Bruce Bunting and Jessie Brinkley v. District of Columbia Cvs Pharmacy, LLC

United States Court of Appeals
FOR THE DISTRICT OF COLUMBIA CIRCUIT
Argued September 19, 2025 Decided April 14, 2026
No. 24-7124
BRUCE BUNTING AND JESSIE BRINKLEY,
APPELLANTS
v.
DISTRICT OF COLUMBIA CVS PHARMACY, LLC,
APPELLEE
Appeal from the United States District Court
for the District of Columbia
(No. 1:22-cv-00766)
Jacob M. Lebowitz argued the cause and filed the briefs for
appellants.
Jessica L. Smith argued the cause for appellee. With her
on the brief were Matthew W. Naparty and Diane V. D’Aiutolo.
Alexandra M. Monteforte entered an appearance.
Before: HENDERSON and RAO, Circuit Judges, and
EDWARDS, Senior Circuit Judge.
Opinion for the Court filed by Circuit Judge RAO.
Concurring opinion filed by Circuit Judge HENDERSON.

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RAO, Circuit Judge: In this slip and fall case, the district
court granted summary judgment to CVS. Because the
plaintiffs created a genuine issue of material fact as to whether
the walkway outside the store was dangerously slippery, we
reverse the grant of summary judgment on plaintiffs’
negligence claim. We affirm, however, summary judgment for
CVS on the negligence per se claim. Accordingly, we vacate
in part and remand for further proceedings consistent with this
opinion.
I.
On the morning of Christmas Eve, Bruce Bunting fell hard
as he exited a CVS store in the District of Columbia. The
surface he slipped on was covered in a mix of salt (or some de-
icing material) and water. Photographs taken shortly after his
fall captured the walkway’s wet condition, and there is no
indication the walkway was icy. As a result of his fall, Bunting
suffered a significant ankle injury.
Bunting and his wife filed suit against District of Columbia
CVS Pharmacy, LLC, in D.C. Superior Court alleging
negligence, negligence per se, and loss of consortium under
D.C. law.1 To support their negligence claim, the Buntings
advanced two primary theories: first, that CVS failed to take
reasonable steps to ensure the walkway was not dangerously
slippery, and second, that CVS failed to warn Bunting of the
hazard. The Buntings also maintained they could establish
negligence per se because CVS’s maintenance of the walkway
1 The Buntings do not dispute their loss of consortium claim is
derivative, requiring dismissal if their negligence claim does not
survive summary judgment.

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violated D.C. municipal safety regulations. CVS timely
removed the case to federal district court.
The Buntings and CVS obtained expert reports to support
their positions. The Buntings’ first report was from Gregory
Harrison, a registered professional civil engineer. Their second
was from Lisa Rose, a certified expert in snow and ice
management. CVS relied primarily on the expert testimony of
Alexandra Maddox, a mechanical and biomedical engineer.
The experts focused on the walkway’s static coefficient of
friction (“COF”)—a standard measure where lower values
indicate a more slippery surface. The parties agreed the
applicable standard of care requires that walkways be
maintained with a COF at or above 0.50.
The expert testimony produced by both parties
demonstrated that the walkway may have had a COF below
0.50 when wet. The Buntings’ expert Harrison indicated the
walkway outside the CVS was dangerously slippery when wet,
with a COF below the 0.50 standard of care. He explained that
“Bunting’s type of fall injury incident simply could not have
happened unless the walkway surface was very slippery and far
below” a COF of 0.50. In his deposition, he emphasized the
case “was just not a close call.” CVS’s expert similarly
produced field notes indicating that a portion of the walkway
near where Bunting fell had a COF of 0.49 when wet.
The district court granted CVS’s motion for summary
judgment. With respect to the negligence claim, the court
reasoned that the Buntings were required to introduce expert
testimony to establish the standard of care. It then held the
Buntings had failed to produce expert testimony creating a
genuine issue of material fact as to whether CVS breached the
0.50 COF standard of care because Harrison had only tested the
walkway with water, rather than with a mix of salt and water.

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The district court explained that the Buntings’ failure to show
that the walkway was unreasonably dangerous defeated their
other negligence theories, including their contention that CVS
breached a duty to warn Bunting of the hazard. Because the
district court concluded this failure independently sustained the
grant of summary judgment on the Buntings’ negligence claim,
it did not reach CVS’s alternative arguments premised on
CVS’s lack of notice of the hazard and the inadmissibility of
the Buntings’ expert testimony under Federal Rule of Evidence
702. The district court also granted summary judgment to CVS
on the negligence per se claim because the relevant municipal
regulations did not impose a duty distinct from the common
law duty of care. The Buntings timely appealed.
II.
We review the district court’s grant of summary judgment
de novo. Holcomb v. Powell, 433 F.3d 889, 895 (D.C. Cir.
2006). Summary judgment is appropriate if there is “no
genuine dispute as to any material fact and the movant is
entitled to judgment as a matter of law.” Fed. R. Civ. P. 56(a).
At summary judgment, “[t]he evidence is to be viewed in the
light most favorable to the nonmoving party and the court must
draw all reasonable inferences in favor of the nonmoving
party.” Talavera v. Shah, 638 F.3d 303, 308 (D.C. Cir. 2011).
We are not “to weigh the evidence and determine the truth of
the matter but to determine whether there is a genuine issue for
trial” to be evaluated by the jury. Anderson v. Liberty Lobby,
Inc., 477 U.S. 242, 249 (1986).
Because this diversity case is governed by D.C. tort law,
we interpret the requirements of D.C. law consistent with
decisions of the D.C. Court of Appeals. Briggs v. Wash. Metro.
Area Transit Auth., 481 F.3d 839, 843 (D.C. Cir. 2007).

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III.
We consider in turn whether summary judgment was
proper with respect to the Buntings’ negligence and negligence
per se claims.
A.
To prevail on a negligence claim under D.C. law, “a
plaintiff must demonstrate that: (1) the defendant owed a duty
of care to the plaintiff, (2) the defendant breached that duty,
and (3) the defendant’s breach proximately caused an injury to
the plaintiff.” KS Condo, LLC v. Fairfax Vill. Condo. VII, 302
A.3d 503, 507 (D.C. 2023). “In the District of Columbia[,] the
applicable standard for determining whether an owner or
occupier of land has exercised the proper level of care to a
person lawfully upon his premises is reasonable care under all
of the circumstances.” Night & Day Mgmt., LLC v. Butler, 101
A.3d 1033, 1038 (D.C. 2014) (cleaned up). The D.C. Court of
Appeals has made clear that “an owner of property has a duty
to exercise reasonable care to cure a dangerous condition if
(1) he has actual or constructive notice of the condition and
(2) he has the right to exercise control over the condition.”
Campbell v. Noble, 962 A.2d 264, 266 (D.C. 2008). Moreover,
property owners have a duty to warn invitees of dangerous
conditions that are “peculiarly foreseeable” to the owner but
not to others. Wash. Metro. Area Transit Auth. v. Barksdale-
Showell, 965 A.2d 16, 24–25 (D.C. 2009).
Under D.C. law, plaintiffs are sometimes required to
establish the standard of care and corresponding breach of that
standard through expert testimony. “In determining whether
expert testimony is required to carry a plaintiff’s burden of
proof, [D.C. courts] ask whether lay jurors would be able to
grasp the issues without expert assistance.” KS Condo, 302
A.3d at 508 (cleaned up). The essential inquiry is “whether the

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issues are beyond an average juror’s grasp or ken.” Id. at 508
n.2. D.C. courts “have previously required expert testimony in
negligence cases which involve issues of safety, security and
crime prevention,” but whether such testimony is required for
the plaintiff to meet the burden of proof always “depends on
the circumstances of the particular case.” Jenkins v. Red Coats,
Inc., 339 A.3d 104, 107 (D.C. 2025) (cleaned up).
The D.C. Court of Appeals has recently emphasized that
“[o]utside the realm of professional malpractice
cases, … causes of action that require expert testimony are
rare.” KS Condo, 302 A.3d at 509 (cleaned up). “[I]n a typical
slip and fall case, lay people serving on a jury often do not
require expert assistance to determine if a warning was
adequate to apprise passersby of the dangerous condition.”
Jenkins, 339 A.3d at 108. In such cases, jurors may employ
their “common knowledge and everyday experience” to
determine whether a proprietor “exercised reasonable care in
warning passersby of the hazard caused by [a] wet floor.” Id.
at 109.
At this stage of the proceedings, the district court erred in
granting summary judgment to CVS on the Buntings’
negligence claim.2
As an initial matter, we agree with the district court that
the Buntings need expert testimony to show the walkway was
2 Our review focuses only on the issues decided by the district court,
recognizing CVS’s alternative arguments have not yet been
addressed. Following the district court, we assume for purposes of
this appeal that all expert testimony provided by Harrison and Rose
is admissible. In subsequent proceedings, the district court must
fulfill its “gatekeeping role” under Federal Rule of Evidence 702 and
assess whether the Buntings have proffered admissible expert
testimony. Daubert v. Merrell Dow Pharms., Inc., 509 U.S. 579, 597

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dangerously slippery. The Buntings’ negligence theories hinge
on whether CVS maintained a dangerously slippery walkway.
Because the Buntings seek to demonstrate the COF fell below
a reasonably safe level when wet, the district court correctly
concluded they have adopted a theory of liability that requires
expert testimony. The coefficient of friction is a matter
“beyond an average juror’s grasp or ken.” KS Condo, 302 A.3d
at 508 n.2; cf. Rosenfeld v. Oceania Cruises, Inc., 654 F.3d
1190, 1194 (11th Cir. 2011) (“[M]atters of slip resistance and
surface friction are beyond the understanding and experience
of the average lay citizen.”) (cleaned up). And the mere
presence of water and salt on an outdoor walkway—a common
sight in winter—does not constitute a “hazard open and
notorious” that can be understood absent expert testimony.
Cosio v. District of Columbia, 940 A.2d 1009, 1010 (D.C.
2008). Nor have the Buntings advanced other evidence or
theories of negligence that might obviate the need for expert
testimony. The expert testimony regarding the dangerousness
of the walkway is essential to the Buntings’ negligence claim.
Nonetheless, the district court erred when it granted
summary judgment to CVS because the expert testimony
created a genuine issue of material fact as to whether the
walkway was dangerously slippery. Both parties agreed that a
COF of 0.50 represents the standard of care, drawing on
national standards such as those from the American National
Standards Institute. Harrison’s testimony indicated that
Bunting’s fall occurred when the walkway’s COF was below
0.50. Moreover, CVS’s expert Maddox produced field notes
(1993). We also do not address whether CVS “ha[d] actual or
constructive notice of the condition,” which the district court must
determine in the first instance. Campbell, 962 A.2d at 266. On
remand, the district court should address CVS’s alternative
arguments and then may again consider whether summary judgment
is warranted.

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indicating that an area near the door where Bunting slipped had
an average COF of 0.49 when wet. D.C. courts have credited
similar testimony as sufficient to create a triable issue of
material fact regarding a surface’s dangerousness in slip and
fall cases. See Reeves v. Wash. Metro. Area Transit Auth., 135
A.3d 807, 809, 812, 813 n.8 (D.C. 2016); Lewis v. Innovative
Facilities Sols., 2018 WL 10561256, at *3 (D.C. Super. Ct. Jan.
11, 2018). On this record, drawing all inferences in favor of the
Buntings, a reasonable jury could conclude that CVS breached
the applicable standard of care by maintaining an unreasonably
dangerous walkway and failing to cure or warn about the
danger.
The district court granted summary judgment to CVS in
part because the experts failed to conduct their testing with a
combination of salt and water. But the inability of any party to
positively identify the salt-like substance that was present does
not preclude a jury trial. We must draw all inferences in the
Buntings’ favor at this stage, and a reasonable jury could
conclude from the evidence that the salt (or salt-like substance)
did not meaningfully mitigate the dangerously slippery surface.
Beyond the testimony showing the walkway was
dangerously slippery, no further expert testimony is required
for jurors to understand issues pertaining to CVS’s duty of care
under the circumstances of this case. The D.C. Court of
Appeals has emphasized that “[i]n the mine-run of cases,
questions of negligence are within the realm of common
knowledge and everyday experience, as they are grounded in
ordinary judgments of reasonableness.” KS Condo, 302 A.3d
at 509 (cleaned up).
Because at this stage of the proceedings a reasonable jury
could conclude the walkway was unreasonably dangerous, it

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was error to grant summary judgment to CVS on the Buntings’
negligence claim.
B.
We next turn to the Buntings’ negligence per se claim. The
district court granted summary judgment on the claim that CVS
committed negligence per se by violating D.C. Municipal
Regulation (“DCMR”) section 2000.5, which provides: “No
person shall occupy with, place, or leave, or cause to be placed
or left on public space, any wet paint or other slippery or sticky
substance, or any deposit dangerous to life and limb, without
protecting and guarding that public space.” 3 24 DCMR
§ 2000.5. The Buntings alleged that by leaving a mix of salt
and water on the walkway and failing to “protect[] and guard[]”
the space, CVS violated the regulation and thus committed
negligence per se.
Under D.C. law, the doctrine of negligence per se permits
a plaintiff to, “in certain circumstances and under specified
conditions, rely on a statute or regulation as proof of the
applicable standard of care.” Butler, 101 A.3d at 1039 (cleaned
up); Ginsberg v. Granados, 963 A.2d 1134, 1140 (D.C. 2009)
(setting out the conditions). To establish negligence per se, “the
statute or regulation ‘must not merely repeat the common law
duty of reasonable care, but must set forth specific guidelines
to govern behavior.’” Butler, 101 A.3d at 1040 (cleaned up).
The district court properly granted summary judgment to
CVS on this claim. Assuming arguendo that the walkway is a
“public space” where the regulation applies, a violation of
section 2000.5 cannot be used to establish negligence per se
3 The Buntings have dropped their argument that CVS’s violation of
12 DCMR § PM-305G.4 also supports their negligence per se claim.

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because it does not impose a duty that differs from the common
law duty of reasonable care. Section 2000.5 requires persons to
“protect[] and guard[]” public spaces if they deposit or place
certain hazards there. At the same time, the D.C. Court of
Appeals has explicitly connected a “duty … to
protect … against … hazards” on a sidewalk with the common
law duty of reasonable care. Bostic v. Henkels & McCoy, Inc.,
748 A.2d 421, 425 (D.C. 2000) (emphasis added); cf. Odemns
v. District of Columbia, 930 A.2d 137, 142 n.8 (D.C. 2007)
(“Landowners have a duty to persons lawfully upon their
premises, after notice of a dangerous condition (actual or
constructive), to exercise reasonable care under the
circumstances to protect them from the danger.”) (emphasis
added). And a person who “occup[ies] with, place[s], or
leave[s], or cause[s] to be placed or left … any deposit
dangerous to life and limb” is axiomatically on notice of the
hazard, so section 2000.5 does not depart from the common
law’s notice requirement.
Since section 2000.5 and the common law duty of care
both concern the protection of other persons from known
hazards, the regulation “merely repeat[s] the common law duty
of reasonable care.” Chadbourne v. Kappaz, 779 A.2d 293, 296
(D.C. 2001) (cleaned up). CVS is entitled to summary
judgment because section 2000.5 cannot be used to establish
negligence per se.
* * *
For the foregoing reasons, we vacate the district court’s
grant of summary judgment in part and remand for further
proceedings consistent with this opinion.
So ordered.

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KAREN LEC RAFT HENDERSON , Circuit Judge, concurring:
I agree with my colleagues that the Buntings must prove their
negligence claim through expert testimony. By stipulating to
the 0.50 Coefficient of Friction (COF) ratio as the benchmark
standard of care, the Buntings injected esoterica into their case
that is beyond the ken of the average juror. See KS Condo, LLC
v. Fairfax Vill. Condo. VII, 302 A.3d 503, 508 (D.C. 2023). I
write separately to highlight that, in my view, it is only by the
slimmest of margins that the deposition testimony of the
Buntings’ “expert,” Gregory Harrison, created a genuine
dispute as to whether the COF of CVS’s walkway was below
0.50 on the day of Bunting’s fall.
Harrison testified that he tested the COF of the walkway
with just “a water bottle and a shoe.” J.A. 101. For the
uninitiated, experts in slip-and-fall cases typically use a fine-
tuned device called a Variable Incidence Tribometer to test a
surface’s COF because it is calibrated to yield precise
measurements. See, e.g., Piazza v. Target Corp., No. 21-835,
2022 WL 16923867, at *1 (M.D. Fla. Nov. 14, 2022); see also
Frazza v. United States, 529 F. Supp. 2d 61, 72 (D.D.C. 2008).
Harrison pooh-poohed that “so-called scientific” method as
inferior to his approach, J.A. 101, because after years of
“training and experience” he had conditioned himself to
become “calibrated, literally, mentally calibrated,” J.A. 100, to
judge a surface’s COF based on nothing more than its
“subjective feel,” J.A. 101. After splashing a bit of water on
the surface where Bunting fell and sliding his foot across it,
Harrison deduced that it was “very slippery when wet” and “far
below” a COF of 0.50—although he did not give any precise
measurement. J.A. 112. When asked whether his method was
a scientifically acceptable one, Harrison demurred, “Well, [a]
judge upheld it and I’ve survived . . . all the Daubert challenges
over 35 years,” a feat he later conceded was “an incredible
stroke of luck.” J.A. 101. Nor did it much matter to Harrison
that he had tested CVS’s walkway using only water even
though Bunting testified at his deposition that it was a granular

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“slurry mixture” of salt and water that caused his fall. J.A. 77.
Harrison didn’t “really . . . care” about replicating those
conditions in his testing—or at least trying to—because, in his
view, “it’s all the same, it’s water.” J.A. 95, 96.
Assuming Harrison’s testimony was even admissible as
expert evidence, I hesitate in agreeing with my colleagues that
it created a genuine dispute as to CVS’s breach of the standard
of care. Harrison’s core finding—that CVS’s walkway was
“very slippery” and “far below” the standard of care when wet
with water—bordered on ipse dixit. See J.A. 99 (“Q. I presume
you don’t come up with numbers when you do this kind of a
test[?] A. It’s . . . subjective based on education and training.”).
And his view that “it’s all the same, it’s water” hardly proved
that testing the COF of CVS’s walkway under the alleged
“slurry” conditions would have been unnecessary. Ultimately,
however, these are issues that the district court can address
when deciding whether Harrison “is qualified as an expert” to
offer his opinions in this case. Fed. R. Evid. 702. With that
caveat, I join the opinion in full.

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