The opinion
J-S37036-23
2024 PA Super 70
COMMONWEALTH OF PENNSYLVANIA : IN THE SUPERIOR COURT OF
: PENNSYLVANIA
:
v. :
:
:
THOMAS W. NESTOR :
:
Appellant : No. 460 EDA 2023
Appeal from the Judgment of Sentence Entered February 13, 2023
In the Court of Common Pleas of Chester County Criminal Division at
No(s): CP-15-CR-0002107-2022
BEFORE: BENDER, P.J.E., MURRAY, J., and SULLIVAN, J.
DISSENTING OPINION BY BENDER, P.J.E.: FILED APRIL 10, 2024
I respectfully dissent as I agree with Appellant that the Commonwealth
did not present sufficient evidence to establish that his impairment was caused
by a drug or combination of drugs. Under these facts, where there is no
circumstantial evidence of drug usage, I conclude that expert testimony was
required and would discharge Appellant’s conviction for driving under the
influence (DUI).
The conviction at issue requires proof that Appellant was “under the
influence of a drug or combination of drugs to a degree which impairs the
individual’s ability to safely drive….” 75 Pa.C.S. § 3802(d)(2). The
Commonwealth relied on Trooper Nathan Zimmerman’s observations to meet
its burden. The trooper explained that, after pulling Appellant over for some
erratic driving, he asked Appellant to perform field sobriety tests due to
Appellant’s “mood swings, his agitation, [and being] extremely talkative the
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whole time…. He complained of a dry mouth on numerous occasions.” N.T.,
11/2/22, at 24. During the field sobriety tests, the trooper noted that
Appellant’s pupils were dilated. Trooper Zimmerman then conducted
Advanced Roadside Impaired Driving Enforcement (ARIDE) tests. Trooper
Zimmerman was not qualified as an expert in this area, and he testified that
he merely received training on how to perform the ARIDE tests, which are
“about common drugs that are used and abused, [and] indicators that
different drugs can show.” Id. at 35. Trooper Zimmerman testified that
Appellant’s eyes showed no indicators of impairment. Appellant also
performed the Modified Romberg Balance Test. The trooper testified that
during this test, he looks “for tremors in their eyelids or their extremities and
… for swaying of the body.” Id. at 36-37. The Commonwealth then asked
Trooper Zimmerman what indicators of impairment he observed during that
test, and Appellant objected on the basis that this called for expert testimony.
Id. at 37. The trial court overruled the objection, and Trooper Zimmerman
then explained that Appellant’s eyelids “had severe tremors and that his arms
and his hands were twitching….” Id. at 40. The trooper believed that
Appellant was acting “the way that someone that’s impaired by some sort of
stimulant acts.” Id. at 42. Appellant again objected, arguing that such a
conclusion required expert testimony. The Commonwealth replied that the
witness was not offering an expert opinion and was merely testifying to “his
personal observation of interacting with people who he knows to be under the
influence of a stimulant.” Id. The trial court overruled the objection.
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Expert testimony is not per se required to convict a driver of violating
Section 3802(d)(2). Commonwealth v. Griffith, 32 A.3d 1231, 1233 (Pa.
2011). By the same token, the Commonwealth may, in some circumstances,
need to present expert testimony. Id. at 1238 (“We do not dispute that in
some cases, depending on the specific facts and circumstances, expert
testimony may be helpful, or perhaps even necessary, to prove causation
under subsection 3802(d)(2)….”). This is one of those cases.
In this regard, Appellant’s issues effectively overlap. The first issue
claims that the trial court improperly relied on Trooper Zimmerman’s lay
testimony, and the second and third issues assert that the evidence was
insufficient to convict beyond a reasonable doubt in the absence of expert
testimony. I therefore discuss the issues collectively.
In response to Appellant’s objection that expert testimony was needed
to discuss indicators of impairment, the Commonwealth stated that it did not
intend for Trooper Zimmerman to opine that Appellant was under the influence
of a specific controlled substance. See N.T., 11/2/22, at 38-39 (“I’m not going
to ask him to render an opinion on what, if anything, [Appellant] was under
the influence of.”). The Commonwealth told the court that it sought to merely
have the trooper testify as to his perceptions. The Commonwealth argues
that Trooper Zimmerman’s lay testimony was properly admitted for these
reasons, explaining:
As the trooper testified, his job places him in a lot of different
situations with impaired individuals. Particular to this case, the
trooper testified to his observations of individuals he has
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encountered that have been impaired due to controlled substance
stimulant use and described those individuals to be talkative,
agitated, complaining of dry mouth, dilated pupils, and to have
mood swings. All the same observations that Trooper Zimmerman
noted that [Appellant] displayed during his interactions with him.
After laying this foundation, Trooper Zimmerman expressed his
belief that [Appellant] was under the influence of a controlled
substance stimulant and that this impaired his ability to drive
safely.
Commonwealth’s Brief at 19.
I agree that Trooper Zimmerman could offer an opinion that Appellant
was impaired. However, the statute requires that the Commonwealth
establish that said impairment was caused by a drug or combination of drugs,
and I conclude that, in this case, expert testimony was required.
The Majority concludes that “[t]he totality of Trooper Zimmerman’s
observations, taking into account his relevant training and experience,
permitted the admission of his lay opinion under Pa.R.E. 701.” Maj. Op. at
13.1 My learned colleagues conflate evidence of impairment with evidence of
causation. I agree that Trooper Zimmerman could testify to his lay opinion
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1 The Majority declares that our courts “have generally agreed with federal
courts that a witness with the requisite observations and experience may offer
a lay opinion to establish DUI – controlled substance impairment under section
3802(d)(2).” Maj. Op. at 9. Whether our law aligns with federal law on this
issue is beyond the scope of the issues as presented. Additionally,
Pennsylvania Rule of Evidence 702 (“Testimony by Expert Witnesses”),
“differ[s] from F.R.E. 702 in that Pa.R.E. 702(a) and (b) impose the
requirement that the expert’s scientific, technical, or other specialized
knowledge is admissible only if it is beyond that possessed by the average
layperson.” Pa.R.E. 702. I do not see any need to opine that federal law is
identical to our law on this specific topic, as existing Pennsylvania law
adequately addresses the issue.
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that Appellant was impaired. What he could not do, as a lay witness, was
opine that the impairment was caused by a drug or combination of drugs. I
conclude that evidence of causation is lacking in this case, and I do not believe
that the additional circumstantial evidence cited by the Majority bridges the
gap.
The inability to link impairment to a specific drug2 is not a novel problem
and typically arises when a driver, like Appellant here, refuses chemical
testing. However, I submit that cases in which this Court has held that expert
testimony was not needed to convict under Section 3802(d)(2) tend to involve
direct or circumstantial evidence of a particular drug. Typically, those are (1)
an admission; (2) blood or urine tests revealing the presence of those
substances; and/or (3) use paraphernalia or the actual drugs. Our decision
in Commonwealth v. DiPanfilo, 993 A.2d 1262 (Pa. Super. 2010), is
illustrative. The driver in that case admitted “that he had cocaine metabolites
and opiates in his urine, but argue[d] that this evidence [could not] be
scientifically linked to any impairment.” Id. at 1264 (footnote omitted). We
concluded that “the intoxicating effects of cocaine and opiates, like the
intoxicating effects of alcohol, are … widely and commonly understood….” Id.
at 1267. Thus, expert testimony was not needed due to the objective evidence
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2 The statutory reference to “drug” in Section 3802(d)(2) is not limited to
controlled substances. See Commonwealth v. Roser, 914 A.2d 447, 455–
56 (Pa. Super. 2006) (concluding that “gasoline and bug and tar remover are
drugs under the circumstances of this case”). For ease of reference, I will
refer to “drugs” as a shorthand.
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that the driver had specific drugs in his system combined with the “widely and
commonly understood” effects of those drugs. See also Commonwealth v.
Spence, 290 A.3d 301, 310 (Pa. Super. 2023) (holding that expert testimony
was not needed due to circumstantial evidence; the trooper “immediately
detected the odor of marijuana” and the driver admitted to smoking marijuana
hours before driving).
Our Supreme Court’s decision in Griffith, which overruled this Court’s
holding that expert testimony is required when prescription medications are
at issue, similarly illustrates the importance of establishing that evidence of
impairment was caused by a specific drug. There, the Court explained:
We recognize that the Superior Court appeared to limit its
requirement for expert testimony in subsection 3802(d)(2) cases
to those involving prescription medications as the alleged
intoxicants. This limitation was based on the Superior Court’s
determination that the average layperson does not know or
recognize the effects of prescription medications. We do not
believe that the Superior Court’s division of drugs into prescription
versus non-prescription categories is warranted or helpful in the
interpretation or application of subsection 3802(d)(2) or in the
determination of whether an expert witness should be called.
Pursuant to our general standard, a need for expert testimony
arises when “the jury is confronted with factual issues whose
resolution requires knowledge beyond the ken of the ordinary
layman.” Kozak v. Struth, … 531 A.2d 420, 422 ([Pa.] 1987).
The need for expert testimony in a subsection 3802(d)(2)
prosecution must be evaluated on a case-by-case basis, taking
into account not just the specific drug at issue, prescription or
otherwise, but also the nature and overall strength of the
Commonwealth’s evidence, viewed pursuant to the general
standard expressed in Kozak, supra.
Griffith, 32 A.3d at 1239 (emphasis in original).
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The reference to “the specific drug at issue” demonstrates that the
Commonwealth cannot rely on conjecture, which is consistent with general
principles surrounding sufficiency review. Commonwealth v. Boettcher,
459 A.2d 806, 807 (Pa. Super. 1983) (“It is settled law that while guilt may
be proved by direct or circumstantial evidence, it may not rest upon mere
suspicion or conjecture.”). This Court’s decision in Commonwealth v.
Gause, 164 A.3d 532 (Pa. Super. 2017) (en banc), which Appellant largely
relies upon, drives this point home. In that case, the Commonwealth charged
Gause with driving under the influence of alcohol as well as a controlled
substance. The arresting officer smelled alcohol on Gause’s breath but did not
detect any signs of marijuana usage. During field sobriety tests, Officer Eiker
performed, inter alia, the Romberg Test due to her suspicion that Gause was
under the influence of marijuana. She observed Gause’s eyelids tremoring
and opined that the tremors were associated with marijuana usage. Gause
refused blood testing.
The Gause Court stated, “expert testimony is not necessary to establish
impairment under subsection 3802(d)(2) where there exists other
independent evidence of impairment. In our opinion, the facts and
circumstances of the case before us clearly fall within the ‘expert testimony
necessary’ classification.” Id. at 538. We pointed out that the Commonwealth
“provided no evidence that Gause had recently ingested marijuana.” Id. We
elaborated:
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On the contrary, Officer Eiker testified that Gause had stopped at
a lighted intersection, with his headlights and turn signal properly
activated, and that she stopped him after he had turned and she
saw that his taillights were not illuminated. Officer Eiker testified
that when she activated her lights, Gause properly signaled and
pulled over immediately to the curb. Gause provided his license,
registration and proof of insurance without fumbling. There was
no evidence that an odor of marijuana emanated from his person
or from his vehicle at the time he was stopped. There was no
testimony that Gause’s eyes were bloodshot. Nor did Officer Eiker
testify that she discovered any physical evidence of recent
marijuana usage. Further, there was no admission from Gause
that he had recently smoked marijuana, nor was there eyewitness
testimony to establish recent ingestion of marijuana.
Id. at 538–39 (citations to transcript and footnote omitted).
The Gause Court explained why the officer’s testimony linking eyelid
tremors to marijuana required expert testimony, as follows:
It is clear to this Court that Officer Eiker’s observation of “eyelid
tremors” is not the typical and obvious indicia of marijuana use,
such as the distinct odor of burnt marijuana emanating from the
person or the vehicle. Further, it is eminently clear that attributing
body or eyelid tremors to marijuana use requires specialized
knowledge…. Unlike staggering, stumbling, glassy or bloodshot
eyes, and slurred speech, the “ordinary signs of intoxication
discernable by a layperson,” eye tremors are not an ordinary sign
of ingestion of a controlled substance, in particular, marijuana. As
the trial court acknowledged, Officer Eiker’s testimony as to her
observations did not obviate the necessity of an expert to
explain whether “eye tremors,” or “body tremors,” would indicate
that someone was under the influence of marijuana and that this
impaired his ability to safely drive, in violation of section
3802(d)(2).
Id. at 539 (footnote omitted; all emphasis in original).
Officer Eiker was not qualified to link eyelid tremors to drug usage at
all. Similarly, Trooper Zimmerman could not opine that Appellant’s
impairment was due to the presence of drugs in his system. The Majority
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argues that this is another basis to distinguish Gause, stating, “Critically,
unlike the officer in Gause, ‘Trooper Zimmerman did not voice an opinion as
to which controlled substance he suspected [Appellant] had ingested….’” Maj.
Op. at 15 (quoting trial court opinion; bracketing supplied by Majority).
Gause would be meaningless if the Commonwealth could avoid the need for
expert testimony by instructing police officers to testify that eyelid tremors
are indicative of drug usage. The problem in Gause was not that the officer
linked the behavior to a specific drug; the problem was that the officer was
not qualified to link the behavior to drug usage at all. The same is true here.
Furthermore, the fact that Trooper Zimmerman identified Appellant as
being under the influence of a “controlled substance stimulant” further
highlights the need for expert testimony. As the Gause Court remarked,
behaviors like eye tremors can be caused by a variety of innocent behaviors:
According to the Mayo Clinic, eye tremors, or eye twitches, are
also an indication of stress, bright light, caffeine excess, fatigue,
irritation of the eye surface or inner eyelids, physical exertion,
smoking, wind and alcohol use. Additionally, eye tremors can also
be caused by various medical conditions, including dry eyes,
glaucoma, blepharitis, corneal abrasion, and Tourette’s syndrome.
Gause, 164 A.3d at 539 n.8.
The Gause Court’s analysis signals a belief that the General Assembly
presumably did not intend for, inter alia, caffeine, which is a stimulant, to
qualify as a drug for purposes of the DUI statute. The principle that emerges
from our caselaw is that connecting eyelid tremors and eye twitches to drug
use calls for expert testimony. For the foregoing reasons, I agree with
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Appellant that expert testimony was needed to establish that the signs of
impairment observed by the troopers were attributable to drugs.
Next, the Majority distinguishes Gause on the grounds that Gause
exhibited far more limited signs of impairment than Appellant. However, I do
not agree that the signs of impairment displayed by Appellant were so
circumstantially strong that expert testimony was not needed. I do not
foreclose the possibility that a citizen’s behavior could be so bizarre or
irrational that the Commonwealth is entitled to a rational inference on
sufficiency-of-evidence review that the person must have been “on
something.” I simply conclude that Appellant’s behavior does not rise to that
level. Nor is there any other circumstantial evidence to suggest that
Appellant’s impairment was due to a drug. Significantly, the troopers did not
find any kind of drugs or use paraphernalia in Appellant’s vehicle. Appellant
did not admit to recently ingesting any kind of drug. And the Commonwealth
failed to have a drug recognition expert examine Appellant.3 While Appellant’s
refusal to submit to a blood draw is admissible as evidence, 75 Pa.C.S. §
1547(e), that is not dispositive, as “[n]o presumptions shall arise” from the
refusal, id., and the driver in Gause likewise refused a blood draw.
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3 Trooper Zimmerman testified that he requested a drug recognition expert,
but “[t]here was none available at the time.” N.T., 11/2/22, at 67.
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Finally, the Commonwealth and the Majority rely on the dashcam video
showing Appellant’s driving,4 his mood swings, agitation, and talkative
manner. These are not, in my view, particularly compelling pieces of
circumstantial evidence. Being pulled over is not a pleasant experience, and
mood swings and talkative behavior may simply reflect nervousness or
annoyance. The Majority does not suggest otherwise; instead, my learned
colleagues choose to defer to the trial court’s credibility determinations. Maj.
Op. at 22 (“The trial court found Trooper Zimmerman credible, and Appellant
not credible.”). As I have explained, Trooper Zimmerman was not qualified
to offer an opinion that Appellant’s impairment was caused by a drug.
Therefore, the trial court could not credit Trooper Zimmerman as an expert.
Relatedly, the fact that the trial court did not credit Appellant’s explanation for
his impaired driving does not relieve the Commonwealth of its burden to
establish the elements of the offense beyond a reasonable doubt. “[T]he
Commonwealth cannot sustain its burden of proof solely on the fact finder’s
disbelief of the defendant’s testimony. The disbelief of a denial does not,
taken alone, afford affirmative proof that the denied fact existed so as to
satisfy a proponent’s burden of proving that fact.” Commonwealth v.
Torres, 766 A.2d 342, 345 (Pa. 2001) (quotation marks and citation omitted).
Appellant was not required to convince the court that his impairment was
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4 As the trial court opinion relates, Appellant’s vehicle veered over the fog and
center lines. After reviewing the video of Appellant’s driving and his field
sobriety tests, I do not conclude that Appellant’s behavior was so erratic that
the Commonwealth was entitled to a rational inference that he was on drugs.
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attributable to an innocent explanation. On the contrary, the Commonwealth
was required to prove beyond a reasonable doubt that his impairment was
caused by a drug. Because the Commonwealth failed to do so under these
circumstances, I would discharge Appellant’s DUI conviction.
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