Peo v. Derossett

22CA1585 Peo v Derossett 06-25-2026

COLORADO COURT OF APPEALS

Court of Appeals No. 22CA1585
Jefferson County District Court No. 20CR4
Honorable Diego G. Hunt, Judge

The People of the State of Colorado,

Plaintiff-Appellee,

v.

Stephen Douglas Derossett,

Defendant-Appellant.

JUDGMENT AFFIRMED

Division IV
Opinion by JUDGE FREYRE
Brown and Schutz, JJ., concur

NOT PUBLISHED PURSUANT TO C.A.R. 35(e)
Announced June 25, 2026

Philip J. Weiser, Attorney General, Brenna A. Brackett, Assistant Attorney
General, Denver, Colorado, for Plaintiff-Appellee

Megan A. Ring, Colorado State Public Defender, Meredith K. Rose, Deputy
State Public Defender, Denver, Colorado, for Defendant-Appellant
¶1 Defendant, Stephen Douglas DeRossett,1 appeals the

judgment of conviction entered on a jury verdict finding him guilty

of second degree murder. We affirm the judgment.

I. Background

¶2 DeRossett and the victim, Keli Jackson, began dating in July

2019. In October, DeRossett moved into Jackson’s house.

¶3 On January 1, 2020, at around 11 a.m., DeRossett called 911.

At the beginning of the call, Jackson can be heard saying, “Hurry,

I’m going to die.” Out of breath, DeRossett requested an

ambulance. DeRossett said that Jackson had too much to drink

and that she started “coming at him,” so he pushed her down the

stairs. He then said that Jackson kept trying to hit him and that

she had a knife. When the dispatcher asked DeRossett if Jackson

cut him, he responded that he didn’t know because it happened so

fast and that his face hurt but that he didn’t know if it was

bleeding. When asked for the second time if Jackson cut him,

DeRossett responded, “[Y]es,” but then said that he had blood all

over him but didn’t know what happened. DeRossett then

1 The briefs sometimes style DeRossett as “Derossett.” We follow
the style in the opening brief.

1
mentioned that Jackson was bleeding. Three and a half minutes

into the call, DeRossett told the operator that Jackson was having a

hard time breathing.

¶4 Later in the 911 conversation, DeRossett stated that Jackson

came at him with the knife, he took the knife from her, he told her

to get the hell away from him, and he called 911. A minute later,

DeRossett stated that the two were taking shots, Jackson started

acting weird, and then she began swinging at him. DeRossett said

he did not know what he did, but then Jackson grabbed the knife,

and he ended up covered in blood. When DeRossett said that

Jackson was not moving, the operator asked him if Jackson was

breathing, and DeRossett responded that he didn’t know and that

he didn’t do anything.

¶5 When paramedics arrived, Jackson was lying in a pool of

blood, was unconscious and unresponsive, had no pulse, and was

not breathing. She was declared dead at the scene. Police found a

knife with blood on it on a nearby couch. The knife had DeRossett’s

name engraved on its blade.

¶6 Following an autopsy, the forensic pathologist, Dr. Dawn

Holmes, concluded that Jackson died of blood loss from a total of

2
fifteen stab wounds. The autopsy revealed multiple sharp-force

injuries including both stab wounds (deep, sharp-force injuries) and

incised wounds (more shallow, sharp-force injuries), as well as

abrasions and bruises. Dr. Holmes testified that four of the stab

wounds were lethal, meaning that they were wounds that entered a

vessel or an organ and were capable of causing death.

¶7 While paramedics tried to revive Jackson, DeRossett was

escorted outside to the driveway. DeRossett told a responding

officer that he and Jackson had been drinking and that Jackson

was acting silly. DeRossett then said that Jackson came at him

and that he did not know what happened after that. After

DeRossett complained of chest pain, he was placed in an

ambulance. While in the ambulance, DeRossett repeated that

Jackson was acting silly, that she came at him with a knife, and

that he did not know what happened.

¶8 Following treatment at the hospital, DeRossett was taken to

the police station. There, he told another police officer that he

could not believe the situation he was in, that he was just trying to

help Jackson, and that he was trying to defend himself against her.

He also said that he “was in a daze, and that he just recalled seeing

3
her hair flying about, and then she was sitting down, and that’s

when [he] noticed the blood.” DeRossett had scratches on his face,

on both sides of his nose, on the underside of his chin, and on his

chest, as well as scratches on his lower back, left wrist, right pinky

finger, and right forearm. DeRossett also had “what appeared to be

rug-burn-type injuries” on each knee.

¶9 DeRossett’s blood was drawn at the hospital, and an

extrapolation analysis indicated that his blood alcohol level was

around 0.116 at the time he called 911. The analysis also showed

DeRossett had THC in his blood.

¶ 10 The State charged DeRossett with first degree murder and two

crime of violence sentencer enhancer counts. DeRossett asserted

self-defense. Alternatively, he argued that he lacked the requisite

mental state for first or second degree murder due to a combination

of factors, including his intoxication at the time of the incident and

the lasting effects of a previous brain injury.

¶ 11 The jury acquitted DeRossett of first degree murder but found

him guilty of second degree murder and the two crime of violence

counts. The court sentenced him to forty years in the custody of

the Department of Corrections.

4
¶ 12 On appeal, DeRossett contends that the trial court erred by

(1) admitting thirty-three photographs of Jackson’s dead body;

(2) permitting a psychologist’s opinion that DeRossett had aspects

of three different personality disorders offered to rebut defense

evidence that a prior traumatic brain injury affected DeRossett’s

mental condition at the time of the killing; and (3) denying

DeRossett’s tendered instruction on mental condition evidence

without offering an alternative under section 16-8-107(1)(a), C.R.S.

2025. DeRossett also asserts cumulative error. Although we

identify some errors, we conclude they are harmless and affirm the

judgment.

II. Photographs

¶ 13 DeRossett contends that the trial court reversibly erred by

admitting thirty-three photographs of Jackson’s dead body. We

agree that many of the photographs were unnecessary and

cumulative but conclude that the error in their admission is

harmless and does not require reversal.

5
A. Additional Background

¶ 14 On the fourth day of trial, the prosecution moved to introduce

thirty-three autopsy photographs. DeRossett’s counsel objected to

the group as a whole, arguing,

Every single one of these are autopsy
photos. . . . I understand the prosecution
introduces some exhibits on the autopsy, but I
think this is cumulative, prejudicial, and
whether intended or not . . .

....

[h]as the effect of inflaming the emotions and
passions of the jury because of the . . . graphic
nature of these photos. . . . [I]n going through
these photos quickly, I don’t think they need
all of them.

. . . I do understand that they’re going to have
the pathologist testify. The pathologist can be
referring to some of the photos, but this is just
overwhelming evidence . . . that’s of an
emotional nature.

So based on Mr. DeRossett’s state and
constitutional rights to a fair trial, right to
effective assistance of counsel, right to a fair
jury, I’m objecting to all of these photos being
admitted.

If . . . there’s a culling of the photos, I
understand, . . . some are going to be
admitted, but this massive number of photos
and given the graphic nature of these photos, I
am objecting based on the legal principles I’ve
cited.

6
¶ 15 When the trial court asked DeRossett to identify the specific

photos he believed were cumulative, DeRossett listed the following

exhibit numbers: 114-117, 119, 122, 124, 126, 127, 129-132, 142,

and 144. The prosecution responded:

We already have culled down the photographs
that the People anticipated admitting from the
multitude of photographs that were taken at
the autopsy.

The People don’t intend to publish any of these
through [the crime scene analyst], but through
Dr. Holmes, and she would be testifying
specifically to each one with regard to the . . .
injuries that are seen.

As described in the exhibit list, these are not
cumulative, as the Court has even stated.
There could be close-ups, different angles.
That does not render them cumulative. So the
People would . . . request that the objection is
denied.

This is relevant evidence pursuant to [CRE]
401. . . . [I]t may be excluded if its probative
value is substantially outweighed by the
danger of unfair prejudice; we do not have that
here.

¶ 16 After confirming with the prosecution that Dr. Holmes would

be referencing each of the exhibits individually in her testimony, the

trial court overruled DeRossett’s objection.

7
¶ 17 During Dr. Holmes’ testimony, she explained Jackson’s

various stab wounds, abrasions, and bruises as the prosecution

showed the autopsy photographs. At one point, when identifying a

lethal stab wound, Dr. Holmes commented that the wound could be

seen better in a different photograph.

¶ 18 After the introduction of nine of the photographs, DeRossett

renewed his objection.

I want to renew my objection with respect to
these photographs, the cumulative nature of
these photographs, and the . . . emotional and
impassioned prejudice that they create.

Even Dr. Holmes when she was testifying was
referring to certain photographs saying,
“Actually the other photograph was a better
version,” and so . . . each individual
photograph is not representing a different
injury for Dr. Holmes’ testimony. In fact, she’s
even said that certain photos are not as helpful
as other photos. So I just want to renew that
objection that I made earlier.

¶ 19 The trial court responded:

All right. And I will note that Mr. DeRossett is
. . . the individual who is reacting emotionally
to — at least visibly to the exhibits, and the
witness was indicating a prior exhibit was
more helpful to illustrate her testimony
concerning a particular injury.

8
However, she did give testimony with respect
to the exhibit that was referenced, and by the
People, that was an earlier exhibit which was
given in the course of her testimony. So I . . .
don’t find it to be cumulative.

¶ 20 Dr. Holmes then resumed her testimony.

B. Standard of Review and Applicable Law

¶ 21 “We review a trial court’s evidentiary rulings for abuse of

discretion.” Nicholls v. People, 2017 CO 71, ¶ 17. “A trial court

abuses its discretion when its ruling is manifestly arbitrary,

unreasonable, or unfair, or when the trial court misapplies or

misconstrues the law.” Fisher v. People, 2020 CO 70, ¶ 13. Under

this standard, “we ask not whether we would have reached a

different result but, rather, whether the trial court’s decision fell

within the range of reasonable options.” People v. Archer, 2022

COA 71, ¶ 23 (quoting Hall v. Moreno, 2012 CO 14, ¶ 54). We

review a preserved evidentiary error under the nonconstitutional

harmless error standard. Hagos v. People, 2012 CO 63, ¶ 12

(requiring reversal only if the error substantially influenced the

verdict or affected the fairness of the trial proceedings).

¶ 22 In general, all relevant evidence is admissible. CRE 402.

Evidence is relevant if it tends to make the existence of any fact of

9
consequence to the determination of the action more probable or

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

¶ 23 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. CRE 403. Evidence

is considered unfairly prejudicial if it has an “undue tendency to

suggest a decision on an improper basis . . . such as sympathy,

hatred, contempt, retribution, or horror.” People v. Clark, 2015

COA 44, ¶ 18 (citation omitted). In reviewing a trial court’s

determination 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.” Clark, ¶ 18

(citation omitted).

¶ 24 In general, photographs “may be used to graphically portray,

among other things, the scene of a crime, the identification of a

victim, the appearance and condition of the deceased, and the

location, nature and extent of the wounds or injuries, all of which

matters are relevant.” Young v. People, 488 P.2d 567, 574 (Colo.

1971). “Photographs of victims illustrating the appearance of the

victim’s body at the scene of the crime or the nature and location of

10
the victim’s injuries are generally relevant because they tend to

show whether and how the offenses were committed.” People v.

Herrera, 2012 COA 13, ¶ 34; see also People v. Mattas, 645 P.2d

254, 260 (Colo. 1982) (“It is within the trial court’s discretion to

decide whether photographs are unnecessarily gruesome or

inflammatory, and the court’s decision will be reversed only upon

abuse of that discretion.”). The trial court must “exercise its

discretion and weigh the probative value of this evidence against its

inflammatory effect” when determining whether to admit such

photos. People v. Zekany, 833 P.2d 774, 777 (Colo. App. 1991).

¶ 25 Colorado courts approve of the admission of graphic photos

only when it assists in proving a material fact. See People v.

Carrier, 791 P.2d 1204, 1205 (Colo. App. 1990). But when graphic

photos lack probative value, their admission constitutes reversible

error. Archina v. People, 307 P.2d 1083, 1095 (Colo. 1957)

(concluding that pictures of a naked body on a marble slab had no

probative value).

¶ 26 A person commits the crime of first degree murder if, “[a]fter

deliberation and with the intent to cause the death of a person

other than himself, he causes the death of that person.”

11
§ 18-3-102(1)(a), C.R.S. 2025. A person commits the crime of

second degree murder if, “the person knowingly causes the death of

a person.” § 18-3-103(1)(a), C.R.S. 2025.

¶ 27 Under section 18-1-704(1), C.R.S. 2025, a person has the right

to use force to defend himself from the use or imminent use of

unlawful physical force by another person, and he may use a degree

of force that he reasonably believes is necessary for that purpose.

See People v. Luna, 2020 COA 123M, ¶ 26 (“Although the

affirmative defense of self-defense takes into account the actual

belief or state of mind of a defendant, it ultimately requires that a

reasonable person would have believed and acted as the defendant

did.”).

¶ 28 When self-defense is asserted as an affirmative defense, the

defendant generally admits the commission of the elements of the

charged act but seeks to justify the act. People v. Pickering, 276

P.3d 553, 555 (Colo. 2011). Disproving the existence of self-defense

becomes an additional element of the offense that the prosecution

must disprove beyond a reasonable doubt. § 18-1-407(2), C.R.S.

2025; see Pickering, 276 P.3d at 556.

12
C. Analysis

¶ 29 We agree with DeRossett that the court abused its discretion

in admitting at least some of the voluminous and often cumulative

autopsy photographs. Indeed, we discern no reason for the many

cumulative photographs of the victim’s body at the morgue or the

cumulative photographs of the victim’s cleaned body.

¶ 30 However, we conclude reversal is not required because the

photographs were highly probative of DeRossett’s specific mental

state — the primary issue the jury had to decide — and whether he

acted in self-defense — particularly, whether stabbing the victim

fifteen times constituted a reasonable response to the threat he

faced. The photographs depicted the location, nature, and extent of

each of the fifteen stab wounds individually as well as collectively

with Jackson’s other injuries. The court instructed the jury on first

and second degree murder and self-defense. The jury had to decide

whether DeRossett acted after deliberation and with intent or

knowingly when he caused Jackson’s death and whether the People

had disproved his assertion of self-defense (i.e., whether DeRossett’s

conduct was a reasonable response to the threat he faced).

13
¶ 31 Additionally, we agree with the People that most of the

photographs offered the jury some different information. Some

photographs are closer up, taken from different angles, and some

include a measuring tool. Moreover, the photographs of Jackson

taken before her body had been cleaned, while cumulative, were not

“gratuitous,” as DeRossett argues, but instead show Jackson’s

wounds in a state more closely resembling how they appeared at

the crime scene. And each of these photographs was discussed by

Dr. Holmes during her testimony. In contrast, the photographs of

Jackson’s cleaned body depict the wounds in a way that was not

visible prior to the cleaning and formed the basis for Dr. Holmes’

opinion. See People v. Marquiz, 685 P.2d 242, 248 (Colo. App.

1984), aff’d, 726 P.2d 1105 (Colo. 1986).

¶ 32 DeRossett’s reliance on Archina v. People, 307 P.2d 1083 (Colo.

1957), is misplaced. In Archina, the primary issue at trial was the

identity of the murderer. The Colorado Supreme Court held that it

was reversible error to admit morgue photographs of the victim’s

naked body taken seventeen days after the shooting that showed

the results of extensive surgery performed after the shooting. In

this case, identity was not an issue; instead, DeRossett’s mental

14
state and his claim of self-defense were the focus. And the autopsy

photographs, which were taken shortly after Jackson’s death,

related directly to those disputed issues. Therefore, Archina is

distinguishable.

¶ 33 Additionally, we reject DeRossett’s argument that the

probative value of the photographs was low because he never

disputed the cause of Jackson’s death. Photographs of a victim

may still have probative value even if they relate to an undisputed

matter. People v. White, 606 P.2d 847, 849 (Colo. 1980)

(“Photographs are not inadmissible solely because the defendant

has stipulated to these matters, or because these matters have been

established through the testimony of prosecution witnesses.”); see

also Jorgenson v. People, 482 P.2d 962, 965 (Colo. 1971)

(photographs of victim at the scene and in the morgue depicting

victim’s injuries properly admitted even when defendant “admit[ted]

to the killing, relying solely on self-defense”). But here, DeRossett’s

mental state and whether he acted in self-defense in stabbing the

victim fifteen times were highly disputed, and the photographs were

probative of those issues. Moreover, “[t]he prosecution is generally

entitled to prove the elements of its case against a defendant by

15
evidence of its own choice, and a defendant ‘may not stipulate or

admit his way out of the full evidentiary force of the case as the

[prosecution] chooses to present it.’” People v. Morales, 2012 COA

2, ¶ 9 (quoting Old Chief v. United States, 519 U.S. 172, 186-87

(1997)).

¶ 34 In the end, while we agree that the court abused its discretion

by admitting an excessive number of autopsy photographs, we

conclude that reversal of DeRossett’s conviction is not required,

because the evidence of his guilt was overwhelming. To begin,

DeRossett admitted that he killed the victim. The only questions for

the jury to decide were whether he did so in self-defense and what

his state of mind was at the time.

¶ 35 Additionally, the evidence showed that DeRossett stabbed the

victim fifteen times. Moreover, DeRossett provided inconsistent

statements of how the victim sustained those wounds. Finally, the

jury’s conviction on the lesser included offense shows that it was

not swayed by the prejudicial photographs and that it carefully

considered the evidence in reaching its decision. See Washington v.

People, 2024 CO 26, ¶ 35 (jury’s verdict on lesser degree of murder

indicated that error did not cause jury to blindly convict defendant).

16
III. Expert Testimony

¶ 36 DeRossett next contends that a psychologist’s opinion that he

diagnosed DeRossett with an unspecified personality disorder —

offered to rebut defense evidence that a serious brain injury affected

DeRossett’s mental condition at the time of the killing — did not

qualify for the exception to the prosecution’s bar under section

16-8-107(1)(a) and was irrelevant and unduly prejudicial. We

disagree.

A. Additional Background

¶ 37 DeRossett initially pleaded not guilty by reason of insanity

(NGRI) under section 16-8-101.5(1)(b), C.R.S. 2025. DeRossett

underwent a court-ordered sanity evaluation by Dr. Charles

Harrison. Based on his interview with DeRossett and his review of

DeRossett’s medical and jail records, Dr. Harrison concluded that,

at the time of the offense, DeRossett

did not suffer from a mental disease or defect
or from a condition of mind caused by a
mental disease or defect that caused him to be
incapable of distinguishing right from wrong or
prevented him from forming the culpable
mental state that is an essential element of the
crimes charged.

17
¶ 38 Therefore, Dr. Harrison opined, DeRossett “was legally sane at

the time of the alleged offense.”

¶ 39 Subsequently, DeRossett withdrew his NGRI plea and gave

notice of his intent to introduce expert witness opinions about his

mental condition under section 16-8-107(3)(b).

¶ 40 In his opening statement, defense counsel discussed

DeRossett’s previous head injury:

Mr. DeRossett decades ago was in a pretty
awful and horrific . . . motorcycle accident.
Mr. DeRossett suffered an extremely serious
head injury, and still suffers from the effects of
that . . . car accident.

You’ll hear that after that motorcycle accident
in southern California when he was in his
twenties, that he was ejected from . . . the
motorcycle. He was hit and struck by another
car.

He was rushed to the Emergency Room, where
he underwent emergency brain surgery . . .
and then remained in the hospital for weeks
and weeks. He couldn’t talk. He couldn’t
walk. He couldn’t communicate. He had lost
a lot of functioning in his brain.

Now, someone like that, after weeks in the
hospital, can’t live on their own, and so he’s
transitioned to a long-term care facility for
rehabilitation for people with head injuries,
and he spent months and months in that
long-term residential care facility . . . .

18
. . . [W]hile he was there, he learned how to
walk and talk and communicate again. And,
yes, as he sits here today, he can talk, he can
walk. He can communicate.

But there are lasting and lingering effects from
that accident that never went away, that he
never fully healed from. He still has
processing issues. He still has difficulty
communicating with people.

He still has difficulty controlling his own
emotions and reading other people’s emotions
and body language. He still has . . . trouble
putting together linear sentences. Still has
trouble hearing, which is why the . . .
interpreter is here.

You’re going to see that he still has a scar.
You can’t see it right now, it’s on the other side
of his head. It spans the entire length of his
head from . . . his left, front to back, from
where the brain surgeon had performed brain
surgery on him, and removed part of his brain.

While Mr. DeRossett was discharged from that
treatment facility decades ago, he still suffers
lingering effects that came into play the day
that this happened.

One of those is the fact that with his head
injury, his sensitivity to alcohol skyrocketed,
as you might imagine. He could no longer
drink like he used to, and alcohol no longer
affected him like it used to.

So with that in mind, that background in
mind, we get to January 1st of 2020. Mr.
DeRossett was drunk, and he was smoking

19
marijuana. Mr. DeRossett and Ms. Jackson
had been fighting.

They had been living together for a few months
at that point, and Mr. DeRossett was quite
frankly frustrating Ms. Jackson. He was being
naggy and needy and messy, and he was
drunk and he was smoking and he lost his job.

And so Ms. Jackson is at the end of her rope,
and their argument turned into a physical
altercation where she picked up a knife, and
she came at him with it. And Mr. DeRossett
was confused. Mr. DeRossett was slow to
process. There was no time to think, no time
to reason. Mr. DeRossett disarmed Ms.
Jackson, and he defended himself until he felt
safe again.

¶ 41 Twice during the cross-examination of the prosecution’s

witnesses, counsel elicited evidence about DeRossett’s scar from the

motorcycle accident. Counsel also elicited evidence that while in

the hospital following the incident, DeRossett seemed confused and

had trouble uttering complete sentences.

¶ 42 DeRossett objected to the prosecution calling Dr. Harrison in

rebuttal and argued that such testimony violated his rights to due

process, a fair trial, confrontation, the presumption of innocence,

remain silent, a fair and impartial jury, and effective assistance of

counsel. The trial court responded:

20
[C]ertainly there was . . . [,] in opening
statements, summation of evidence with
respect to Mr. DeRossett’s traumatic brain
injury, and the lingering effects of the brain
injury on his ability to assess the situation in
the process — I think the term was used about
processing.

There was evidence elicited on cross-
examination concerning the scar that was also
referenced in opening statements that Mr.
DeRossett has, as a result of brain surgery
following the accident; although there hasn’t
been evidence concerning the brain surgery, it
was referenced in opening statement.

There has been evidence elicited concerning
Mr. DeRossett’s presentation or demeanor at
the scene of the crime, and then later at the
hospital, at least for the first part.

There’s been suggestion, although no evidence,
at least suggestion through questions of
counsel concerning medication [sic] with
Adderall in order to sedate Mr. DeRossett given
that he was agitated and . . . there was . . .
some evidence that his statements were
incoherent, at least in the hospital in the first
part, which ties into the defense’s notice with
respect to impaired mental condition. So there
is evidence in the record at this point with
respect to the issue that was introduced to the
jury as part of the defense’s opening.

The defense is also in possession of Dr.
Harrison’s report. . . . [T]he extent to which
the information would be introduced at trial
has been litigated extensively before now, so
it’s not as if the defense is not aware of the

21
contents of the report and the scope of Dr.
Harrison’s opinion.

....

So . . . to say that there hasn’t been any
evidence with respect to impaired mental
condition that’s been introduced to the jury I
don’t think its accurate.

I think that . . . there’s certainly evidence that
has already been introduced that is consistent
with the defense’s summation of evidence that
would be present that goes precisely to that
condition.

So . . . I am struggling here to find . . . how Dr.
Harrison’s conclusions with respect to the
issues raised by the defense would not be
proper rebuttal.

¶ 43 The prosecution replied, arguing that Dr. Harrison’s testimony

was admissible to rebut DeRossett’s mental condition evidence

under section 16-8-107(1)(a) and (1.5)(a).

¶ 44 Consistent with its prior statements, the trial court found that

evidence concerning DeRossett’s mental condition had been

introduced and that the prosecution should have an opportunity to

rebut the evidence. The trial court limited Dr. Harrison’s testimony

to the issues already before the jury including DeRossett’s

intoxication, his brain injury, and Dr. Harrison’s diagnosis.

22
¶ 45 Dr. Harrison testified that the mental condition evaluation is

“a smaller subset of a mental-state-at-the-time-of-the-alleged-

offense evaluation.” He defined a mental condition diagnosis as

“anything from . . . a low-level situation, to something that’s much

more severe in nature that significantly impairs the person’s

functioning, their behavior, their thinking.”

¶ 46 When the prosecution asked for Dr. Harrison’s diagnosis of

DeRossett, defense counsel renewed his previous objection, which

the trial court again overruled. Dr. Harrison stated that he

diagnosed DeRossett “with a severe alcohol use disorder, and an

unspecified personality disorder.”

[PROSECUTION]: With regard to unspecified
personality disorder, explain what that means.

....

[DEFENSE COUNSEL]: Objection, relevance.

TRIAL COURT: Overruled.

DR. HARRISON: When I use the unspecified
personality disorder diagnosis, what I mean by
that is that I didn’t have clear information that
there was a single specific personality disorder
that fit with the information and the — and the
presentation by Mr. DeRossett.

I included unspecified personality disorder
because there were multiple symptoms of

23
multiple personality disorders, including
narcissism, antisocial —

[DEFENSE COUNSEL]: Same objection, Judge,
and previous record.

TRIAL COURT: Overruled.

DR. HARRISON: Antisocial tendencies, and
what’s referred to as borderline personality
disorder tendencies as well.

[PROSECUTION]: With regard to those three
traits, can you explain what you mean by
narcissism, antisocial tendencies, and
borderline traits?

....

[DEFENSE COUNSEL]: Same objection.

TRIAL COURT: Overruled.

DR. HARRISON: Narcissism in — in a nutshell
is a[n] inflated sense of self, inflated ego,
feeling like one needs to be appreciated,
special attention needs to be given to them.
Antisocial functioning, antisocial personality
disorder tendencies are things like
disregarding the rights of others, manipulative,
deceitful, those types of things. Borderline
personality disorder traits include things like
having impulsive responses to the fear [of] or
actual rejection, vacillating quickly between
moods.

. . . [T]he narcissism, antisocial, and borderline
personality tendencies or the symptoms, there
is some overlap between those three.

24
¶ 47 The prosecution then asked Dr. Harrison’s opinion of

DeRossett’s mental condition at the time of the offense. Over

DeRossett’s objection, Dr. Harrison replied:

My opinion of his mental condition around the
time the alleged offense [is] that . . . it was
most likely alcohol intoxication that
contributed to his mental condition around
that time.

Alcohol intoxication can lead to things like
disinhibited anger, meaning anger that you
don’t inhibit, you don’t stop. Aggression.
Mutability, which means quickly changing
moods, happy, sad, angry, et cetera.
Impulsivity.

Those are the types of results from alcohol
intoxication that I think were most likely
contributing to his mental condition around
the time of the alleged offense.

B. Standard of Review and Applicable Law

¶ 48 As previously described, we review a trial court’s evidentiary

rulings for an abuse of discretion. Nicholls, ¶ 17.

¶ 49 As relevant here, section 16-8-107(1)(a) provides:

Except as provided in this subsection (1),
evidence acquired directly or indirectly for the
first time from a communication derived from
the defendant’s mental processes during the
course of a court-ordered examination
pursuant to section 16-8-106[, C.R.S. 2025,]
or acquired pursuant to section 16-8-103.6[,
C.R.S. 2025,] is not admissible against the

25
defendant on the issues raised by a plea of not
guilty, if the defendant is put to trial on those
issues, except to rebut evidence of the
defendant’s mental condition introduced by
the defendant to show incapacity to form a
culpable mental state; and, in such case, that
evidence may be considered by the trier of fact
only as bearing upon the question of capacity
to form a culpable mental state, and the jury,
at the request of either party, must be so
instructed.

¶ 50 Section 16-8-107(1.5)(a) provides:

Except as otherwise provided in this
subsection (1.5), evidence acquired directly or
indirectly for the first time from a
communication derived from the defendant’s
mental processes during the course of a
court-ordered examination pursuant to section
16-8-106 or acquired pursuant to section
16-8-103.6 is admissible only as to the issues
raised by the defendant’s plea of [NGRI], and
the jury, at the request of either party, must be
so instructed; except that, for offenses
committed on or after July 1, 1999, the
evidence is also admissible as to the
defendant’s mental condition if the defendant
undergoes the examination because the
defendant has given notice pursuant to
subsection (3) of this section that the
defendant intends to introduce expert opinion
evidence concerning the defendant’s mental
condition.

¶ 51 Finally, section 16-8-107(3)(b) provides:

Regardless of whether a defendant enters a
plea of [NGRI] pursuant to section 16-8-103,

26
[C.R.S. 2025,] the defendant is not permitted
to introduce evidence in the nature of expert
opinion concerning the defendant’s mental
condition without having first given notice to
the court and the prosecution of the
defendant’s intent to introduce the evidence
and without having undergone a court-ordered
examination pursuant to section 16-8-106. A
defendant who places the defendant’s mental
condition at issue by giving such notice waives
any claim of confidentiality or privilege as
provided in section 16-8-103.6. The notice
must be given at the time of arraignment;
except that the court, for good cause shown,
shall permit the defendant to inform the court
and prosecution of the intent to introduce
such evidence at any time prior to trial.

C. Analysis

¶ 52 We agree with the People that, despite the prosecutor’s citation

to it at trial, section 16-8-107(1)(a) is not applicable in this case.

Section 16-8-107(1)(a) governs the admissibility of evidence

acquired during the course of a court-ordered examination and

limits such evidence to the defendant’s capacity to form a culpable

mental state. Here, DeRossett initially pleaded NGRI but later

withdrew that plea and proceeded with a mental condition defense.

At trial, he did not contend that he lacked the capacity to form the

requisite mental state. Therefore, subsection (1)(a) does not apply.

See People v. Herdman, 2012 COA 89, ¶ 27 (“[The defendant]

27
withdrew his plea of [NGRI, and] [a]ccordingly, section

16-8-107(1)(a), . . . triggered by claims of insanity, as currently

defined, do[es] not apply.”).

¶ 53 Because DeRossett withdrew his NGRI plea, this case pertains

to the broader “mental condition” described in section

16-8-107(3)(b) and permitted by section 16-8-107(1.5)(a). See

People v. Flippo, 159 P.3d 100, 104 (Colo. 2007) (section

16-8-107(3)(b) is “meant to apply in those situations where insanity

is not the reason the evidence is being introduced”).

¶ 54 Under sections 16-8-107(1.5)(a) and 16-8-107(3)(b), Dr.

Harrison’s testimony was properly admitted to rebut the mental

condition evidence introduced by DeRossett related to his previous

brain injury. DeRossett’s counsel articulated the defense’s theory of

the case in his opening statement by describing the motorcycle

accident and the resulting injuries’ lingering effects, including

processing issues, difficulty communicating, and difficulty

processing his own and other people’s emotions. During the

cross-examination of multiple prosecution witnesses, counsel

referenced DeRossett’s scar from the accident and elicited evidence

that DeRossett seemed confused in early interactions with police.

28
Dr. Harrison’s rebuttal testimony provided an alternate explanation

for DeRossett’s mental state at the time of and immediately

following the offense. Therefore, Dr. Harrison’s mental condition

diagnosis directly rebutted DeRossett’s brain injury evidence. See

Herdman, ¶ 49 (“[E]vidence of Herdman’s psychopathy was relevant

to rebut his contention that his conduct was due to involuntary

intoxication, because such evidence offered an alternative

explanation for his conduct.”).

¶ 55 Additionally, we are not persuaded that the prosecution was

precluded from calling Dr. Harrison simply because the defense did

not call an expert witness first. As DeRossett concedes, he provided

notice of his intent to introduce expert witness opinion testimony

about his mental condition under subsection (3)(b) — a

precondition to the prosecution’s ability to introduce evidence

under subsection (1.5)(a). His later decision to present the mental

condition evidence through lay witness testimony, as permitted by

section 16-8-109, C.R.S. 2025, did not preclude the prosecution

from rebutting that lay testimony with expert testimony, and he

provides no legal authority that would support such a conclusion.

29
¶ 56 We are similarly unpersuaded that the Herdman case requires

a different result simply because it involved evidence rebutting an

affirmative defense (involuntary intoxication) rather than a traverse

(voluntary intoxication). DeRossett does not explain why that

difference produces a different outcome, so we do not address the

issue further. See People v. Cuellar, 2023 COA 20, ¶ 44 (we do not

address undeveloped arguments).

¶ 57 We disagree with DeRossett’s contention that Dr. Harrison’s

testimony was irrelevant because his diagnosis was that

DeRossett’s mental condition at the time of the homicide was

affected by alcohol intoxication and was not “in any way affected by

negative personality traits.” Dr. Harrison testified that the mental

condition evaluation was a subset of the “mental-state-at-the-time-

of-the-alleged-offense” evaluation and said a mental condition

diagnosis ranged from interfering with a person’s functioning to

significantly impairing a person’s functioning. Cf. Herdman, ¶ 59

(concluding admission of bond examiner’s testimony was error

when his assessment was not designed to analyze the defendant’s

mental state at the time of the offense). Indeed, Dr. Harrison

opined that DeRossett’s mental condition was affected by alcohol

30
intoxication, disinhibited anger, aggression, mutability, and

impulsivity. Moreover, DeRossett gave the 911 operator and the

police inconsistent accounts of what had occurred and what he

remembered, which is indicative of both alcohol intoxication and

the deceit and manipulation traits of unspecified personality

disorder.

¶ 58 Merely because Dr. Harrison opined that DeRossett’s mental

condition was affected by alcohol consumption does not negate his

mental condition diagnosis. To the extent that DeRossett argues

that the mental condition diagnosis did not exist or affect his

mental condition at the time of Jackson’s death, there was evidence

contradicting this assertion, and it was for the jury to decide the

conflicting evidence before it. See People v. Jaramillo, 183 P.3d 665,

670 (Colo. App. 2008) (in a criminal case it is the fact finder’s job to

resolve disputes in evidence).

¶ 59 We are not persuaded otherwise by DeRossett’s reliance on

State v. Miner, 657 S.W.2d 332, 333 (Mo. Ct. App. 1983). In Miner,

the Missouri Court of Appeals held that the trial court erroneously

admitted the prosecution’s rebuttal testimony that the defendant

suffered from antisocial personality disorder because it was not

31
relevant to whether the defendant was intoxicated. Here, there was

no dispute that DeRossett was intoxicated. Therefore, Miner is

distinguishable.

¶ 60 Finally, we conclude that the probative value of the rebuttal

evidence was not outweighed by the danger of unfair prejudice

because Dr. Harrison’s opinion confirmed DeRossett’s defense

theory that he was intoxicated and that his intoxication was the

primary driver of DeRossett’s mental state at the time of the offense.

Moreover, the fact that Dr. Harrison could not definitively diagnose

DeRossett with a specific personality disorder shows that any

disorder’s existence was less than well established. And the fact

that the jury convicted DeRossett of the lesser included offense of

second degree murder shows that it carefully considered the mental

condition evidence. See Martin v. People, 738 P.2d 789, 795-796

(Colo. 1987).

¶ 61 Accordingly, we discern no abuse of discretion in the

admission of this evidence.

32
IV. Jury Instruction

¶ 62 DeRossett next contends that the trial court erred by not

giving a limiting instruction regarding Dr. Harrison’s mental

condition evidence. Again, we disagree.

A. Additional Background

¶ 63 DeRossett tendered the following jury instruction:

You may consider evidence of Mr. DeRossett’s
mental health condition, or mental condition
at the time of the commission of the offense in
conjunction with the evidence of intoxication
in determining whether or not the elements of
‘after deliberation and with intent’, ‘knowingly’,
‘recklessly’, and ‘with criminal negligence’ have
been proven to your individual satisfaction
beyond a reasonable doubt.

Additionally, you may consider Mr. DeRossett’s
mental health condition, or mental condition
as it relates to self-defense.

¶ 64 The prosecutor objected to the instruction, arguing,

[T]o me this reads inaccurate as the
intoxication — the jury’s instruction you may
not consider evidence of self-induced
intoxication for the purposes of deciding
whether the prosecution has proved the
elements of murder in the second degree,
manslaughter, or criminally negligent
homicide. So to me this reads as inaccurate,
when going through those mental states.

It improperly highlights certain evidence. The
defenses and COLJI provide[] certain

33
instructions as it goes to intoxication and
self-defense. NGRI was not pled here, so
there’s no instruction in that regard. And I do
believe that it is confusing.

¶ 65 The trial court rejected the proposed instruction, stating that

it “confuse[d] and conflate[d] . . . the separate and distinct purposes

for which the evidence [wa]s admissible.”

¶ 66 After defense counsel amended the instruction, he argued,

[T]here are two separate defenses that I’ve tried
to parse out in the supplemental instruction
that I sent to your clerk and the prosecution,
and what I do in this second attempt is identify
mental health or mental condition evidence,
and the fact that the jury can consider that in
determining whether or not the — the mens
rea elements have been met or proven to their
satisfaction.

¶ 67 Again, the prosecution objected. The trial court rejected the

amended instruction.2

B. Standard of Review and Applicable Law

¶ 68 A trial court has a duty to properly instruct the jury on the

applicable law. People v. Jones, 2018 COA 112, ¶ 24. We review de

novo whether the trial court’s instructions, when read as a whole,

2 The amended instruction is not in the record on appeal, so our

review is limited to defense counsel’s proffered explanation of the
instruction.

34
correctly instructed the jury on the controlling law. Tibbels v.

People, 2022 CO 1, ¶ 22. But we review “a trial court’s decision to

give, or not to give, a particular jury instruction for an abuse of

discretion.” People v. Payne, 2019 COA 167, ¶ 16.

¶ 69 “Statutory interpretation is a question of law we review de

novo.” A.S. v. People, 2013 CO 63, ¶ 10. When interpreting a

statute, our primary purpose is to ascertain and give effect to the

intent of the legislature. People v. Market, 2020 COA 90, ¶ 16. We

assume that the intent of the legislature “has been expressed in the

chosen language.” People v. Coleman, 2018 COA 67, ¶ 41. We look

first to the statute’s language and seek “to give its words and

phrases their plain and ordinary meanings.” Market, ¶ 16.

Statutory words and phrases are read in context and construed

“according to the rules of grammar and common usage.” McCoy v.

People, 2019 CO 44, ¶ 37. “We must construe the statute so as to

give effect to every word, and we may not adopt a construction that

renders any term superfluous or meaningless.” People v. Rice, 2015

COA 168, ¶ 12. If the statute is clear and unambiguous, we look no

further and apply the statute as written. People v. Sullivan, 53 P.3d

1181, 1182 (Colo. App. 2002).

35
¶ 70 Section 16-8-107(1)(a), relied on by DeRossett, requires the

court to instruct the jury, “at the request of either party,” that

evidence from the court-ordered sanity evaluation “may be

considered by the trier of fact only as bearing upon the question of

capacity to form a culpable mental state.” But subsection (1.5)(a),

applicable to a mental condition defense, contains no such

requirement.

C. Analysis

¶ 71 In examining the plain language of the statute, we conclude

that section 16-8-107(1)(a) applies only when a defendant has

entered a plea of NGRI and evidence from a court-ordered

examination is introduced at trial. The record here shows that

DeRossett withdrew his NGRI defense before trial. Thus, his

reliance on subsection (1)(a) is misplaced. Instead, subsections

(1.5)(a) and (3)(b), which govern mental condition evidence, do not

require the court to provide a limiting instruction.

¶ 72 Moreover, DeRossett’s proposed instruction did not address

the jury’s use of evidence from the court-ordered evaluation and did

not seek to limit consideration of that evidence to his mental

condition. Instead, DeRossett endeavored to inform the jury that it

36
could use the mental condition evidence presented, along with

evidence of his intoxication, to determine the mens rea for all levels

of homicide and self-defense.

¶ 73 Moreover, DeRossett’s tendered instruction did not comport

with the law because, as the prosecution argued, it would have

permitted the jury to consider self-induced intoxication as a defense

to the knowingly mental state element of second degree murder.

See People v. Stone, 2020 COA 23, ¶5 (evidence of self-induced

intoxication is not admissible to negate the culpability element of

knowingly); see also People v. Gonzales-Quevedo, 203 P.3d 609, 612

(Colo. App. 2008) (we can affirm on any basis supported by the

record).

¶ 74 Further, we are not convinced that CRE 105, which directs

courts to provide a limiting instruction upon request, requires a

different result. DeRossett never raised CRE 105 or argued it as a

basis for his request, so the court never considered it. Instead, the

court exercised its discretion to reject two proposed instructions

that did not comport with the law. And because they were not

theory of the defense instructions, the court was under no

37
obligation to assist counsel in formulating an appropriate

instruction.

¶ 75 Finally, even assuming the court erred, we conclude that any

error was harmless because DeRossett admitted killing the victim,

and, despite the absence of a limiting instruction, the jury convicted

him of the lesser included offense.

V. Cumulative Error

¶ 76 The cumulative error doctrine applies when “the cumulative

effect of [multiple] errors and defects substantially affected the

fairness of the trial proceedings and the integrity of the fact-finding

process.” Howard-Walker v. People, 2019 CO 69, ¶ 24 (quoting

People v. Lucero, 615 P.2d 660, 666 (Colo. 1980)).

¶ 77 Because we have identified only one error, we conclude no

cumulative error occurred.

VI. Disposition

¶ 78 The judgment is affirmed.

JUDGE BROWN and JUDGE SCHUTZ concur.

38