23CA0340 Peo v Turner 04-03-2025
COLORADO COURT OF APPEALS
Court of Appeals No. 23CA0340 Garfield County District Court No. 20CR356 Honorable James B. Boyd, Judge
The People of the State of Colorado,
Plaintiff-Appellee,
v.
Jeffrey H. Turner,
Defendant-Appellant.
JUDGMENT AFFIRMED
Division II Opinion by JUDGE LUM Fox and Gomez, JJ., concur
NOT PUBLISHED PURSUANT TO C.A.R. 35(e) Announced April 3, 2025
Philip J. Weiser, Attorney General, Emmy A. Langley, Senior Assistant Attorney General, Denver, Colorado, for Plaintiff-Appellee
Daniel Kent, Alternate Defense Counsel, Denver, Colorado, for Defendant- Appellant ¶1 Defendant, Jeffrey H. Turner, appeals his conviction for
driving under the influence (DUI) – fourth or subsequent offense.
We affirm.
I. Background
¶2 On May 8, 2020, Trooper Charles Hiller initiated a traffic stop
on I-70 of a black Rav 4 traveling at ninety-three miles per hour.
The vehicle moved into the right lane and exited the interstate for
the stop. Trooper Hiller spoke to Turner, who was driving the
vehicle. He noted that Turner had glassy eyes and that a strong
odor of marijuana was present inside the vehicle. Trooper Hiller
asked Turner if he had consumed marijuana. Turner said he had
smoked a joint and a “dab”1 earlier that day.
¶3 Trooper Hiller asked Turner to exit the vehicle and noted the
smell of marijuana on his breath and a green residue on his tongue.
He then administered voluntary field sobriety tests. Based on the
results of the tests, Trooper Hiller believed Turner to be impaired
and arrested him. Trooper Hiller found marijuana and marijuana
1 At trial, Trooper Hiller testified, “A dab is usually like a pipe with
marijuana concentrate or like wax or like the oily substance that is marijuana . . . heated up and smoked.”
1 paraphernalia during a search of Turner’s car. Turner was
informed of Colorado’s express consent laws and agreed to a blood
test, after which he was taken to a hotel room for the evening.2
¶4 Turner was charged with DUI – fourth or subsequent offense;
speeding; no proof of insurance; illegal use, possession, or
consumption of marijuana in a vehicle; and illegal possession or
consumption of alcohol in a vehicle. A jury found him guilty as
charged. Turner was sentenced to two years in the Department of
Corrections for the DUI conviction with a concurrent thirty days in
jail for the proof of insurance conviction, and the court imposed
various fines.
¶5 Turner appeals his conviction for DUI.
II. Expert Testimony
¶6 Turner first contends that the trial court erred by permitting
Trooper Hiller’s testimony about the administration and
interpretation of certain standardized field sobriety tests (SFSTs)
and tests learned through the Advanced Roadside Impaired Driving
2 Trooper Hiller transported Turner to a hotel rather than to jail
because of the jail’s COVID restrictions and because Turner had several live reptiles in the car when he was pulled over.
2 Enforcement (ARIDE) course (collectively, roadside maneuvers). We
disagree.
A. Additional Facts
¶7 At trial, the prosecution elicited the following testimony from
Trooper Hiller.
¶8 Trooper Hiller had been employed in law enforcement from
2005 to 2020. Over the course of his career, he conducted more
than 500 DUI investigations.
¶9 As part of his training and education, Trooper Hiller had taken
courses on detecting impaired driving and drug symptomology,
including the administration and interpretation of roadside
maneuvers. He had also observed the effects of marijuana on the
performance of roadside maneuvers during “green labs.”3
¶ 10 The SFSTs consist of the horizontal gaze nystagmus (HGN),
vertical gaze nystagmus (VGN), walk-and-turn, and one-legged
stand tests. Turner’s performance on the HGN and VGN tests
didn’t indicate that he was impaired, but Trooper Hiller informally
observed that he wasn’t able to follow instructions during
3 In a green lab, participants consume marijuana, and officers
administer roadside maneuvers to observe their performance.
3 administration of the HGN test. Turner also didn’t “ma[ke] it past
the instruction phase” of the walk-and-turn test, and he
demonstrated impairment on the one-legged stand test.
¶ 11 Trooper Hiller also administered two ARIDE maneuvers — the
modified Romberg test (measuring a person’s internal clock) and the
lack of convergence test (measuring a person’s ability to converge
their eyes to specific point). Turner performed just outside the
normal range on the modified Romberg test, indicating impairment.
His performance on the lack of convergence test is unclear from the
record.
¶ 12 Given Turner’s overall performance on the roadside maneuvers
and the other observations Trooper Hiller made during the stop,
Trooper Hiller believed Turner was impaired.
B. Standard of Review and Applicable Law
¶ 13 Because Turner didn’t object to any of Trooper Hiller’s
testimony, we review for plain error. See Hagos v. People, 2012 CO
63, ¶ 14. Plain error occurs when the error is obvious and “so
undermines the fundamental fairness of the trial itself as to cast
serious doubt on the reliability of the judgment of conviction.”
Cardman v. People, 2019 CO 73, ¶ 19.
4 ¶ 14 A lay witness’s testimony is limited to opinions or inferences
that are (1) “rationally based on the perception of the witness”;
(2) “helpful to a clear understanding of the witness’ testimony or the
determination of a fact in issue”; and (3) “not based on scientific,
technical, or other specialized knowledge within the scope of [CRE]
702.” CRE 701.
¶ 15 Conversely, “if scientific, technical, or other specialized
knowledge will assist the trier of fact to understand the evidence or
to determine a fact in issue, a witness qualified as an expert by
knowledge, skill, experience, training, or education, may testify
thereto in the form of an opinion or otherwise.” CRE 702. A court
may not admit expert testimony under the guise of lay opinion.
Venalonzo v. People, 2017 CO 9, ¶ 31.
C. Analysis
¶ 16 Turner contends that Trooper Hiller’s testimony about the
VGN, HGN, lack of convergence, and modified Romberg tests, as
well as his testimony about Turner’s impairment based on the
results of those tests, was inadmissible because it was expert
testimony in the guise of lay testimony.
5 ¶ 17 We agree that at least some of Trooper Hiller’s testimony was
expert testimony. See Campbell v. People, 2019 CO 66, ¶ 31
(holding that the administration and interpretation of the HGN test
is expert testimony). Nevertheless, we conclude that the court
didn’t err by admitting it. A party calling an expert witness need
not formally offer, and the trial court need not formally accept, the
witness as an expert to admit the expert’s testimony so long as the
testimony meets the requirements of CRE 702 and is based on
generally reliable scientific principles4 as set forth in People v.
Shreck, 22 P.3d 68, 78-79 (Colo. 2001). People v. Martinez, 2024
CO 69, ¶¶ 27-36.5
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23CA0340 Peo v Turner 04-03-2025
COLORADO COURT OF APPEALS
Court of Appeals No. 23CA0340 Garfield County District Court No. 20CR356 Honorable James B. Boyd, Judge
The People of the State of Colorado,
Plaintiff-Appellee,
v.
Jeffrey H. Turner,
Defendant-Appellant.
JUDGMENT AFFIRMED
Division II Opinion by JUDGE LUM Fox and Gomez, JJ., concur
NOT PUBLISHED PURSUANT TO C.A.R. 35(e) Announced April 3, 2025
Philip J. Weiser, Attorney General, Emmy A. Langley, Senior Assistant Attorney General, Denver, Colorado, for Plaintiff-Appellee
Daniel Kent, Alternate Defense Counsel, Denver, Colorado, for Defendant- Appellant ¶1 Defendant, Jeffrey H. Turner, appeals his conviction for
driving under the influence (DUI) – fourth or subsequent offense.
We affirm.
I. Background
¶2 On May 8, 2020, Trooper Charles Hiller initiated a traffic stop
on I-70 of a black Rav 4 traveling at ninety-three miles per hour.
The vehicle moved into the right lane and exited the interstate for
the stop. Trooper Hiller spoke to Turner, who was driving the
vehicle. He noted that Turner had glassy eyes and that a strong
odor of marijuana was present inside the vehicle. Trooper Hiller
asked Turner if he had consumed marijuana. Turner said he had
smoked a joint and a “dab”1 earlier that day.
¶3 Trooper Hiller asked Turner to exit the vehicle and noted the
smell of marijuana on his breath and a green residue on his tongue.
He then administered voluntary field sobriety tests. Based on the
results of the tests, Trooper Hiller believed Turner to be impaired
and arrested him. Trooper Hiller found marijuana and marijuana
1 At trial, Trooper Hiller testified, “A dab is usually like a pipe with
marijuana concentrate or like wax or like the oily substance that is marijuana . . . heated up and smoked.”
1 paraphernalia during a search of Turner’s car. Turner was
informed of Colorado’s express consent laws and agreed to a blood
test, after which he was taken to a hotel room for the evening.2
¶4 Turner was charged with DUI – fourth or subsequent offense;
speeding; no proof of insurance; illegal use, possession, or
consumption of marijuana in a vehicle; and illegal possession or
consumption of alcohol in a vehicle. A jury found him guilty as
charged. Turner was sentenced to two years in the Department of
Corrections for the DUI conviction with a concurrent thirty days in
jail for the proof of insurance conviction, and the court imposed
various fines.
¶5 Turner appeals his conviction for DUI.
II. Expert Testimony
¶6 Turner first contends that the trial court erred by permitting
Trooper Hiller’s testimony about the administration and
interpretation of certain standardized field sobriety tests (SFSTs)
and tests learned through the Advanced Roadside Impaired Driving
2 Trooper Hiller transported Turner to a hotel rather than to jail
because of the jail’s COVID restrictions and because Turner had several live reptiles in the car when he was pulled over.
2 Enforcement (ARIDE) course (collectively, roadside maneuvers). We
disagree.
A. Additional Facts
¶7 At trial, the prosecution elicited the following testimony from
Trooper Hiller.
¶8 Trooper Hiller had been employed in law enforcement from
2005 to 2020. Over the course of his career, he conducted more
than 500 DUI investigations.
¶9 As part of his training and education, Trooper Hiller had taken
courses on detecting impaired driving and drug symptomology,
including the administration and interpretation of roadside
maneuvers. He had also observed the effects of marijuana on the
performance of roadside maneuvers during “green labs.”3
¶ 10 The SFSTs consist of the horizontal gaze nystagmus (HGN),
vertical gaze nystagmus (VGN), walk-and-turn, and one-legged
stand tests. Turner’s performance on the HGN and VGN tests
didn’t indicate that he was impaired, but Trooper Hiller informally
observed that he wasn’t able to follow instructions during
3 In a green lab, participants consume marijuana, and officers
administer roadside maneuvers to observe their performance.
3 administration of the HGN test. Turner also didn’t “ma[ke] it past
the instruction phase” of the walk-and-turn test, and he
demonstrated impairment on the one-legged stand test.
¶ 11 Trooper Hiller also administered two ARIDE maneuvers — the
modified Romberg test (measuring a person’s internal clock) and the
lack of convergence test (measuring a person’s ability to converge
their eyes to specific point). Turner performed just outside the
normal range on the modified Romberg test, indicating impairment.
His performance on the lack of convergence test is unclear from the
record.
¶ 12 Given Turner’s overall performance on the roadside maneuvers
and the other observations Trooper Hiller made during the stop,
Trooper Hiller believed Turner was impaired.
B. Standard of Review and Applicable Law
¶ 13 Because Turner didn’t object to any of Trooper Hiller’s
testimony, we review for plain error. See Hagos v. People, 2012 CO
63, ¶ 14. Plain error occurs when the error is obvious and “so
undermines the fundamental fairness of the trial itself as to cast
serious doubt on the reliability of the judgment of conviction.”
Cardman v. People, 2019 CO 73, ¶ 19.
4 ¶ 14 A lay witness’s testimony is limited to opinions or inferences
that are (1) “rationally based on the perception of the witness”;
(2) “helpful to a clear understanding of the witness’ testimony or the
determination of a fact in issue”; and (3) “not based on scientific,
technical, or other specialized knowledge within the scope of [CRE]
702.” CRE 701.
¶ 15 Conversely, “if scientific, technical, or other specialized
knowledge will assist the trier of fact to understand the evidence or
to determine a fact in issue, a witness qualified as an expert by
knowledge, skill, experience, training, or education, may testify
thereto in the form of an opinion or otherwise.” CRE 702. A court
may not admit expert testimony under the guise of lay opinion.
Venalonzo v. People, 2017 CO 9, ¶ 31.
C. Analysis
¶ 16 Turner contends that Trooper Hiller’s testimony about the
VGN, HGN, lack of convergence, and modified Romberg tests, as
well as his testimony about Turner’s impairment based on the
results of those tests, was inadmissible because it was expert
testimony in the guise of lay testimony.
5 ¶ 17 We agree that at least some of Trooper Hiller’s testimony was
expert testimony. See Campbell v. People, 2019 CO 66, ¶ 31
(holding that the administration and interpretation of the HGN test
is expert testimony). Nevertheless, we conclude that the court
didn’t err by admitting it. A party calling an expert witness need
not formally offer, and the trial court need not formally accept, the
witness as an expert to admit the expert’s testimony so long as the
testimony meets the requirements of CRE 702 and is based on
generally reliable scientific principles4 as set forth in People v.
Shreck, 22 P.3d 68, 78-79 (Colo. 2001). People v. Martinez, 2024
CO 69, ¶¶ 27-36.5
¶ 18 To the extent the administration and interpretation of roadside
maneuvers is expert testimony, Trooper Hiller was qualified to give
4 Turner doesn’t suggest that the scientific principles behind
roadside maneuvers are unreliable such that testimony about the administration and results of those tests would be inadmissible under People v. Shreck, 22 P.3d 68 (Colo. 2001). Accordingly, we don’t analyze this component of expert testimony admissibility. 5 Although Turner doesn’t raise any argument about expert
disclosure, we note that the prosecution disclosed Trooper Hiller as an expert in field sobriety tests approximately six months before trial. See People v. Martinez, 2024 CO 69, ¶ 32 (noting that cases ruling that expert testimony was improperly admitted as lay testimony were concerned with absence of pretrial disclosure of expert witnesses).
6 that testimony by his training and experience. Moreover, the
testimony was useful to the jury because whether Turner was
under the influence due to his marijuana usage was the primary
issue disputed at trial. Thus, Trooper Hiller’s testimony was
properly admitted as expert testimony.
¶ 19 Even assuming the court erred, however, the error wasn’t
substantial. The administration and results of the HGN and VGN
tests didn’t prejudice Turner because he didn’t display signs of
impairment under those tests. Likewise, while Trooper Hiller
testified about what the lack of convergence test was designed to
measure, he didn’t testify that Turner demonstrated impairment
during that test.
¶ 20 The only expert testimony that arguably prejudiced Turner
was the testimony about the modified Romberg test and the results
thereof. However, we can’t conclude that the exclusion of this
testimony would have significantly impacted the outcome at trial.
Trooper Hiller’s overall opinion regarding Turner’s impairment was
based not only on the modified Romberg test but also on (1) the
results of the walk-and-turn test (specifically, Turner’s inability to
follow instructions); (2) Turner’s performance on the one-legged
7 stand test; and (3) Trooper Hiller’s informal observations of Turner’s
appearance, comportment, and inability to follow directions.
Turner doesn’t challenge the admissibility of the walk-and-turn or
one-legged stand test testimony on appeal. And to the extent
Trooper Hiller’s opinion was based on informal observations, it
required no expertise. Cf. People v. Souva, 141 P.3d 845, 850 (Colo.
App. 2005) (certified addiction counselor who had “experience
dealing with . . . people who used drugs” could offer lay testimony
that defendant was under the influence when she observed him).
¶ 21 Furthermore, Trooper Hiller’s testimony wasn’t the only
support for Turner’s conviction. The jury also saw video footage of
the roadside maneuvers, parts of which showed that Turner was
unsteady on his feet, confused, and had trouble following Trooper
Hiller’s instructions. And the jury could infer that Turner was
under the influence from the amount of tetrahydrocannabinol (THC)
in his blood. See infra Part III.C.
¶ 22 Accordingly, even if the court erred by admitting the
challenged testimony, its admission doesn’t cast serious doubt on
the reliability of the judgment of conviction. See Cardman, ¶ 19.
8 III. Prosecution’s Repeated Usage of “Legal Limit”
¶ 23 Turner argues that the prosecution misstated the law and
improperly lowered its burden of proof by repeatedly referring to the
five-nanogram-per-milliliter permissive inference set forth in section
42-4-1301(6)(a)(IV), C.R.S. 2024, as the “legal limit” for THC
concentration in the blood while operating a vehicle. We conclude
that any error wasn’t plain.
A. Applicable Law and Standard of Review
¶ 24 In Colorado, a driver who has consumed THC is “[d]riving
under the influence” if the THC renders the driver “substantially
incapable, . . . mentally or physically, . . . to exercise clear
judgment, sufficient physical control, or due care in the safe
operation of a vehicle.” § 42-4-1301(1)(f). If a driver’s blood is
shown to contain “five nanograms or more of delta 9-[THC] per
milliliter . . . such fact gives rise to a permissible inference that the
defendant was under the influence.” § 42-4-1301(6)(a)(IV). A
permissible inference doesn’t shift the burden of proof to the
defendant “but instead allows the trier of fact to find the inferred
fact from the proof of the predicate fact.” People v. Felgar, 58 P.3d
1122, 1124 (Colo. App. 2002).
9 ¶ 25 While an individual whose blood alcohol concentration is 0.08
or more commits DUI per se, no similar “per se” violation exists for
driving under the influence of THC. See § 42-4-1301(2)(a).
¶ 26 “Although a prosecutor may argue all reasonable inferences
from the evidence in the record, [they] may not misstate or
misinterpret the law . . . .” People v. McMinn, 2013 COA 94, ¶ 62
(first citing People v. Cevallos–Acosta, 140 P.3d 116, 122 (Colo. App.
2005); and then citing People v. Walters, 148 P.3d 331, 334 (Colo.
App. 2006)). We review a claim of prosecutorial misconduct in two
steps. People v. Rhea, 2014 COA 60, ¶ 40. We first determine
whether misconduct occurred based on the totality of the
circumstances. Id. If we conclude it did, we determine whether it
warrants reversal according to the proper standard of review. Id.
¶ 27 Because Turner didn’t preserve this issue, we review it for
plain error. See Hagos, ¶ 14
B. Additional Facts
¶ 28 The prosecution presented evidence of Turner’s blood test
results, which showed that he had eighteen nanograms per milliliter
of THC in his blood approximately one hour after he was pulled
over.
10 ¶ 29 Throughout the trial, the prosecution used the terms “legal
limit” or “limit” to describe the five-nanogram-per-milliliter level that
gives rise to a permissible inference of THC intoxication under
Colorado law. For instance, during opening statements, the
prosecution informed the jury, “You will . . . hear, at the close of
evidence, that the limit for [THC] is 5 nanograms. So the defendant
was driving with three times more than the legal limit of marijuana
in his system.” (Emphases added.) And during rebuttal closings,
the prosecutor said:
[T]his defendant thought he was fine, he thought it was okay to get up, have his french toast, smoke a joint and then make a couple of stops, and eight hours later, having traveled approximately 45 miles, be more than three times the legal limit of THC in his system.
(Emphasis added.) All in all, during the opening and rebuttal
closing statements, the prosecution referred to the “limit” or “legal
limit” eleven times.
¶ 30 The term also came up during testimony: The toxicologist who
analyzed Turner’s blood sample said that she was aware that five
nanograms per milliliter was Colorado’s “legal limit” for THC levels
while driving. And during Turner’s cross-examination, the
11 prosecution characterized the five-nanogram permissible inference
level as a “legal limit” five times.
¶ 31 Defense counsel didn’t object to any of these characterizations.
¶ 32 Turner argues that the prosecution’s characterization of the
five-nanogram-per-milliliter threshold as a “legal limit” constituted
misconduct warranting reversal. Specifically, Turner contends that,
by referring to the permissive inference as a “legal limit,” the
prosecution “created an appearance of a rebuttable presumption”
that being over the five-nanogram-per-milliliter threshold was
automatic grounds for conviction, which lowered the prosecution’s
burden of proof. Assuming, without deciding, that the prosecution
erred by using the term “legal limit” and that the error was obvious,
we nevertheless conclude that the error was not substantial in light
of the strength and quantity of the evidence of Turner’s intoxication
presented at trial.
¶ 33 “Plain error occurs only when, after review of the entire record,
the appellate court concludes that the error undermined the
fundamental fairness of the trial.” People v. Miller, 113 P.3d 743,
745 (Colo. 2005). The record reflects that the jury received a
12 written instruction that (1) accurately explained the permissible
inference; (2) informed the jury that the permissible inference
“allows, but does not require, you to find a fact from proof of
another fact or facts, if that conclusion is justified by the evidence
as a whole”; and (3) reminded the jury that the prosecution bore the
burden of proof and that “a permissible inference does not shift that
burden to the defendant.” Moreover, overwhelming evidence
supported Turner’s conviction:
• The jury could infer that Turner was under the influence
based on the concentration of THC in his blood.
• As described in Part II.A, above, Trooper Hiller testified
that he believed Turner was under the influence based on
Turner’s performance on the roadside maneuvers.
• As described in Part II.C, above, the video footage showed
Turner’s uneven performance during the roadside
maneuvers.
• When pulled over, Turner made a wide lane change,
hitting the white lines demarcating the right side of the
lane.
13 • Trooper Hiller observed Turner fumbling with his
identification documents when asked to produce them
and found several marijuana containers and other drug
paraphernalia in his car.
¶ 34 Given the strength of the evidence and the jury instructions,
we cannot conclude that the prosecution’s repeated use of the
phrase “legal limit” casts “serious doubt on the reliability of the
judgment of conviction” in this case. Cardman, ¶ 19. We therefore
discern no plain error.
IV. Limiting Instruction Regarding Prior Conviction Records
¶ 35 On the second day of trial, the prosecution presented certified
records of Turner’s four prior DUI convictions to prove that this was
his fourth or subsequent offense. See People v. Herold, 2024 COA
53, ¶¶ 12-13 (noting that prior convictions are an element of felony
DUI that must be proved beyond a reasonable doubt).
14 ¶ 36 Defense counsel didn’t argue that the records prejudiced
Turner or ask for a limiting instruction,6 and the records were
admitted into evidence.
¶ 37 Turner argues that the court erred by failing to sua sponte
instruct the jury that the evidence of prior convictions could not be
used to prove that he drove under the influence on this occasion.
We disagree.
B. Analysis
¶ 38 We review a trial court’s evidentiary rulings for an abuse of
discretion. Campbell, ¶ 21. A trial court abuses its discretion when
its ruling is manifestly arbitrary, unreasonable or unfair. Id.
Because Turner didn’t request a limiting instruction, we review for
plain error. See People v. Griffin, 224 P.3d 292, 298 (Colo. App.
2009).
¶ 39 We perceive no error because the court was not required to
issue a limiting instruction sua sponte. See id. at 298-99. Absent a
special statutory requirement or a timely request by either party to
instruct the jury on the limited purpose of a particular piece of
6 Defense counsel objected (and was overruled) on other grounds
not relevant to this appeal.
15 evidence, a court is not required to give a limiting instruction. Id.
Instead, “[a]s a general rule, defense counsel is charged with the
task of deciding whether a limiting instruction is desirable.” Id. at
298.
V. Cumulative Error
¶ 40 Finally, Turner contends that the combined effect of the
foregoing alleged errors warrants reversal of his conviction.
¶ 41 “The doctrine of cumulative error requires that numerous
errors be committed, not merely alleged.” People v. Conyac, 2014
COA 8M, ¶ 152. Under the cumulative error standard, a conviction
will be reversed only if the aggregate impact of any errors
substantially prejudiced a defendant’s right to a fair trial. Id.
¶ 42 Here, we assumed one trial error with respect to Turner’s
claim that the prosecution committed misconduct by continually
utilizing the phrase “legal limit,” but we perceived no error on the
expert testimony and limiting instruction contentions. Because we
do not discern more than one trial error in this case, cumulative
error is inapplicable. See id.
16 VI. Disposition
¶ 43 The judgment of conviction for DUI – fourth or subsequent
offense is affirmed. The portions of the judgment not affected by
this appeal remain undisturbed.
JUDGE FOX and JUDGE GOMEZ concur.