, we hold that the district court’s factual finding that
the officers credibly testified to smelling burnt marijuana while driving behind
Shumaker is not clearly erroneous. The district court’s credibility finding was based
on (1) the consistency of the officers’ testimony, (2) the corroborating evidence, and
(3) Frye’s expert testimony. First, the officers consistently testified to smelling burnt
marijuana shortly after turning behind Shumaker’s open-windowed Impala. They had
not previously noticed the odor when following the close-windowed black sedan. The
officers consistently testified that they followed the Impala and that the odor
“remained constant,” leading to their conclusion that the Impala’s occupant was
smoking and driving. R. Doc. 38, at 64.
Second, video evidence corroborated the officers’ testimony that they smelled
marijuana. As the district court explained:
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Videos of the stop show the officers making statements both before and
during the stop indicating they smelled burnt marijuana coming from
Shumaker’s car while driving behind him. Shumaker does not respond
to these statements with surprise or doubt. Instead, he insists he smoked
before driving, and not while driving. At one point, he even explains that
the officers could smell his marijuana because it was “strong weed.” The
officers’ testimony is further corroborated by the marijuana roaches
recovered from Shumaker’s car—one of which was larger and fresher
than the others—and the cologne bottle and deodorizer near the ashtray.
R. Doc. 49, at 13–14 (citations omitted).
Third, the district court explained why it “credit[ed] the testimony of Frye over
the testimony of Dr. Doty on whether the officers could have smelled burnt marijuana
while driving behind Shumaker.” Id. at 15. Notably, Dr. Doty admitted that “[n]one
of the tests or experiments he performed on the human capacity to smell marijuana
involved burnt marijuana,” while Frye testified “based on his personal and
professional experiences smelling the odor of burnt marijuana while patrolling city
streets.” Id. Dr. Doty also conceded that burnt marijuana’s smell is “[p]resumably”
stronger than unburnt marijuana’s smell. Id. (alteration in original) (quoting R. Doc.
38, at 105, 106).
The district court also sufficiently explained its rejection of “Shumaker’s
counterarguments.” Id. at 14. For example, the district court explained that “the lack
of evidence of smoke, embers, and a lighter does not discredit the officers’ testimony”
that they smelled burnt marijuana because the officers found “several marijuana
roaches in Shumaker’s car. And Officer Minnehan testified that one of the roaches was
larger and fresher than the others.” Id. at 14–15. The court also credited Officer
Minnehan’s testimony “that it is not unusual to drive behind a person who is smoking
without seeing smoke” “because Shumaker’s windows were open.” Id. at 15. And Frye
testified “that marijuana was smoked in Shumaker’s car at some point” “based on the
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marijuana recovered, the cologne bottle, and the deodorizer.” Id. According to Frye,
“he would not expect to find embers in the ashtray because individuals who smoke
while driving generally extinguish the smoke as soon as possible when they are pulled
over.” Id.
Finally, the district court sufficiently distinguished Williams in which a state
trial court did not credit Officer Minnehan’s testimony that he smelled marijuana
emanating from a vehicle. In that case, “only Officer Minnehan testified, and he could
not recall whether he smelled raw or burnt marijuana,” while in the present case
“Officers Steinkamp, Minnehan, and Garrett testified consistently that they smelled
burnt marijuana while driving behind Shumaker” and their testimony was
“corroborated by their on-video statements, Shumaker’s behavior, Frye’s expert
testimony, and the evidence recovered from Shumaker’s car.” Id. at 16–17.
2. Particularized Suspicion
Alternatively, Shumaker argues that even if the officers smelled marijuana, they
did not have a reasonable, particularized suspicion that his vehicle was the source.
Reasonable suspicion requires “a particularized and objective basis for
suspecting the particular person stopped of criminal activity.” Navarette v. California,
572 U.S. 393, 396 (2014) (quoting United States v. Cortez, 449 U.S. 411, 417–18
(1981)). A “hunch” does not suffice, but the standard requires less suspicion than
probable cause and “considerably less than proof of wrongdoing by a preponderance
of the evidence.” Id. at 397 (citation and internal quotation marks omitted). The
ultimate determination is based on the totality of the circumstances. Id.
Here, Shumaker argues that the officers lacked a particularized suspicion
because “several other vehicles were near the patrol car at [the] time, including two
vehicles in front of Shumaker”; “[t]he officers only followed [his] vehicle for thirty
seconds”; the officers “did not wait to see if the smell continued when Shumaker
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turned onto another road”; and the wind conditions are a “possible explanation” for
why the officers did not smell marijuana until they turned and, therefore, the black
sedan cannot be ruled out as the source of the marijuana odor. Appellant’s Br. at
17–18.
While “[w]e have repeatedly held that the odor of marijuana provides probable
cause for a warrantless search of a vehicle under the automobile exception”3 and
declined “to distinguish between a faint smell and a strong smell [of marijuana] in
determining whether the marijuana odor is enough to prolong a stop,”4 we have not
directly addressed whether the odor of burnt marijuana justifies an officer’s stop of a
particular vehicle.
The Third Circuit, however, has addressed how particularized an officer’s
suspicions must be before stopping a car based on the odor of marijuana. See United
States v. Ramos, 443 F.3d 304, 306 (3d Cir. 2006). In Ramos, officers saw two cars
parked next to each other in a parking lot. Id. The officers drove their unmarked car
between the cars. Id. When one of the officers was three or four feet from the
defendant’s car, “he smelled ‘marijuana smoke’ through his open window.” Id. The
defendant’s window was partially open. Id. The officers stopped the defendant after
he drove away. Id. Upon searching the car, the officers found marijuana and guns. Id.
The defendant moved to suppress this evidence, and the district court granted the
motion. Id. at 307.
The Third Circuit reversed, holding that the officers had reasonable suspicion
to stop the defendant’s car. Id. at 309. The court explained:
3United States v. Williams, 955 F.3d 734, 737 (8th Cir. 2020).
4United States v. Smith, 789 F.3d 923, 929 (8th Cir. 2015).
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In the abstract, the defendants may be correct that, at some point,
a broadly diffuse and undistinguished marijuana odor will not
automatically provide the necessary particularity to establish reasonable
suspicion. For instance, had the officers smelled marijuana odor in a
crowded bar, they would not be justified to pat down every patron on the
claim of some individualized reasonable suspicion. See Ybarra v. Illinois,
444 U.S. 85, 100 S. Ct. 338, 62 L. Ed. 2d 238 (1979). But defendants’
claim that reasonable suspicion requires the same level of particularity
as probable cause is misguided. See United States v. French, 974 F.2d
687, 692 (6th Cir. 1992) (holding that reasonable suspicion existed to
stop defendants who had been riding in tandem with a truck that
possessed a marijuana odor).
To establish reasonable suspicion, the particularity requirement
need not be as stringent as it might be for probable cause. Thus, while
probable cause may require the odor to be particularized to a specific
person or place, in this case we are satisfied that the totality of the
circumstances sufficiently particularized the odor to justify a Terry stop
of the defendants’ car.
Id. (footnote omitted).
Based on the totality of the circumstances, the court determined that “it would
have been reasonable for the officers to conclude that the odor was coming from one,
the other, or both vehicles” and that such “probability establishe[d] the odor as
sufficiently particularized.” Id. As a result, “it was likewise reasonable for the
officers[] to suspect that criminal activity was afoot.” Id.
The present case resembles Ramos. “[T]he totality of the circumstances
sufficiently particularized the odor to justify a Terry stop of [Shumaker’s] car” based
on the facts identified by the district court. Id. Specifically, when the officers first
perceived the smell of burnt marijuana, the two cars closest to the officers’ vehicle
were the black sedan and Shumaker’s vehicle. There was no oncoming traffic at that
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time; the road was one-way. The officers testified that they eliminated the black sedan
as the source of the odor because they previously followed the black sedan without
smelling marijuana; furthermore, Officer Garrett testified that the black sedan’s
windows were up. The officers drove directly behind Shumaker for 30 seconds and
continued to smell marijuana during that time. Shumaker’s car windows were down,
and the scent of burnt marijuana “remained constant” as the officers followed
Shumaker’s vehicle. R. Doc. 38, at 64.
The district court did not err in denying Shumaker’s motion to suppress.
III. Conclusion
Accordingly, we affirm the judgment of the district court.
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