Peo v. Brown

22CA1850 Peo v Brown 11-26-2025

COLORADO COURT OF APPEALS

Court of Appeals No. 22CA1850
Adams County District Court No. 20CR2376
Honorable Caryn A. Datz, Judge

The People of the State of Colorado,

Plaintiff-Appellee,

v.

Sareya Nique Brown,

Defendant-Appellant.

JUDGMENT AFFIRMED

Division II
Opinion by JUDGE BROWN
Fox and Meirink, JJ., concur

NOT PUBLISHED PURSUANT TO C.A.R. 35(e)
Announced November 26, 2025

Philip J. Weiser, Attorney General, Carmen Moraleda, Senior Assistant
Attorney General, Denver, Colorado, for Plaintiff-Appellee

Megan A. Ring, Colorado State Public Defender, Dilyn K. Myers, Deputy State
Public Defender, Denver, Colorado, for Defendant-Appellant
¶1 Defendant, Sareya Nique Brown, appeals the judgment of

conviction entered on a jury verdict finding her guilty of several

offenses arising from a car accident, including criminally negligent

homicide, reckless driving, and careless driving. Brown contends

that the district court made multiple evidentiary errors and that the

cumulative effect of those errors requires reversal. We affirm.

I. Background

¶2 In June 2020, Brown found out that the victim was having an

affair with her husband, so she drove her black Suburban to the

victim’s neighborhood. Brown saw the victim come out of her house

and get into a gold sedan. Through her open passenger side

window, Brown asked the victim if they could talk. The victim did

not respond and instead drove away. Brown followed the victim.

¶3 Still in the victim’s neighborhood, Brown pulled into the left

lane on a two-lane road, driving against the direction of traffic and

beside the victim’s car, and “loudly” asked the victim to pull over to

talk. Again, the victim did not react. Brown later admitted that she

understood at that time that the victim did not want to talk.

¶4 Although Brown testified that she and the victim were both

driving normally and that they came to a complete stop before

1
turning out of the victim’s neighborhood onto Peoria Street, a

witness testified that the cars sped past him, that it looked like the

black Suburban was chasing the gold sedan, and that the

Suburban cut off the sedan at a light at Peoria Street. While she

was driving, the victim called 911 and told dispatch that Brown was

chasing her because Brown thought she was having an affair with

Brown’s husband.

¶5 Brown testified that as the cars approached a bridge on Peoria

Street, Brown was driving in the left lane, and the victim was

driving in the center lane. On the bridge, the victim tried to merge

in front of Brown to avoid a car ahead of her in the center lane, but

the victim clipped the front of Brown’s car. The victim’s car crossed

into and collided with oncoming traffic; the victim died instantly.

Brown continued driving and left the scene.

¶6 The prosecution charged Brown with vehicular homicide

(reckless driving) and leaving the scene of an accident involving

death. The district court held a four-day jury trial. The jury

acquitted Brown of vehicular homicide but found her guilty of the

lesser nonincluded offenses of criminally negligent homicide,

reckless driving, and careless driving, and of leaving the scene of an

2
accident involving death. The court sentenced Brown to a

controlling term of seven years in the custody of the Department of

Corrections for leaving the scene and ordered the sentences on the

other counts to be served concurrently.

II. Evidentiary Challenges

¶7 Brown contends that the district court erred by (1) precluding

her from introducing evidence that the victim had marijuana in her

system when she died; (2) allowing an expert to speculate and

usurp the role of the jury; and (3) admitting irrelevant and

prejudicial text messages. We address and reject each contention.

A. Standard of Review

¶8 We review a trial court’s evidentiary rulings for an abuse of

discretion. Zapata v. People, 2018 CO 82, ¶ 25. A court abuses its

discretion when its ruling is manifestly arbitrary, unreasonable, or

unfair, or if it misconstrues or misapplies the law. People v. Liggett,

2021 COA 51, ¶ 16, aff’d, 2023 CO 22.

¶9 We review preserved evidentiary claims for harmless error.

Hagos v. People, 2012 CO 63, ¶ 12. We reverse under this standard

only “if the error ‘substantially influenced the verdict or affected the

3
fairness of the trial proceedings.’” Id. (quoting Tevlin v. People, 715

P.2d 338, 342 (Colo. 1986)).

¶ 10 We review unpreserved evidentiary claims for plain error. Id.

at ¶ 14. Plain error is error that is obvious and substantial, such

that it so undermines the fundamental fairness of the trial as to

cast serious doubt on the reliability of the judgment of conviction.

Id. For an error to be “plain,” it “must be so clear-cut, so obvious,

that a trial judge should be able to avoid it without benefit of

objection.” People v. Pollard, 2013 COA 31M, ¶ 39. Generally, for

an error to be obvious, it must contravene a statute or rule, a

well-settled legal principle, or established Colorado case law.

Campbell v. People, 2020 CO 49, ¶ 25.

B. Evidence of Marijuana in the Victim’s System

¶ 11 Brown contends that the district court erred by precluding

evidence that the victim had marijuana in her system at the time of

the accident because it was relevant to whether Brown caused the

victim’s death.1 We are not persuaded.

1 Because the jury acquitted Brown of vehicular homicide and her

convictions for reckless and careless driving do not require that she
caused the victim’s death, we analyze Brown’s argument only as it
relates to her conviction for criminally negligent homicide.

4
1. Additional Background

¶ 12 On the first morning of trial, the prosecutor moved to preclude

evidence of the victim’s failure to use a seatbelt, arguing that it was

not relevant because it was not an intervening cause. Although

defense counsel responded that he was not raising an intervening

cause defense, he argued that the totality of the facts were relevant

to determine causation, including the fact that the victim “had

about twice the legal limit of marijuana in her system at the time of

the accident,” “was on the phone,” “was not wearing a seat belt[,]

and . . . [swerved] into Ms. Brown by changing lanes without using

a turn signal.” Defense counsel argued that these facts collectively

demonstrated the victim’s unforeseeable gross negligence.

¶ 13 In excluding the evidence, the court ruled,

[W]hether or not [the victim] may have had
marijuana in her system or was not using a
seat belt are factors that would be foreseeable,
and they do not amount to gross negligence
that would substantiate an intervening cause
that would break the chain of causation from
the actions that are alleged to have occurred
which are that Ms. Brown was traveling behind
[the victim] allegedly in a reckless manner but
ultimately resulted in a collision and
ultimately the death of [the victim].

5
The court also reasoned that evidence of the victim’s marijuana use

or failure to wear a seatbelt would only confuse or mislead the jury

on the issue of proximate cause.

2. The District Court Did Not Abuse Its Discretion by Excluding
Evidence That the Victim Had Marijuana in Her System

¶ 14 Brown contends that the district court erred by excluding

evidence that the victim had marijuana in her system.2 She argues

that the victim’s marijuana use was relevant because it made it

more probable that the victim’s own conduct was the sole cause of

the accident. She asserts that the victim’s marijuana use did not

have to be an intervening cause for the evidence to be admissible.

Alternatively, she asserts that the victim’s marijuana use

constituted an intervening cause because it amounted to

unforeseeable gross negligence. Brown also contends that the court

2 On appeal, the People contend that there was no evidence that the

victim drove intoxicated, but a document attached to the
presentence investigation report reflects that the victim’s blood
contained “10 ng/mL” of “Delta-9 THC,” which is sufficient to
presume the victim was driving under the influence. See § 42-4-
1301(6)(a)(IV), C.R.S. 2025 (it can be presumed that a driver is
under the influence of drugs if their blood contains five or more
nanograms of delta-9 THC).

6
infringed on her constitutional right to present a complete defense

by excluding the evidence. We are not persuaded.

¶ 15 Except where “otherwise provided by constitution, statute, or

rule, all relevant evidence is admissible.” People v. Rath, 44 P.3d

1033, 1038 (Colo. 2002) (citing CRE 402). Evidence is relevant if it

has “any tendency to make the existence of any fact that is of

consequence to the determination of the action more probable or

less probable than it would be without the evidence.” CRE 401.

But under CRE 403, even relevant evidence “may be excluded if its

probative value is substantially outweighed by the danger of unfair

prejudice, confusion of the issues, or misleading the jury.”

¶ 16 A person commits criminally negligent homicide when they

“cause[] the death of another person by conduct amounting to

criminal negligence.” § 18-3-105, C.R.S. 2025. “A person acts with

criminal negligence when, through a gross deviation from the

standard of care that a reasonable person would exercise, [the

person] fails to perceive a substantial and unjustifiable risk that a

result will occur or that a circumstance exists.” § 18-1-501(3),

C.R.S. 2025.

7
¶ 17 “A defendant’s conduct is a cause of a victim’s death in a

criminal homicide if the conduct ‘began a chain of events the

natural and probable consequence of which was the victim’s

death.’” People v. Reynolds, 252 P.3d 1128, 1131 (Colo. App. 2010)

(quoting People v. Lopez, 97 P.3d 277, 280 (Colo. App. 2004)). In

this way, the defendant’s conduct must not only be a cause of the

victim’s death, but it must also be a proximate cause of the victim’s

death. Lopez, 97 P.3d at 280 (“Proximate cause . . . means a cause

which in natural and probable sequence produced the claimed

injury. It is a cause without which the claimed injury would not

have been sustained.” (quoting People v. Stewart, 55 P.3d 107, 116

(Colo. 2002))). There can be more than one proximate cause of a

victim’s death, and a “defendant’s conduct does not have to be the

only, nearest, or last cause of death, so long as it is a cause but for

which the death would not have occurred.” Id.

¶ 18 A defendant cannot be held criminally responsible for causing

a victim’s death, however, “if the ‘act of an independent person . . .

destroys the causal connection between the defendant’s act and the

victim’s injury.’” Reynolds, 252 P.3d at 1131 (quoting People v.

Saavedra-Rodriguez, 971 P.2d 223, 225-26 (Colo. 1998)). To qualify

8
as an intervening cause that relieves a defendant of criminal

liability, “an event must exhibit three qualities: (1) the defendant

must not have participated in the event[;] (2) the event must not

have been reasonably foreseeable[;] and (3) the event must have

been a cause but for which the injury would not have occurred.”

People v. Beverly, 2025 CO 18, ¶ 25. An intervening cause

interrupts the natural and probable sequence of events from the

defendant’s conduct; it destroys the causal connection between the

defendant’s conduct and the victim’s injury and becomes the cause

of the victim’s injury. Lopez, 97 P.3d at 282.

¶ 19 To assert that a victim’s contributory negligence caused their

own death, the defendant must show that the victim’s conduct

amounted to an intervening cause. See id. at 281 (“A victim’s

contributory negligence is not a defense to a vehicular homicide

charge unless the negligence was an intervening cause.” (citing

People v. Dunhill, 570 P.2d 1097, 1098 (Colo. App. 1977))). Simple

negligence is foreseeable and does not constitute an intervening

cause. Stewart, 55 P.3d at 121. But gross negligence is

unforeseeable and can be an intervening cause. Id. “Gross

negligence is abnormal human behavior that constitutes ‘an

9
extreme departure from the ordinary standard of care.’” People v.

Smoots, 2013 COA 152, ¶ 10 (quoting Lopez, 97 P.3d at 282), aff’d

sub nom., Reyna-Abarca v. People, 2017 CO 15; see Martinez v.

People, 2024 CO 6M, ¶ 14 (“Gross negligence is willful and wanton

conduct, that is, action committed recklessly, with conscious

disregard for the safety of others.” (citation omitted)).

¶ 20 Here, it was undisputed that the victim’s own driving conduct

was the nearest or last cause of the accident that killed her. The

district court admitted evidence that the victim was speeding,

talking on the phone, and changed lanes too closely to Brown’s car,

clipping the front of Brown’s car and sending the victim’s car into

oncoming traffic. But the prosecution’s theory at trial was that, but

for Brown following the victim, the victim would not have driven the

way she did. It was undisputed that Brown followed the victim in

her car until the victim crashed, even if it was hotly disputed that

Brown could be held criminally liable for doing so. Thus, whether

the victim had marijuana in her system (or drove intoxicated) was

only relevant to causation if it was an intervening cause because

only an act that broke the chain of events that began when Brown

10
followed the victim would make it less probable that Brown was

criminally liable for the victim’s death. See Lopez, 97 P.3d at 282.

¶ 21 To begin with, the victim’s use of marijuana was not an

“intervening” act because it occurred before Brown’s unlawful

conduct. See Auman v. People, 109 P.3d 647, 663 (Colo. 2005)

(third party’s methamphetamine use occurred before the

defendant’s unlawful conduct so it could not constitute an

intervening cause); Stewart, 55 P.3d at 121 (third party’s grossly

negligent act occurred before the defendant’s unlawful conduct so

the act “would not constitute a ‘break’ in the causal chain launched

by [the defendant]’s misconduct” and therefore could not be an

intervening cause).

¶ 22 There was also no evidence that the victim’s marijuana use

was an event “but for which the injury would not have occurred.”

Beverly, ¶ 25. The victim’s death did not result from marijuana

use. And there was no evidence that the victim would have avoided

the accident if she did not have marijuana in her system. See

Saavedra-Rodriguez, 971 P.2d at 227 (“[I]n order to discharge a

defendant of liability for homicide, an intervening act must be” an

act “but for which the victim would not have died.”); see also Lopez,

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97 P.3d at 281 (The victim’s failure to use a seatbelt “had nothing to

do with [the] defendant’s driving conduct,” “was not a contributing

factor in the collision of the two vehicles,” and “would not have

caused [the victim’s] death in the absence of [the] defendant’s

reckless driving.”). In other words, there was no evidence that the

victim drove the way she did because she used marijuana.

¶ 23 To the extent Brown argues that the intervening event was not

the victim’s use of marijuana but her choice to drive after using

marijuana, we conclude that the event still does not constitute an

intervening cause. Brown participated in the event by chasing after

the victim in her car. See Reynolds, 252 P.3d at 1131 (“[W]hen a

later event contributes to the outcome, but would not have occurred

but for the defendant’s own conduct, the later event is not

independent of the defendant’s conduct and does not operate to

relieve the defendant of liability.”). And absent evidence that the

victim’s marijuana use actually impacted her driving, we cannot say

that the court erred by determining that the victim engaged in

foreseeable simple negligence, not gross negligence, by driving with

marijuana in her system. See Martinez, ¶ 39 (“Acts aren’t

inherently unforeseeable because they exceed the law’s limits.”).

12
¶ 24 We conclude that the district court did not abuse its discretion

when it determined that evidence that the victim had consumed

marijuana was not relevant because it was not an intervening

cause. See Zapata, ¶ 25; Liggett, ¶ 16. Relatedly, we perceive no

error in the court’s reasoning that admitting the evidence would

have confused the jury because it could not have, as a legal matter,

relieved Brown of liability. Thus, we also conclude that the court

did not abuse its discretion by excluding the evidence under CRE

403. See Zapata, ¶ 25; Liggett, ¶ 16. And because we conclude

that the court did not err by excluding the evidence, we conclude

that the court did not violate Brown’s constitutional right to present

a defense. See People v. Elmarr, 2015 CO 53, ¶ 27 (“[T]he right to

present a defense is generally subject to, and constrained by,

familiar and well-established limits on the admissibility of

evidence.”); People v. Salazar, 2012 CO 20, ¶ 17 (the constitutional

right to present a defense “requires only that the accused be

permitted to introduce all relevant and admissible evidence”).

C. Expert Testimony

¶ 25 Brown contends that the district court erred by allowing an

expert to (1) speculate as to the victim’s state of mind and (2) usurp

13
the role of the jury by opining on causation. We perceive no

reversible error.

1. Additional Background

¶ 26 At trial, Officer Justin Thull testified as an expert in accident

investigation and accident reconstruction without objection.

During direct examination, the prosecutor asked Officer Thull

“What necessitated [the victim’s] lane change?” Defense counsel

objected based on speculation and the district court said,

“Overruled. [The prosecutor] can lay further foundation.”

¶ 27 The prosecutor then asked if Officer Thull had reviewed the

other officers’ reports, watched the HALO camera footage, and

reviewed the crime scene photographs to reconstruct the accident.

The officer responded that he had and that it was all relevant for

accident reconstruction because

[y]ou can’t just solely look at the precise
moment that those cars came together. You
have to kind of work backwards and figure out
why those two cars were where they were or
why they were performing the movements or
actions that they were at that time.

[The victim] was moving to the left because she
was traveling — from the HALO camera —
faster than this uninvolved vehicle that was in
front of her. So it looked like to me that she

14
was going to pass that uninvolved vehicle. She
moved over at the time because she needed to
pass.

But Ms. Brown was in that location, and the
contact was created, in essence, because Ms.
Brown was following her around trying to get
her attention or stop her movement or general
nuisance of her getting from point A to point B.

And Ms. Brown put herself in that position for
the contact to occur by her driving behavior
prior to the contact occurring.

Defense counsel did not object.

¶ 28 On redirect examination, the prosecutor asked Officer Thull,

“[B]ased on your review of the investigation, what was going on

when [the victim] had to make the decision about whether to move

right, whether to move left, whether to apply the brakes?” The

officer responded,

[The victim] had been . . . followed, honked at,
blocked, cut off. She was on the phone; so she
was distracted by trying to answer questions,
trying to see where she was going, looking at
where Ms. Brown was.

There’s a whole bunch of things that could
have been involved in her decision making to
make that left as opposed to making a right.

I can’t say completely, but those are some
events that could have been occurring and
going through her mind when she made the
decision to move to the left to pass that car.

15
Defense counsel did not object.

¶ 29 Officer Thull also testified, without objection, “[t]hat at any

time during that following, chasing, cutting off, confrontation, Ms.

Brown could have stopped and discontinued that confrontation

and . . . the left lane movement would not have occurred at all

because Ms. Brown would not have been in the vicinity.”

2. Brown Did Not Preserve Her Contentions

¶ 30 We first conclude that Brown’s contentions are not preserved.

Although defense counsel initially objected to the prosecutor’s

question about why the victim changed lanes on the basis that it

was speculative, the district court’s ruling effectively sustained the

objection by requiring the prosecutor to lay additional foundation.

After the court “overruled” the objection, the witness did not answer

the question; instead, the prosecutor asked additional questions to

lay further foundation. Even so, because counsel did not object

again — either to the prosecutor’s questions or to Officer Thull’s

answers — Brown’s challenge to Officer Thull’s direct testimony is

unpreserved. See People v. Douglas, 2012 COA 57, ¶ 61

(concluding an issue was not preserved when no contemporaneous

objection appeared in the record); Martinez v. People, 2015 CO 16,

16
¶ 14 (a timely and specific objection is necessary to allow the “trial

court a meaningful chance to prevent or correct the error”).

¶ 31 Defense counsel also failed to object to the challenged

testimony on redirect examination. The objection to speculation

made during direct examination — almost forty pages of transcript

earlier — was insufficient to alert the court to a potential error. See

Douglas, ¶ 61; Martinez, ¶ 14. And counsel never objected on the

grounds that the officer usurped the role of the jury (or improperly

opined on Brown’s veracity, to the extent that issue is raised on

appeal). See Douglas, ¶ 61. Accordingly, we review Brown’s

contentions for plain error. See Hagos, ¶ 14.

3. The District Court Did Not Plainly Err by Allowing the Expert
Testimony

a. Speculative Testimony

¶ 32 Brown contends that Officer Thull’s redirect testimony had no

analytically sound basis — “instead, Officer Thull merely guessed

about what could have been going through [the victim’s] mind when

she changed lanes and hit Brown.” We perceive no plain error.

¶ 33 CRE 702 allows for the admission of qualified expert testimony

if it will assist the trier of fact to understand the evidence or to

17
determine a fact in issue. The focus of a Rule 702 inquiry is

whether the proffered evidence is both reliable and relevant. People

v. Shreck, 22 P.3d 68, 77 (Colo. 2001).

¶ 34 Expert testimony “that has no analytically sound basis” is

unreliable and inadmissible. People v. Ramirez, 155 P.3d 371, 378

(Colo. 2007). But “[t]estimony is not speculative simply because [it]

is in the form of an opinion or stated with less than certainty, i.e., ‘I

think’ or ‘it is possible.’” Id. As a result, to determine if an expert’s

testimony is unreliable, “it is not enough for a [district] court to

conclude that the testimony is ‘speculative’”; instead, the court

must determine “whether the scientific principles underlying the

testimony are reasonably reliable, and whether the expert is

qualified to opine on such matters.” Id. at 379.

¶ 35 At the time of the trial, Officer Thull had been a police officer

for twenty-one years and had worked in the traffic division as a

training coordinator teaching accident investigation, training the

police department on new accident reporting systems, and helping

other officers with accident reconstructions. He completed three

levels of an accident reconstruction course that covered what to

look for in an initial investigation, how to determine the speeds of

18
two cars when they collide, and how to reconstruct an accident. He

had also taken another sixteen-hour class about how to gather data

from a vehicle and a forty-hour class on how to analyze and

interpret the data and apply it to an accident.

¶ 36 During direct examination, Officer Thull identified the

evidence he had reviewed and explained that he had to work

backwards to “figure out why those two cars were where they were

or why they were performing the movements or actions that they

were at the time.” Officer Thull then explained what he observed

about the maneuvers of the victim’s vehicle in the moments leading

up to the crash.

¶ 37 During cross-examination, defense counsel asked Officer Thull

whether the victim “could have simply braked and slowed behind”

the car in front of her “like anyone else in traffic” but “chose not to”

slow down and instead “chose to change lanes.” The officer

responded affirmatively. Counsel also asked whether the victim

could have moved into the right lane instead of the left lane, noting

19
that “the accident would not have occurred” if she had done that.

Again, the officer agreed.3

¶ 38 On redirect, the prosecutor directed Officer Thull’s attention to

the questions defense counsel had asked about other maneuvers

the victim could have made besides trying to change lanes in front

of Brown. The officer relied on his accident reconstruction

experience and drew inferences from the evidence to reach a

conclusion as to why the victim changed lanes the way she did. See

id. at 378-79 (expert testimony that shows “the method employed

by the expert in reaching the conclusion is scientifically sound,”

whereas “expert testimony that is connected to existing data only by

a bare assertion resting on the authority of the expert” may be

rejected). He opined that the victim was distracted by talking to

police and worrying about Brown, who had “followed, honked at,

blocked, [and] cut off” the victim. Notably, Officer Thull did not give

3 To the extent Brown contends that the district court erroneously

prevented defense counsel from cross-examining Officer Thull on
whether the victim could have complied with her “legal duty” to
check for Brown’s car before changing lanes even if she was
distracted by Brown’s driving, we perceive no error. It would have
been improper for the officer to opine on the applicable law or the
victim’s compliance with it. See People v. Baker, 2021 CO 29, ¶ 32.

20
a single, definitive opinion as to why the victim changed lanes.

Instead, he listed several factors that could have contributed to the

victim’s decision.4

¶ 39 Defense counsel did not challenge Officer Thull’s accident

reconstruction expertise or the method by which he reached his

opinions. During cross-examination, defense counsel highlighted

other choices the victim could have made to avoid clipping Brown’s

vehicle. And on redirect, Officer Thull drew on his expertise to

identify facts in evidence that could have contributed to the victim’s

decision. Under these circumstances, we conclude that the officer’s

opinion was not speculative. At a minimum, it would not have been

obvious that his testimony lacked a sound scientific basis, so the

district court did not plainly err by admitting it. See id.; Pollard,

¶ 39; Campbell, ¶ 25.

4 We decline to address Brown’s argument, raised for the first time

in her reply brief, that the district court deprived defense counsel of
the opportunity to challenge Officer Thull’s redirect testimony. See
People v. Simpson, 93 P.3d 551, 555 (Colo. App. 2003) (declining to
consider an argument presented for the first time in a reply brief).

21
b. Usurping the Role of the Jury

¶ 40 Brown next contends that the district court erred by allowing

Officer Thull to testify that Brown’s behavior caused the accident

resulting in the victim’s death because that testimony usurped the

role of the jury in determining causation. Again, we perceive no

plain error.

¶ 41 Experts may offer testimony that embraces the ultimate issue

to be decided by the jury, but they may not usurp the role of the

jury. People v. Rector, 248 P.3d 1196, 1203 (Colo. 2011). To

determine whether expert testimony usurped the jury’s role, we

consider several nonexhaustive factors, including whether

(1) the testimony was clarified on
cross-examination; (2) the expert’s testimony
expressed an opinion of the applicable law or
legal standards and thereby usurped the
function of the court; (3) the jury was properly
instructed on the law and that it could accept
or reject the expert’s opinion; and (4) the
expert opined that the defendant had
committed the crime or that there was a
particular likelihood that the defendant did so.

People v. Baker, 2021 CO 29, ¶ 32 (citing Rector, 248 P.3d at 1203).

¶ 42 Officer Thull testified that, although the fatal crash was

caused by the victim changing lanes and clipping the front of

22
Brown’s vehicle, the contact occurred because of Brown’s “following,

chasing, cutting off, [and] confront[ing]” the victim. This testimony

undoubtedly spoke to an element of criminally negligent

homicide — causation. But we conclude that it did not usurp the

jury’s role because it is undisputed that (1) Officer Thull never

opined that Brown committed any offense; (2) he never opined on

the legal definition of causation; and (3) the jury was properly

instructed that Brown had the presumption of innocence, the

prosecution alone had the burden to prove each element of the

offenses beyond a reasonable doubt, the jurors were the sole judges

of witness credibility and the weight to give the evidence, and the

jurors were not bound by an expert’s testimony. The court also

properly instructed the jury that “cause” meant “an act which in

natural and probable sequence produced the claimed injury” and

“without which the claimed injury would not have happened.”

¶ 43 We are not persuaded otherwise by Brown’s argument that

Officer Thull’s testimony “opined on the truth of the prosecution’s

factual allegations.” Although Officer Thull’s testimony bolstered

the prosecution’s case, that did not make it inadmissible. Indeed, if

the evidence did not make it more or less probable that the events

23
occurred as the prosecution alleged, the testimony would not have

been relevant. See CRE 401. And the mere fact that Brown

testified to a different version of events than what Officer Thull

perceived or was told during his investigation does not mean that

he improperly opined on her credibility. See People v. Relaford,

2016 COA 99, ¶ 30 (“[E]xpert testimony generally tends to bolster or

attack the credibility of another witness,” but that “alone is

insufficient to deny admission of the evidence.” (quoting People v.

Koon, 724 P.2d 1367, 1370 (Colo. App. 1986))).

¶ 44 At a minimum, we conclude that it would not have been

obvious to the district court that the officer usurped the role of the

jury, so the court did not plainly err by allowing his testimony. See

Pollard, ¶ 39; Campbell, ¶ 25.

D. Text Messages

¶ 45 Brown contends that the district court abused its discretion by

admitting text messages that contained inadmissible character

evidence, were irrelevant under CRE 401, and were unfairly

prejudicial under CRE 403. We disagree.

24
1. Applicable Law

¶ 46 CRE 404(b) provides that evidence of “any other crime, wrong,

or act is not admissible to prove a person’s character in order to

show that on a particular occasion the person acted in conformity

with the character” but may be admissible “for another purpose,

such as proving motive, opportunity, intent, preparation, plan,

knowledge, identity, absence of mistake, or lack of accident.”

¶ 47 To determine whether evidence of uncharged misconduct is

admissible, we must first determine whether it is intrinsic or

extrinsic to the charged offenses. Rojas v. People, 2022 CO 8, ¶ 52.

“Intrinsic acts are those (1) that directly prove the charged offense

or (2) that occurred contemporaneously with the charged offense

and facilitated the commission of it.” Id. Because intrinsic acts are

not “other” crimes, wrongs, or acts, a trial court need not conduct a

CRE 404(b) analysis when deciding whether to admit the evidence.

Id. Instead, the court should evaluate the admissibility of intrinsic

evidence under CRE 401-403 and other ordinary evidentiary

principles. Id.

¶ 48 In contrast, extrinsic evidence that suggests bad character

may be admitted only as provided by CRE 404(b) and after a Spoto

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analysis. Id.; People v. Spoto, 795 P.2d 1314, 1318-19 (Colo. 1990).

But if extrinsic evidence does not suggest bad character, CRE

404(b) does not apply. Instead, its admissibility is governed by CRE

401-403 and ordinary evidentiary principles, just like intrinsic

evidence. Id.

2. Additional Background

¶ 49 At trial, the prosecutor moved to admit text messages between

the victim and T.B., Brown’s sister-in-law and the victim’s friend.

The texts contained the following messages from T.B. to the victim:

• “The shit is out, and it’s going to be bad.”

• “You better be real careful.”

• “I don’t think you understand the seriousness of this.”

• “This child is mad as fuck, she knows every time he has

been at your house. She has it time stamped.”

• “She is going to fight for her place.”

¶ 50 Defense counsel objected on the basis that the messages

constituted prejudicial character evidence. The prosecutor argued

that the messages were relevant to show the effect on the victim.

The district court told the prosecutor to lay further foundation.

After additional questioning, the prosecutor again moved to admit

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the text messages, and defense counsel argued the texts were not

relevant and were prejudicial.5

¶ 51 The court ruled, in relevant part, that “[t]he text messages are

relevant in that they are a conversation between [T.B.] and [the

victim] regarding [T.B.’s] knowledge that [Brown] is upset with [the

victim] and is actively looking for her. And this precipitates the date

of offense by one day.” The court explained that, although there

may be “prejudicial components to the substance of the messages,

the [c]ourt does find that they are more probative than prejudicial.”

3. The District Court Did Not Abuse Its Discretion by Admitting
the Text Messages

¶ 52 Brown contends that the district court abused its discretion by

admitting the text messages because the texts (1) contained

inadmissible character evidence and (2) were irrelevant under CRE

401 and inadmissible under CRE 403. We are not persuaded.

5 Brown also argued during trial that the text messages should be

excluded as hearsay, but she does not reassert that argument on
appeal, so we deem it abandoned. See People v. Hunsaker, 2020
COA 48, ¶ 10, aff’d, 2021 CO 83.

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a. Character Evidence

¶ 53 To the extent Brown contends that the district court

erroneously admitted the text messages under the abolished res

gestae doctrine, rather than conducting a proper CRE 404(b)

analysis, we conclude that the argument was not preserved and is

not developed on appeal.6 Although defense counsel filed a motion

in limine to exclude “character evidence” and asserted at trial that

the text messages contained “character evidence,” counsel did not

ask the court to conduct a CRE 404(b) or Spoto analysis, nor did

counsel frame the argument in those terms. See People v.

Melendez, 102 P.3d 315, 322 (Colo. 2004) (a defendant must raise

an issue and provide a trial court with “an adequate opportunity to

make findings of fact and conclusions of law”); see also CRE 404(b).

Thus, the issue is not preserved.

¶ 54 But even if counsel’s assertion that the messages contained

“prejudicial character evidence” preserved the issue, Brown does

6 To argue that the district court admitted the evidence under the

res gestae doctrine, Brown appears to be relying upon the court’s
pretrial ruling that the text messages’ “probative value” was to
“explain and to place into context” the events that occurred. But
Brown never raised an objection on the basis that the court was
improperly relying on the res gestae doctrine.

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not explain on appeal how the text messages were extrinsic other

acts evidence subject to a CRE 404(b) or Spoto analysis, nor does

she conduct that analysis to demonstrate that the court erred.

Thus, we decline to address Brown’s “character evidence”

arguments further. See People v. Rodriguez-Morelos, 2022 COA

107M, ¶ 49 (declining to address a defendant’s conclusory and

underdeveloped argument), aff’d, 2025 CO 2.

b. CRE 401 and CRE 403

¶ 55 Brown argues that the text messages offered “minimal, if any[,]

probative value showing Brown’s motive for approaching [the

victim]” because Brown did not dispute that she wanted to speak

with the victim about the affair when she went to the victim’s

house. But a defendant “‘may not stipulate or admit [her] way out

of the full evidentiary force of the case as the [prosecution] chooses

to present it.’” People v. Morales, 2012 COA 2, ¶ 9 (second

alteration in original) (quoting Old Chief v. United States, 519 U.S.

172, 186-87 (1997)). And Brown never admitted she was angry or

wanted to confront the victim as the text messages showed.

¶ 56 Brown testified that she was driving normally and did not

honk at, tailgate, or threaten the victim, or do anything else to

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make the victim stop. Yet other evidence contradicted that account.

One witness said it looked like Brown’s Suburban was chasing the

victim’s car. And T.B. testified that she was on the phone with

Brown when Brown was following the victim and could hear Brown

“screaming” at the victim to pull over. Given the conflicting

evidence, the text messages made it more probable that Brown

pursued the victim aggressively, as the other witnesses described,

rather than calmly following her and politely asking her to talk, as

Brown testified. See CRE 401; Vialpando v. People, 727 P.2d 1090,

1096 (Colo. 1986) (we consider “whether the fact of consequence for

which the evidence is offered is being disputed”).

¶ 57 The text messages also reflected Brown’s motive. “‘[M]otive is

always relevant’ to establish whether the defendant committed the

charged act and why, and may also explain otherwise unexplainable

behavior.” People v. Delsordo, 2014 COA 174, ¶ 14 (quoting

Wagman v. Knorr, 195 P. 1034, 1035 (Colo. 1921)). The evidence

was also relevant to show Brown’s mental state because the highest

charge of vehicular homicide required the prosecution to prove that

Brown drove her car recklessly. § 18-3-106(1)(a), C.R.S. 2025.

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¶ 58 We also reject Brown’s argument that the text messages were

unfairly prejudicial because of the danger the jury would assume

that Brown went to the victim’s house with “violent intent.”

¶ 59 “All relevant and admissible evidence is ‘inherently

prejudicial’” to at least one of the parties. People v. Kembel, 2023

CO 5, ¶ 53 (citation omitted). And “any evidence that strengthens

the prosecution’s case carries with it some degree of disadvantage

to an accused.” People v. Garner, 806 P.2d 366, 375 (Colo. 1991).

“[U]nfair prejudice within the meaning of the rule still refers only to

‘an undue tendency on the part of admissible evidence to suggest a

decision made on an improper basis’ and does not mean prejudice

that results from the legitimate probative force of the evidence.”

Rath, 44 P.3d at 1043 (citation omitted). And when we review a

trial court’s ruling under CRE 403, “we assume the maximum

probative value that a reasonable fact finder might give the evidence

and the minimum unfair prejudice to be reasonably expected.”

People v. Clark, 2015 COA 44, ¶ 18 (citation omitted).

¶ 60 From the legitimate probative force of the text messages, a

reasonable jury could conclude that Brown was upset, had a motive

for going to the victim’s house, and pursued the victim aggressively,

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putting in motion a chain of events culminating in the victim’s

death. Brown has not demonstrated that the prejudice to her from

admitting this evidence was unfair prejudice. See Rath, 44 P.3d at

1043. Affording the evidence its maximum probative value and its

minimum unfair prejudice, see Clark, ¶ 18, we conclude that the

court did not abuse its discretion by admitting the text messages.

III. Cumulative Error

¶ 61 Brown contends that, even if the alleged errors do not

individually require reversal, their cumulative prejudicial impact

does. But because we have found no error, the cumulative error

doctrine does not apply. See Howard-Walker v. People, 2019 CO 69,

¶ 25 (“For reversal to occur based on cumulative error, a reviewing

court must identify multiple errors that collectively prejudice the

substantial rights of the defendant, even if any single error does

not.”); People v. Shanks, 2019 COA 160, ¶ 76 (cumulative error

doctrine only applies when multiple errors were committed).

IV. Disposition

¶ 62 We affirm the judgment.

JUDGE FOX and JUDGE MEIRINK concur.

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