United States of America v. Tommy Collier

United States Court of Appeals
For the Eighth Circuit
___________________________
No. 23-3255
___________________________
United States of America
Plaintiff - Appellee
v.
Tommy Collier
Defendant - Appellant
____________
Appeal from United States District Court
for the Eastern District of Arkansas - Central
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Submitted: April 9, 2024
Filed: September 6, 2024
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Before SMITH, WOLLMAN, and GRASZ, Circuit Judges.
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SMITH, Circuit Judge.
A jury found Tommy Collier guilty of unlawfully possessing cocaine with
intent to distribute, in violation of 21 U.S.C. § 841. On appeal, Collier raises several
issues. On all issues, we affirm the judgment of the district court.1
1 The Honorable D.P. Marshall Jr., then Chief Judge, now United States
District Judge for the Eastern District of Arkansas.

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I. Background
While patrolling Interstate 40 in Lonoke County, Arkansas, State Police
Corporal Travis May saw a motorist drift into the shoulder. He initiated a traffic
stop. May walked up to the car, greeted the motorist, and asked if he was “doing
okay.” Gov’t Ex. 2, at 1:44. May noticed that the motorist’s “hands were shaking
pretty uncontrollably” and that the car interior had a “lived-in look” with “lots of
trash” and “signs of hard travel.” R. Doc. 125, at 34. The motorist, Collier, was a
resident of Greenville, Mississippi, and he was driving a car rented in Las Vegas,
Nevada, with a Utah license plate. May asked Collier about his travel plans. Collier
said that he drove from Mississippi to Little Rock, Arkansas, to shop for tires.
Collier’s shaking hands, disorderly car interior, and unusual itinerary aroused May’s
suspicion.
May believed further inquiry was warranted. He asked Collier if he had any
weapons or drugs in the car. Collier replied that he did not. May took Collier’s
driver’s license back to the patrol vehicle. He ran a routine warrant check, which
came back clear. When May returned to Collier’s car, he asked Collier for
permission to conduct a search. Collier declined. May then told Collier to wait
because he was calling a K-9 unit to the traffic stop.2
The K-9 unit, consisting of Arkansas State Police Sergeant Mark Blackerby
and the drug-detection dog Raptor, arrived about four minutes later. Blackerby
explained to Collier that he would run Raptor around the car, and if Raptor smelled
drugs, Blackerby and May would have probable cause to conduct a search.
Blackerby ran Raptor around the car. Raptor smelled drugs and alerted to their
presence. However, Raptor was unable to pinpoint the drugs’ exact location. May
2 On appeal, Collier does not make, and therefore waives, any argument that
May unreasonably prolonged the traffic stop. See United States v. Cooper, 990 F.3d
576, 583 (8th Cir. 2021) (“Ordinarily, a party’s failure to make an argument in [his]
opening brief results in waiver of that argument.”).

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and Blackerby proceeded with a search. They found a small amount of marijuana
intermingled with Collier’s personal belongings. More importantly, they recovered
ten bundles of white powder, which appeared to be cocaine. They arrested Collier.
Authorities later determined that the bundles contained about 10.08 kilograms
of white powder. Powder from two bundles field-tested positive for cocaine. The
bundles were sent to the Arkansas State Crime Laboratory for further analysis. The
laboratory’s analysis confirmed that the powder was cocaine.
The federal government obtained a one-count indictment against Collier for
unlawful possession of cocaine with intent to distribute, in violation of 21 U.S.C.
§ 841(a)(1) and (b)(1)(A). Collier pleaded not guilty, and the case proceeded to trial.
The jury found Collier guilty. The district court subsequently imposed a statutory
minimum sentence of ten years’ imprisonment. Collier appeals.
II. Discussion
On appeal, Collier raises six principal issues. We address these issues in the
order that he presents them. On all six issues, we affirm.
A. Reliability of the Drug-Detection Dog
First, Collier challenges the reliability of the canine, Raptor, to satisfactorily
detect illicit drugs. He also contends that Raptor’s alert was insufficient to establish
probable cause to search Collier’s car. See U.S. Const. amend. IV (recognizing “[t]he
right of the people to be secure in their persons, houses, papers, and effects, against
unreasonable searches and seizures . . . [without] probable cause”).
“We review de novo the district court’s legal determination of probable
cause.” United States v. Perez, 29 F.4th 975, 986 (8th Cir. 2022) (quoting United
States v. Gonzalez, 781 F.3d 422, 429 (8th Cir. 2015)). A dog is presumptively
reliable at detecting illicit drugs—and its alert establishes probable cause for a
search—if the dog has satisfactorily completed a bona fide certification or training
program. Florida v. Harris, 568 U.S. 237, 246–47 (2013). “This presumption may

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be overcome if a defendant can show” by cross-examination or opposing evidence
“the inadequacy of [the] certification or training program or that the circumstances
surrounding a canine alert undermined the case for probable cause.” Perez, 29 F.4th
at 986 (quoting Gonzalez, 781 F.3d at 429).
We reject Collier’s challenge to Raptor’s reliability. Before encountering
Collier’s car, Raptor completed a 320-hour basic training course under the Arkansas
State Police. Collier concedes that Raptor maintained its drug-detection skills
through “coordinated monthly sessions.” Appellant’s Br. at 11. The record contains
no opposing evidence undermining Raptor’s reliability. The record shows that
authorities had previously deployed Raptor 158 times, it had alerted 73 times, and
authorities had discovered illicit drugs 71 times. In the field, Raptor’s accuracy rate
was 97 percent. Our cases hold that, absent contradictory circumstances, a trained
dog’s alert will establish probable cause when the dog’s previous in-field accuracy
rate exceeds 50 percent. See United States v. Holleman, 743 F.3d 1152, 1157 (8th
Cir. 2014) (57 percent); United States v. Donnelly, 475 F.3d 946, 955 (8th Cir. 2007)
(54 percent). Raptor far surpassed our circuit’s 50-percent standard.3
Collier also questions how Raptor alerted,4 suggesting that its alert was
insufficiently “profound.” Appellant’s Br. at 2, 12. Our “probable cause inquiry is
always fact specific.” United States v. Tuton, 893 F.3d 562, 571 (8th Cir. 2018).
Every dog is unique, and a dog that smells illicit drugs is not required to
communicate with its handler in any specific way. See Holleman, 743 F.3d at 1156.
“Dogs alert in many different manners. One dog may alert in one manner while
3 That is not to say that a dog with less than 50-percent accuracy is useless.
The court evaluates a dog-sniff case, like any other probable-cause case, “under the
totality of the circumstances.” Donnelly, 475 F.3d at 954. Thus, the alert of a low-
accuracy dog, together with other circumstances that indicate the presence of illicit
drugs, can establish probable cause for a search. See id. at 954–55.
4See R. Doc. 79, at 8, 11 (discussing how Raptor “completely change[d]
directions” and “d[id] a 180” when it “smelled something”).

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another dog may alert in another manner.” United States v. Howard, 448 F. Supp.
2d 889, 898 (E.D. Tenn. 2006), aff’d, 621 F.3d 433 (6th Cir. 2010). The reliability
of a dog’s alert, not its manner, is what matters. See Holleman, 743 F.3d at 1156
(“Fourth Amendment jurisprudence does not require drug dogs to abide by a specific
and consistent code in signaling their sniffing of drugs to their handlers.” (quoting
United States v. Clayton, 374 F. App’x 497, 502 (5th Cir. 2010) (unpublished per
curiam))). Based on the record, we conclude that Raptor’s own unique manner of
alert reliably signaled the probable presence of illicit drugs.
Because Raptor was reliable and its alert was sufficient, Blackerby and May
had probable cause to search Collier’s car. The district court correctly admitted the
narcotics evidence derived from the search.
B. Admission of the Dog-Training Expert
Second, Collier argues that the district court erred when it permitted Major
Roby Rhoads, the K-9 coordinator for the Arkansas State Police, to give expert
testimony at a suppression hearing about the Arkansas State Police’s dog-training
program. Specifically, Collier argues that Rhoads was unqualified because Rhoads
was unaware that police dog training originated in the German “State of Northrine-
Westfalia” (North Rhine-Westphalia), he could not pronounce or translate the
German word “Polizeispurhundprüfung,” and he was unfamiliar with the history of
the International Congress of Police Service Dogs. Appellant’s Br. at 8–9.5
“We review the decision of the district court to admit expert testimony for an
abuse of discretion, giving substantial deference to the district court.” United States
5 Collier’s opening brief attacks Rhoads’s expertise for several pages, but it
does not specifically state what the district court should have done. Here, we will
assume that Collier argues for Rhoads’s exclusion. We will further assume without
deciding that Daubert applies to suppression hearings. See generally Daubert v.
Merrell Dow Pharms., Inc., 509 U.S. 579 (1993) (interpreting Fed. R. Evid. 702).
But see United States v. Ozuna, 561 F.3d 728, 737 (7th Cir. 2009) (“[T]he primary
rationale behind Daubert is not applicable in a suppression hearing.”).

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v. Primm, 63 F.4th 1186, 1190 (8th Cir. 2023). An expert is qualified if he has
“knowledge, skill, experience, training, or education” that will enable him to give
helpful testimony. See Fed. R. Evid. 702 (listing specific requirements). An expert’s
expertise must be “relevant to the task at hand.” Daubert, 509 U.S. at 597. A court
should not concern itself with a proposed expert’s knowledge, skill, experience,
training, or education in extraneous and irrelevant matters. See Fed. R. Evid. 402
(“Irrelevant evidence is not admissible.”).
Here, Collier’s challenge to Rhoads’s expert testimony lacks merit. Rhoads’s
ignorance of certain obscure facts related to police dog training did not discredit his
otherwise unobjected-to training and experience in the field. The geographic origin,
etymology, and history of police dog training are not relevant to the manner and
efficacy of the Arkansas State Police’s current program. The district court did not
abuse its discretion by permitting Rhoads to give expert testimony.
C. Standard for a Motion to Suppress
Third, Collier argues that the district court legally erred when it ruled on his
motion to suppress because it “utilized the wrong standard for suppression.”
Appellant’s Br. at 11 (cleaned up). Specifically, Collier argues that the court used a
“reasonable officer” standard and that it should have used a “reasonably prudent
person” standard or a “reasonable person” standard. Id. at 12–13. The question of
the appropriate standard for a motion to suppress is a question of law that we review
de novo. See United States v. Mallari, 334 F.3d 765, 766 (8th Cir. 2003).
In the Fourth Amendment context, the terms “reasonable officer,” “reasonably
prudent person,” and “reasonable person” are functionally equivalent. We have used
these terms interchangeably. See, e.g., United States v. Vittetoe, 86 F.4th 1200, 1203
(8th Cir. 2023); United States v. Lewis, 864 F.3d 937, 946–47 (8th Cir. 2017); United
States v. Anderson, 674 F.3d 821, 826–27 (8th Cir. 2012). Other circuits have done
the same. See, e.g., Edmond v. United States, 899 F.3d 446, 453–54 (7th Cir. 2018);
United States v. Martin, 613 F.3d 1295, 1301 (10th Cir. 2010) (Gorsuch, J.); United
States v. Ibarra, 345 F.3d 711, 716 (9th Cir. 2003). And the Supreme Court has used

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each of these terms—and many similar terms—with no indication that it intended to
impose an unalterable formulation. See, e.g., Plumhoff v. Rickard, 572 U.S. 765, 777
(2014) (“reasonable police officer”); Harris, 568 U.S. at 248 (“reasonably prudent
person”); Maryland v. Pringle, 540 U.S. 366, 372 (2003) (“reasonable officer”);
Florida v. Jimeno, 500 U.S. 248, 251 (1991) (“reasonable person”); Maryland v.
Buie, 494 U.S. 325, 332 (1990) (“reasonably prudent officer”); Brinegar v. United
States, 338 U.S. 160, 175 (1949) (“reasonable and prudent men”); Johnson v. United
States, 333 U.S. 10, 14 (1948) (“reasonable men”); Carroll v. United States, 267
U.S. 132, 162 (1925) (“a man of reasonable caution”); Stacey v. Emery, 97 U.S. 642,
645 (1878) (“a man of prudence and caution”).
Based on our review of the Fourth Amendment case law, we reject Collier’s
argument that reversal is required here because the district court’s denial of his
motion to suppress did not use a specific phrase. The district court’s evaluation was
clearly one of reasonableness. An evaluation for reasonableness, in light of the
totality of the circumstances, is all the case law requires. See Brigham City v. Stuart,
547 U.S. 398, 403 (2006) (calling “reasonableness” the Fourth Amendment’s
“ultimate touchstone” (internal quotation marks omitted)); Illinois v. Gates, 462 U.S.
213, 230–32 (1983) (holding that the Fourth Amendment analysis turns on common
sense or practical judgment, not technicalities).
D. Rule 16(a) Disclosures
Fourth, Collier argues that the government violated Federal Rule of Criminal
Procedure 16(a)(1)(G) by providing inadequate expert disclosures about Senior
Forensic Chemist Dan Hedges of the Arkansas State Crime Laboratory before
Hedges testified at trial. Thus, Collier contends that the district court should have
excluded Hedges or else limited the scope of his testimony.
“We review the decision of the district court to admit expert testimony for an
abuse of discretion, giving substantial deference to the district court.” Primm, 63
F.4th at 1190. “A defendant asserting reversible error under Rule 16(a)(1)(G) must
demonstrate prejudice resulting from the district court’s decision to admit the

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contested testimony.” United States v. Waln, 916 F.3d 1113, 1115 (8th Cir. 2019)
(quoting United States v. Kenyon, 481 F.3d 1054, 1062 (8th Cir. 2007)). Prejudice
exists when the government’s failure to make adequate disclosures unfairly surprises
the defendant, see Fed. R. Crim. P. 16 advisory committee’s note to 1993
amendment, or deprives the defendant of “a fair opportunity to prepare to cross-
examine [the] expert witness[] and secure opposing expert testimony if needed,” id.
advisory committee’s note to 2022 amendments; see McClendon v. United States,
587 F.2d 384, 388–89 (8th Cir. 1978) (stating that prejudice exists when the
government surprises the defendant and thereby prevents him from “conduct[ing] a
thorough cross-examination of each of the government witnesses at the trial”).
Here, the government provided Collier’s counsel with copies of Hedges’s
curriculum vitae and laboratory analysis in December 2022, well in advance of
Collier’s August 2023 trial. Collier’s counsel waited until trial to challenge these
disclosures, arguing that “[w]e are unsure if they are complete.” R. Doc. 126, at 100.
The district court asked counsel whether he sought to exclude Hedges, and he replied
that he “believe[d]” so. Id. at 102. The court reminded counsel that it had given the
parties a deadline, “21 days before trial,” for moving to exclude a witness. Id. at 107.
Collier’s counsel could not provide a “sufficient response” for why he missed the
court’s deadline. Id. at 108 (quoting the court). The court ruled that Collier would
suffer “no prejudice . . . by allowing the expert to testify.” Id. at 120. The court
stated, “[M]y scheduling order means what it says.” Id.
Assuming without deciding that the government’s expert disclosures about
Hedges were inadequate (an issue the parties dispute in their briefs), Collier suffered
no prejudice for three reasons. First, the government made its disclosures more than
seven months before trial—“a point in time early enough to avoid any possibility of
prejudice resulting from surprise.” McClendon, 587 F.2d at 388. Collier’s defense
had ample time to seek additional disclosures if it thought they were necessary.
Second, given how far in advance the government made its disclosures, Collier’s
defense had “a fair opportunity to prepare to cross-examine [Hedges] and secure
opposing expert testimony if needed.” Fed. R. Crim. P. 16 advisory committee’s

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note to 2022 amendments. Third, Collier’s motion to exclude Hedges’s testimony
was untimely, and a district court is justified in enforcing its reasonable deadlines.
See Fed. R. Crim. P. 12(c)(3) (“If a [defendant] does not meet the [district court’s]
deadline for making a [Rule 16 discovery] motion, the motion is untimely.”); United
States v. Trobee, 551 F.3d 835, 838 (8th Cir. 2009) (“Courts have a legitimate
interest in the enforcement of scheduling deadlines, both to manage a pending case
and to retain the credibility of these deadlines in future cases.”).
In other words, when the government makes its expert disclosures early and
the defendant brings his motion late, the district court does not abuse its discretion
by denying the defendant’s untimely motion. See Fed. R. Crim. P. 12(c)(3). Even if
the government’s Rule 16(a)(1)(G) disclosures are inadequate, a defendant suffers
no prejudice when his failure to request additional disclosures or prepare for cross-
examination is the result of his own neglect. Like the district court, we discern no
prejudice against Collier. When the court denied Collier’s untimely motion and
admitted Hedges as an expert witness, it acted within its discretion.
In addition, Collier contends that the government should have made expert
disclosures for Sergeant Blackerby, who testified about Raptor’s alert at the traffic
stop. The court ruled that Blackerby could testify as a lay witness, with no expert
disclosures, because his testimony was not “in the realm of real expert testimony.”
R. Doc. 126, at 45–48. Collier appeals the court’s ruling but provides no case law to
support his argument. See Appellant’s Br. at 16–17. The government replies that the
handler of a drug-detection dog may testify as a lay witness and that, consequently,
expert disclosures are not required. See Appellee’s Br. at 27–28.
Whether the officer who handles a drug-detection dog is an expert witness,
for whom expert disclosures are required, or a lay witness, for whom expert
disclosures are not required, appears to be an issue of first impression in our court.
The Supreme Court has not spoken clearly on this issue. See Harris, 568 U.S. at 247
(“A defendant . . . must have an opportunity to challenge such evidence of a dog’s
reliability, whether by cross-examining the testifying officer or by introducing his

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own fact or expert witnesses.” (emphases added)). And among our sister circuits,
only the First Circuit seems to have addressed the issue. See United States v.
Naranjo-Rosario, 871 F.3d 86, 96–97 (1st Cir. 2017) (holding that officers who
handle drug-detection dogs are expert witnesses).
We need not answer the question here. Regardless of Blackerby’s expert or
lay status, Collier has not “demonstrate[d] prejudice” due to the absence of expert
disclosures. Waln, 916 F.3d at 1115 (quoting Kenyon, 481 F.3d at 1062); cf. United
States v. Mackey, 83 F.4th 672, 677 (8th Cir. 2023) (rejecting a defendant’s
“conclusory argument” about an expert witness’s professional experience). Collier
has not shown that he was surprised when the government called Blackerby to
testify. See McClendon, 587 F.2d at 388; R. Doc. 69 (identifying Blackerby as a
government witness in June 2023). He also has not shown that he lacked “a fair
opportunity to prepare to cross-examine [Blackerby] and secure opposing expert
testimony if needed.” Fed. R. Crim. P. 16 advisory committee’s note to 2022
amendments. Thus, we affirm the district court’s admission of Blackerby’s
testimony without expert disclosures.
E. Cocaine Isomer Defense
Fifth, Collier raises a non-meritorious technical defense known as the
“cocaine isomer defense.” See United States v. Francesco, 725 F.2d 817, 820 n.1
(1st Cir. 1984) (collecting cases from eight circuits). This defense maintains “that
the chemical identification tests used by the government [cannot] adequately
distinguish between allegedly legal and concededly illegal forms of cocaine” and,
therefore, that prosecutions for cocaine possession “must fail for want of proof.”
United States v. Ortiz, 610 F.2d 280, 281 (5th Cir. 1980) (per curiam).
Specifically, Collier concedes that federal law bans “cocaine, its salts, optical
and geometric isomers, and salts of isomers,” 21 U.S.C. § 841(b)(1)(A)(ii)(II)
(emphasis added), but he argues that his ten bundles of white powder could have
contained a non-illicit, positional isomer of cocaine. At the district court, Collier
asserted that the government’s tests could not adequately distinguish between illegal

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cocaine and his purportedly legal positional isomer of cocaine. Collier requested a
special jury instruction on this defense, and he moved for a judgment of acquittal.
The court declined to give such an instruction, and it entered judgment on the jury’s
guilty verdict. These decisions were not erroneous.
Neither party identifies, nor have we located, a case from our circuit that is
directly on point. See United States v. Luschen, 614 F.2d 1164, 1168–70 (8th Cir.
1980) (rejecting a different version of the cocaine isomer defense that involved
different issues); see also United States v. Myers, 56 F.4th 595, 597–99 (8th Cir.
2022) (applying the categorical approach and comparing Missouri’s definition of
cocaine with the federal definition); United States v. Owen, 51 F.4th 292, 294–96
(8th Cir. 2022) (per curiam) (same with Minnesota’s definition); United States v.
Oliver, 987 F.3d 794, 807 (8th Cir. 2021) (same with Illinois’s definition). Rather,
we look to the First Circuit’s decision in United States v. Francesco, 725 F.2d 817.
We agree with the parties that Francesco is directly on point and persuasive. See
Appellant’s Br. at 18–19 (citing Francesco twice); Appellee’s Br. at 2, 30–31 (citing
Francesco as an apposite authority and again in the body of the brief).
In Francesco, federal agents seized a package “contain[ing] approximately
one kilogram of a white powdery substance identified as cocaine.” 725 F.2d at 819.
At his trial for possession with intent to distribute, the defendant argued that the
substance was not illegal cocaine but a legal cocaine isomer. Id. at 819–20. Based
on this argument, he requested a special jury instruction and moved for a judgment
of acquittal. Id. The district court ruled against the defendant on both points, the jury
returned a guilty verdict, and the court entered judgment accordingly. Id.
On appeal, the First Circuit affirmed. Id. at 820. It explained that there are
multiple isomers of cocaine, including (1) “narcotic” isomers,6 which are unlawful
to possess, and (2) non-narcotic isomers, which are chemically related but are not
6 In legal usage, the word “narcotic” may refer to any “drug that is controlled
or prohibited by law.” Narcotic, Black’s Law Dictionary (12th ed. 2024).

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themselves unlawful. Id. at 820–21. Despite this distinction, the First Circuit upheld
the conviction. Id. at 820. At trial, “government experts testified that the substances
seized from [the defendant] were ‘cocaine,’” and the defendant offered no evidence
to the contrary. Id. at 821. Accordingly, the First Circuit held:
The defendant’s failure to introduce evidence in support of his isomer
defense left the judge (whose instructions to the jury must be based on
the evidence adduced at trial) no choice but to instruct the jury that
cocaine is a Schedule II controlled substance. The jury then had no
alternative but to find that the substances identified as cocaine were
illegal forms of cocaine under the Drug Control Act. The instruction to
the jury was not erroneous and the jury was justified in finding the
defendant guilty of possession of a Schedule II controlled substance.
Id. at 821–22.
We adopt the First Circuit’s approach here. When the government produces
evidence that a defendant possessed illegal cocaine, the defendant is not entitled to
a special jury instruction on his cocaine isomer defense, unless he produces or points
to evidence that supports his position. See id. This rule accords with our circuit
precedent. See United States v. Morales, 684 F.3d 749, 756 (8th Cir. 2012) (“A
defendant is entitled to a particular jury instruction when the instruction [1] provides
a correct statement of the law and [2] is supported by the evidence.” (quoting United
States v. Harper, 466 F.3d 634, 649 (8th Cir. 2006))). And this rule does not relieve
the government of its burden to “prove every element of a crime beyond a reasonable
doubt.” Jones v. Hendrix, 599 U.S. 465, 487 (2023). The identity of a controlled
substance is always an element of the offense. See 8th Cir. Model Jury Instructions:
Criminal § 6.21.841A (2023) (requiring the government to prove that “the defendant
was in possession of (describe substance, e.g., cocaine)”).
Beyond a reasonable doubt, Collier’s jury expressly found that he possessed
“cocaine.” R. Doc. 95. Because his cocaine isomer defense was speculative and not

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supported by evidence, we hold that the district court did not abuse its discretion by
denying a special jury instruction. See United States v. Wright, 993 F.3d 1054, 1064
(8th Cir. 2021) (“We review jury instructions for an abuse of discretion.”).7
For similar reasons, we hold that the district court did not err when it denied
Collier’s motion for a judgment of acquittal. See United States v. Sainz Navarrete,
955 F.3d 713, 718 (8th Cir. 2020) (“We review the denial of a motion for judgment
of acquittal de novo.”). A judgment of acquittal, negating the jury’s guilty verdict,
“is warranted only when no reasonable jury could [have found] all the elements
beyond a reasonable doubt.” Wright, 993 F.3d at 1065 (quoting United States v.
Parsons, 946 F.3d 1011, 1014 (8th Cir. 2020)). Based on the evidence presented at
trial, a reasonable jury could have concluded that Collier’s bundles of white powder
were illegal cocaine rather than a non-narcotic cocaine isomer. See United States v.
Hall, 552 F.2d 273, 276 (9th Cir. 1977) (rejecting a cocaine isomer defense).
F. Curative Instruction
Sixth, during its closing argument, the government briefly commented on
Collier’s post-arrest, post-Miranda silence. See Miranda v. Arizona, 384 U.S. 436
(1966); R. Doc. 127, at 91 (“Mr. Collier said nothing.”). Collier moved for a mistrial,
and the district court denied his motion. The court offered to give a curative
instruction instead. Collier’s counsel replied, “We’ll leave it with the [c]ourt to do
what the [c]ourt thinks appropriate.” R. Doc. 127, at 98. The court advised the parties
of the instruction it would give, and Collier’s counsel replied, “Thank you, Your
7 Defendants may present evidence-free defenses. See United States v. Willis,
101 F.4th 577, 585 (8th Cir. 2024) (acknowledging that defendants have a right to
put forward “unorthodox defenses”); Gill v. Maciejewski, 546 F.3d 557, 564 (8th
Cir. 2008) (noting that “a criminal defendant has no burden to present evidence or
call witnesses” (emphasis omitted)). However, asserting an evidence-free defense
does not entitle the defendant to a special jury instruction. Morales, 684 F.3d at 756.
Instead, the defendant must try to raise reasonable doubt in the jurors’ minds within
the limits of the ordinary instructions. Here, Collier’s jury was free to entertain the
view that Collier possessed ten bundles of a non-narcotic cocaine isomer.

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Honor.” Id. at 98–99. Collier now challenges the denial of a mistrial and argues that
the jury instruction was insufficient to cure the Miranda violation.
Assuming without deciding that a Miranda violation occurred, we review for
abuse of discretion the district court’s denial of a motion for a mistrial. United States
v. Shield, 87 F.4th 883, 885 (8th Cir. 2023). “The prejudicial effect of any improper
[comment] is determined by examining the context of the error and the strength of
the evidence of the defendant’s guilt.” Id. (quoting United States v. Hollins, 432 F.3d
809, 812 (8th Cir. 2005)). Curative instructions are ordinarily preferable to mistrials
and “generally sufficient to alleviate prejudice.” United States v. Diaz-Pellegaud,
666 F.3d 492, 503 (8th Cir. 2012) (quoting United States v. Davidson, 122 F.3d 531,
538 (8th Cir. 1997)).
Upon our review of the trial transcript, we conclude that the government’s
comment on Collier’s post-Miranda silence was fleeting. See R. Doc. 127, at 91
(“Mr. Collier said nothing.”). The district court indicated that the jury might not have
noticed the comment and would not place weight on it. See id. at 98 (“I don’t want
to call undue attention to this and leaving it alone might well be the better practice.”).
Given the comment’s fleeting nature, the minor role that it played in the context of
the government’s much broader closing argument, and the weight of the evidence
against Collier, we hold that the district court did not abuse its discretion by giving
a curative instruction rather than granting a mistrial. Cf. United States v. Askew, 98
F.4th 116, 126 (4th Cir. 2024) (holding that a “fleeting reference” to a defendant’s
exercise of Miranda rights does not “constitute[] a per se due process violation”);
United States v. Reeves, 742 F.3d 487, 505 (11th Cir. 2014) (“[A] single,
inappropriate reference to a defendant’s post-arrest silence that is not mentioned
again is too brief to constitute a Fifth Amendment violation.”).
Turning to the curative instruction’s content, we note that Collier’s counsel
thanked the district court and did not object, so we review for plain error. See United
States v. Refert, 519 F.3d 752, 756 (8th Cir. 2008). “Plain error only exists if (1)
there was an error, (2) the error was plain, (3) the error affected [Collier’s]

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substantial rights, and (4) a failure to grant relief would seriously affect the fairness,
integrity, or public reputation of judicial proceedings.” Id. (quoting United States v.
Falcon, 477 F.3d 573, 577 (8th Cir. 2007)). Collier “fail[s] to show any error [in the
instruction], let alone error that was plain.” United States v. Rodriguez, 984 F.3d
704, 711 (8th Cir. 2021). Therefore, we affirm the instruction. See id. at 711 n.4.
III. Conclusion
To the extent that Collier suggests other issues with the Arkansas State Police
and the proceedings in the district court,8 we consider the issues inadequately briefed
and his arguments waived. The judgment of the district court is affirmed.
______________________________
8See, e.g., Appellant’s Br. at i (referring to “numerous contested issues” at the
district court); id. at 9 (claiming that the Arkansas State Police’s dog-training
program is “defunct”); id. at 10 (claiming that “a chasm of errors and discrepancies
exist[s]” in the Arkansas State Police’s official records).

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