Moore v. British Airways PLC

United States Court of Appeals
For the First Circuit

No. 21-1037

JENNIFER MOORE,

Plaintiff, Appellant,

v.

BRITISH AIRWAYS PLC, a foreign corporation,

Defendant, Appellee.

APPEAL FROM THE UNITED STATES DISTRICT COURT
FOR THE DISTRICT OF MASSACHUSETTS

[Hon. Mark G. Mastroianni, U.S. District Judge]

Before

Kayatta, Selya, and Howard,
Circuit Judges.

Kevin Chrisanthopoulos for appellant.
Marissa N. Lefland, with whom Anthony U. Battista, Samantha
M. Holloway, and Condon & Forsyth LLP were on brief, for appellee.

April 29, 2022
 SELYA, Circuit Judge. We have noted before that "words

are like chameleons; they frequently have different shades of

meaning depending upon the circumstances." United States v.

Romain, 393 F.3d 63, 74 (1st Cir. 2004). This appeal turns on

just such an exercise in exegesis — the meaning of the word

"accident," as that word is used in Article 17(1) of the Montreal

Convention, formally known as the Convention for the Unification

of Certain Rules for International Carriage by Air, May 28, 1999,

S. Treaty Doc. No. 106-45 (2000), 2242 U.N.T.S. 350.

This case has its genesis in an airline passenger's fall

while disembarking from an aircraft by means of a mobile staircase,

the last step of which was appreciably more precipitous than the

earlier ones. The principal question on appeal is whether the use

of such a staircase, under the circumstances, was an event that

may constitute an "accident" within the meaning of the Montreal

Convention. Concluding, as we do, that a jury could supportably

find that the event was unexpected and that the passenger's

injuries resulted from such an accident, we vacate the district

court's entry of summary judgment for the airline, affirm its

denial of the passenger's motion for partial summary judgment, and

remand for further proceedings.

I

We briefly rehearse the relevant facts (which are

largely undisputed) and the travel of the case. On September 14,

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2018, the plaintiff, Jennifer Moore, flew from Boston to London

aboard a Boeing 777 airliner operated by the defendant, British

Airways PLC. The red-eye flight touched down at London's Heathrow

Airport at around 9:00 a.m. on September 15. While taxiing to the

gate, the flight crew learned that the jet bridge ordinarily used

to disembark passengers was inoperable. Consequently, deplaning

passengers would need to use a mobile staircase (an apparatus

commonly used at Heathrow and other airports of comparable scale

and scope).

After the aircraft was parked at the gate, the ground

crew secured the mobile staircase against the fuselage. The

passengers — including the plaintiff and her travel companion,

Tammy Burnett — then began to disembark. By all accounts, the

disembarkation process was calm and orderly. The passengers

proceeded down the staircase in single file without any noticeable

jostling or other untoward behavior. The stairs were clean — free

of debris and other foreign substances — and the weather was clear.

Ms. Burnett preceded the plaintiff down the mobile

staircase. As Ms. Burnett testified in her deposition, she "was

surprised at the last step being a little further than a normal

cadence of a staircase" and, thus, "the bottom step didn't arrive

when I thought it would." She nonetheless kept her balance and

then "turned around to tell [the plaintiff] to watch her step,"

only to discover that the plaintiff had taken a tumble. In

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describing her fall, the plaintiff testified that when she reached

the last step "it was further down than I was expecting," which

"thr[ew] off my balance and both of my ankles turned and I went

down."

There were no British Airways employees at the bottom of

the stairs and no one warned the passengers about the height of

the final step. After the plaintiff fell — and in accordance with

British Airways' internal policy — the mobile staircase was taken

out of service and inspected for defects. The inspection confirmed

that the stairs were in their normal operating condition, free of

defects and working as intended at the time of the incident. The

inspection also confirmed that the distance from the bottom step

to the ground was "noticeably slightly different" than the distance

between the steps themselves.

The plaintiff's expert, Chad Phillips, prepared a report

estimating from photographs that the riser height of each step on

the mobile staircase was 7.4 inches, whereas the riser height of

the bottom step (the distance between that step and the ground)

was 13 inches. In his opinion, "this excessive riser [height]

difference exposed [the plaintiff] to a misstep hazard and caused

her to take an air step resulting in her injuries." An "air step,"

he explained, occurs by stepping "onto an unexpected depression or

step down."

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 Phillips further opined that the mobile staircase was

used in a manner that did not conform to industry standards. In

this regard, he referred to British Standard 5395-1:2000, which

states that "[t]he maximum rise that people can be expected to

negotiate safely is 220mm," or 8.7 inches. He also referred to

European Standard EN 12312-1:2001+A1:2009, entitled "Aircraft

Ground Support Equipment - Specific Requirements - Part 1:

Passenger Stairs," which provides that "[a]ll steps of a stair

flight shall be designed with the same riser height" and that the

distance from the ground to the tread surface of the bottom step

"shall not exceed 260mm," or 10.24 inches.

The plaintiff sustained severe injuries as a result of

her fall. Accordingly, she sued British Airways under the Montreal

Convention for damages in an unspecified amount (her complaint

contained no specific ad damnum, but sought recovery "in excess of

the jurisdictional limits of [the district court]"). She alleged,

in substance, that the injuries sustained in her fall resulted

from an accident within the meaning of Article 17(1) of the

Montreal Convention.1

1 Her complaint also contained a common law claim for
negligence. The district court dismissed this claim as preempted
by the Montreal Convention, see Moore v. British Airways PLC, 511
F. Supp. 3d 1, 6 (D. Mass. 2020), and the plaintiff has not appealed
that ruling. Thus, we make no further mention of this claim.

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 After pretrial discovery had run its course, British

Airways moved for summary judgment. See Fed. R. Civ. P. 56(a).

It argued that, as a matter of law, the plaintiff's injuries did

not result from an accident within the meaning of the Montreal

Convention. The plaintiff opposed the motion and cross-moved for

partial summary judgment on the issue of whether her injuries

stemmed from such an accident. Following a hearing, the district

court granted British Airways' motion for summary judgment and

denied the plaintiff's cross-motion. See Moore v. British Airways

PLC, 511 F. Supp. 3d 1, 2-3, 7 (D. Mass. 2020). In so ruling, the

court determined that the plaintiff's injuries were not the result

of an accident within the meaning of the Montreal Convention. See

id. at 6-7. This timely appeal ensued.

II

It is by now apodictic that orders granting summary

judgment engender de novo review. See Finamore v. Miglionico, 15

F.4th 52, 58 (1st Cir. 2021). In conducting this tamisage, we

assess "the record and all reasonable inferences therefrom in the

light most hospitable to the summary judgment loser" (here, the

plaintiff). Houlton Citizens' Coal. v. Town of Houlton, 175 F.3d

178, 184 (1st Cir. 1999). Summary judgment is appropriate only

when the record, so viewed, "reflects no genuine issue as to any

material fact" and the movant demonstrates an entitlement to

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judgment as a matter of law. Morelli v. Webster, 552 F.3d 12, 18

(1st Cir. 2009); see Fed. R. Civ. P. 56(a).

If the nonmovant bears the ultimate burden of proof on

a given issue, "she cannot rely on an absence of competent

evidence" alone to show that the issue is trialworthy. McCarthy

v. Nw. Airlines, Inc., 56 F.3d 313, 315 (1st Cir. 1995). Instead,

she "must present definite, competent evidence sufficient to

establish the elements of [her] claim in order to survive a motion

for summary judgment." Alston v. Int'l Ass'n of Firefighters,

Local 950, 998 F.3d 11, 24 (1st Cir. 2021) (internal quotation

omitted) (quoting Pina v. Children's Place, 740 F.3d 785, 795-96

(1st Cir. 2014)).

A

The Montreal Convention is a multilateral treaty

governing the liability of air carriers for certain injuries and

damages that occur during international air carriage. See Dagi v.

Delta Airlines, Inc., 961 F.3d 22, 27 (1st Cir. 2020). The United

States and the United Kingdom are among the signatories to the

Convention. See id.

The Montreal Convention establishes a two-tiered

liability regime for passenger injuries caused by an accident.

The carrier is strictly liable for damages up to 128,821 Special

Drawing Rights, an amount determined by the International Monetary

Fund that is approximately $175,000. See Montreal Convention,

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arts. 21(1), 23; Inflation Adjustments to Liability Limits

Governed by the Montreal Convention Effective December 28, 2019,

85 Fed. Reg. 3104, 3105 (Jan. 17, 2020); International Monetary

Fund, SDR Valuation, https://www.imf.org/external/np/fin/data/rm

s_sdrv.aspx (last visited April 28, 2022). For damages over that

ceiling, a carrier can avoid liability if it can prove that "such

damage was not due to the negligence or other wrongful act or

omission of the carrier" or that "such damage was solely due to

the negligence or other wrongful act or omission of a third party."

Montreal Convention, art. 21(2). What is more, the carrier may

reduce or eliminate its liability for all damages to the extent it

"proves that the damage was caused or contributed to by the

negligence or other wrongful act or omission of the person claiming

compensation." Id., art. 20.

The Montreal Convention has preemptive force with

respect to passenger injuries suffered either on board an aircraft

or during embarkation or disembarkation. Recovery for such a

claim, "if not allowed under the Convention, is not available at

all" under a nation's local laws. El Al Israel Airlines, Ltd. v.

Tseng, 525 U.S. 155, 161 (1999) (interpreting Warsaw Convention);

see Dagi, 961 F.3d at 24, 27-28 (same for Montreal Convention).

The case at hand turns on Article 17(1) of the

Convention, which provides in full: "The carrier is liable for

damage sustained in case of death or bodily injury of a passenger

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upon condition only that the accident which caused the death or

injury took place on board the aircraft or in the course of any of

the operations of embarking or disembarking." To recover under

this provision, the plaintiff must show that an "accident"

occurred, which proximately caused a passenger's death or injury

(either physical or having a physical manifestation) and which

took place either on board the aircraft or while embarking or

disembarking. See Acevedo-Reinoso v. Iberia Líneas Aéreas de

España S.A., 449 F.3d 7, 12 (1st Cir. 2006).2 The plaintiff is

not required to show that her injuries resulted from any negligence

on the air carrier's part.

Here, only the first element of the required showing —

the existence of an "accident" — is at issue. The Montreal

Convention does not define the word "accident," but it is used in

Article 17(1) as a term of art. In deciphering its meaning, the

primary decryption tool available to us is the Supreme Court's

opinion in Air France v. Saks, 470 U.S. 392 (1985). There, the

Although Acevedo-Reinoso and the case law on which it relied
2

interpreted the Warsaw Convention of 1929 — which has now been
superseded by the Montreal Convention — we have explained that a
court may "rely on case law arising from the Warsaw Convention in
interpreting the Montreal Convention when the provisions of the
two Conventions are essentially the same." Dagi, 961 F.3d at 27
n.4. Because Article 17(1) of the Montreal Convention is
essentially the same as its Warsaw Convention counterpart, see id.
at 27-28 (relying on case law interpreting Article 17 of the Warsaw
Convention in construing Article 17(1) of the Montreal
Convention), we treat relevant Warsaw Convention case law as
authoritative here.

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Court defined an "accident," for purposes of Article 17 of the

Warsaw Convention (the predecessor of the Montreal Convention), as

"an unexpected or unusual event or happening that is external to

the passenger." Id. at 405. Conversely, an injury that "results

from the passenger's own internal reaction to the usual, normal,

and expected operation of the aircraft" is not "caused by an

accident" within the meaning of the Warsaw Convention. Id. at

406. Mindful of the ambiguities lurking in this formulation, the

Saks Court appended two practical directions. First, it stressed

that "[t]his definition should be flexibly applied after

assessment of all the circumstances surrounding a passenger's

injuries." Id. at 405. Second, it cautioned that "where there is

contradictory evidence, it is for the trier of fact to decide

whether an 'accident' as here defined caused the passenger's

injury." Id.3

In Dagi, the occurrence of an "accident" was not disputed.
3

See 961 F.3d at 28. Nevertheless, we said that "[t]o allege an
'accident,' the claim must allege an occurrence which 'arises from
some inappropriate or unintended happenstance in the operation of
the aircraft or airline.'" Id. (quoting Fishman v. Delta Air
Lines, Inc., 132 F.3d 138, 143 (2d Cir. 1998)). The court below
read this dictum as if it imposed an "additional[]" test beyond
the Saks formulation. Moore, 511 F. Supp. 3d at 5-6 & n.3. We
reject this reading and disavow any intention of altering the Saks
formulation. Dagi is best read as furnishing examples of
occurrences that come within the Saks formulation. The same is
true of Fishman, 132 F.3d at 143 (quoted in Dagi).

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 B

The plaintiff posits that her injuries were caused by an

accident because it was unexpected that she would have to disembark

from the aircraft on a mobile staircase in which the bottom step

was 13 inches from the ground, even though the first twenty-odd

steps each had a riser height of 7.4 inches and no warning was

given about the bottom step's greater height.4 There is no dispute

that deploying such a staircase was an event that was external to

the passenger, as required by Saks. The parties' only quarrel,

therefore, is whether disembarking on a staircase constructed in

this way should be considered "unexpected or unusual" under the

circumstances.

The district court granted British Airways' motion for

summary judgment because the plaintiff offered no "evidence that

the height of the last step was unusual for mobile staircases" or

that this design was "atypical from other mobile staircases used

to disembark passengers." Moore, 511 F. Supp. 3d at 6-7. At oral

argument in this court, the plaintiff's counsel agreed that no

such evidence has been identified. Consequently, summary judgment

would be appropriate if the inquiry stopped there. But it does

not.

The plaintiff does not argue that the event constituting
4

the "accident" was either the fall itself or the jet bridge's
malfunction. Accordingly, we deem any such arguments waived. See
United States v. Zannino, 895 F.2d 1, 17 (1st Cir. 1990).

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 The Saks formulation simply does not confine the inquiry

to whether the event was unusual; it also requires the court to

ask whether the event was unexpected. Words often shadow-dance

with each other, and "unusual" and "unexpected" are, admittedly,

somewhat overlapping categories. But only somewhat. For example,

a solar eclipse is likely to be an unusual event — but if it is

widely forecast by astronomers across the globe, it is likely to

be expected.

Giving the constituent terms of the Saks formulation

their "ordinary" meanings, Olympic Airways v. Husain, 540 U.S.

644, 655 (2004), we cannot say that these categories are entirely

congruent. The ordinary meaning of "unexpected" is "[c]oming

without warning; unforeseen." American Heritage Dictionary 1950

(3d ed. 1992). The Supreme Court has accentuated this established

meaning of unexpected by glossing the Saks definition of accident

as "an unforeseen event." Zicherman v. Korean Air Lines Co., 516

U.S. 217, 223 (1996). In contrast, "unusual" means "[n]ot usual,

common, or ordinary." American Heritage Dictionary, supra, at

1960. There is obvious daylight between the definitions of these

two terms.

The court below failed to analyze whether the event that

caused the plaintiff's injuries was unexpected or, synonymously,

unforeseen. Exercising de novo review, see Finamore, 15 F.4th at

58, we turn to that question.

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 In mounting this inquiry, the problem of perspective

looms large: what is or is not expected often lies in the eye of

the beholder. An occurrence long foreseen by one person may

blindside another. Or — framed in the context of the Montreal

Convention — what an airline expects to happen in the course of a

flight may not perfectly match a passenger's expectations. The

Saks formulation tells us that an unexpected event, external to

the passenger, is an accident — but it says nothing about the

relevant coign of vantage, leaving open the question: "unexpected

by whom?"

The parties suggest different ways in which to fill this

void. The plaintiff submits that the appropriate lens through

which to ascertain whether a given event is expected belongs to

the hypothetical "average traveler." British Airways, in

contrast, submits that the proper perspective is that of the

airline industry. According to British Airways, the height

difference of the staircase's bottom step cannot be a ground for

finding the existence of an "accident" under Article 17(1) for the

simple reason that such a difference is "normal and routine" across

the industry.

We conclude that whether an event is unexpected under

the Saks definition of "accident" should be judged from the

perspective of a reasonable passenger with ordinary experience in

commercial air travel. This conclusion derives from three sources:

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the text of the Montreal Convention, its elucidation by both

American and foreign courts, and its objects and purposes. We

explain briefly.

1

The Montreal Convention is a treaty. "The

interpretation of a treaty, like the interpretation of a statute,

begins with its text." Medellin v. Texas, 552 U.S. 491, 506

(2008). The Supreme Court has made pellucid that the word

"accident," as used in Article 17 of the Warsaw Convention — the

lineal ancestor of Article 17 of the Montreal Convention — is broad

enough to encompass intentional acts. See Olympic Airways, 540

U.S. at 651 & n.7. When used in that sense, referring to an event

"happening wholly or partly through human agency," an accident is

"an event which under the circumstances is unusual and unexpected

by the person to whom it happens." Id. at 651 n.6 (quoting Black's

Law Dictionary 15 (6th ed. 1990) (emphasis supplied)). This

definition recognizes that even an intentional act may be an

accident from the point of view of a victim who did not anticipate

its occurrence. In much the same vein, the plain meaning of the

word "accident" in Article 17(1) of the Montreal Convention

suggests a focus on the perspective of the passenger, not the

airline.

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 2

In interpreting Article 17 of the Warsaw Convention, the

Saks Court relied in part on "the weight of precedent in foreign

and American courts." 470 U.S. at 400. We too do so.5 The trend

of this jurisprudence runs in favor of assessing whether an event

is unexpected from the standpoint of an ordinary, reasonable

passenger in the plaintiff's position.

In the lead opinion for the House of Lords in Deep Vein

Thrombosis and Air Travel Group Litigation — a Warsaw Convention

case — Lord Scott wrote that courts must examine whether the event

was "'unintended and unexpected' from the viewpoint of the victim

of the accident" because "[i]t is the injured passenger who must

suffer the 'accident' and it is from his perspective that the

quality of the happening must be considered." [2005] UKHL 72,

5 Although reliance on the opinions of foreign tribunals may
be controversial in other settings, see, e.g., Roper v. Simmons,
543 U.S. 551, 622-28 (2005) (Scalia, J., dissenting) (rejecting
resort to "the views of foreigners" and "alien law" when
interpreting American law); Foster v. Florida, 537 U.S. 990, 990
n.* (2002) (Thomas, J., concurring) ("[T]his Court's Eighth
Amendment jurisprudence should not impose foreign moods, fads, or
fashions on Americans."), it is common ground that such opinions
are instructive in interpreting treaties, see, e.g., GE Energy
Power Conversion France SAS, Corp. v. Outokumpu Stainless USA,
LLC, 140 S. Ct. 1637, 1646 (2020); Olympic Airways, 540 U.S. at
660 (Scalia, J., dissenting) ("We can, and should, look to
decisions of other signatories when we interpret treaty
provisions."). Thus, the Saks Court concluded that "[i]n
determining precisely what causes can be considered accidents, we
find the opinions of our sister signatories to be entitled to
considerable weight." 470 U.S. at 404 (internal quotation
omitted).

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[2006] 1 AC (HL) 495, 504, ¶ 14 (appeal taken from Eng.). American

courts have expressed similar views. See, e.g., Campbell v. Air

Jamaica Ltd., 760 F.3d 1165, 1173 (11th Cir. 2014) (stating that

the "Article 17 analysis . . . measures only whether the event was

unusual from the viewpoint of the passenger, not the carrier").

We hasten to add a cautionary note. Lord Scott's opinion

— if read literally — could be taken as privileging the passenger's

subjective expectations, no matter how idiosyncratic. Such a

reading, however, has been roundly rejected. By and large, courts

have been unwilling to adopt a subjective test. See Gotz v. Delta

Airlines, Inc., 12 F. Supp. 2d 199, 202 (D. Mass. 1998) (stating

that Saks requires an objective inquiry and "plaintiff's

subjective expectations" do not control); see also Craig v.

Compagnie Nationale Air France, 45 F.3d 435, 1994 WL 711916, at *3

(9th Cir. 1994) (unpublished table decision) (holding that

plaintiff's "belief is not controlling" with respect to whether

event was expected); Tseng v. El Al Israel Airlines, Ltd., 122

F.3d 99, 103 (2d Cir. 1997) (same), rev'd on other grounds, 525

U.S. 155 (1999). Thus, the court below reasoned — and neither

party disputes — that the relevant inquiry is "an objective one,

not a subjective inquiry based on the plaintiff's personal

expectations." Moore, 511 F. Supp. 3d at 5.

The Court of Justice for the European Union (CJEU) also

has rejected any reading of "accident" that is "based on the

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perspective of each passenger." Case C-70/20, YL v. Altenrhein

Luftfahrt GmbH, ECLI:EU:C:2021:379, ¶ 35 (May 12, 2021).6 The

court explained that a subjective "interpretation could lead to a

paradoxical result if the same event were classified as

'unforeseen' and, therefore, as an 'accident' for certain

passengers, but not for others." Id. Moreover, a purely

subjective approach "could extend [the concept of 'accident'] in

an unreasonable manner to the detriment of air carriers." Id. ¶

36. The CJEU found this second consideration especially

significant given the Montreal Convention's preamble, which

declares that an object of the treaty is "[achieving an] equitable

balance of interests." Id. (quoting Montreal Convention, pmbl.).

We agree with these courts, domestic and foreign, that

an individual passenger's subjective beliefs do not inform the

question of whether an event is unexpected and, thus, may be found

to be an accident. The appropriate inquiry is an objective one.

In conducting that inquiry, there is no principled basis

for giving primacy to the perspective of either the air carrier or

the airline industry as a whole. Few, if any, cases take such an

6We note that — unlike the courts of many jurisdictions —
the CJEU has adopted a definition of "accident" under Article 17(1)
that differs somewhat from the Saks definition: "an unforeseen,
harmful and involuntary event." YL, ECLI:EU:C:2021:379, ¶ 20
(internal quotation omitted). This case does not require us to
explore the effect, if any, of the discrepancy between this
definition and the Saks definition.

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approach.7 Instead, courts typically toe the line drawn by the

Supreme Court of Victoria (Australia), which indicates that "what

is . . . 'unexpected' . . . should be ascertained from the

viewpoint of an ordinary, reasonable passenger." Qantas Ltd. v.

Povey, [2003] VSCA 227, ¶ 22, 2003 WL 23000692 (Dec. 23, 2003)

(Ormiston, J.A.), aff'd, [2005] HCA 33.

Many other courts have elected to analyze whether an

event is expected through the prism of an "ordinary" or

"reasonable" passenger. E.g., Garcia Ramos v. Transmeridian

Airlines, Inc., 385 F. Supp. 2d 137, 141 (D.P.R. 2005) ("[A]

reasonable passenger would not expect a fellow passenger to fall

on top of him."); Maxwell v. Aer Lingus Ltd., 122 F. Supp. 2d 210,

211 (D. Mass. 2000) ("While a reasonable passenger would expect

some shifting of the contents of an overhead bin, . . . she would

not expect . . . to be struck on the head by a falling object when

the bin above her seat is opened by a fellow passenger."); Fulop

v. Malev Hungarian Airlines, 175 F. Supp. 2d 651, 665 (S.D.N.Y.

2001) (inquiring into what "the ordinary traveler reasonably would

7 One outlier may be Blansett v. Continental Airlines, Inc.,
in which the Fifth Circuit held that failure to warn of the risk
of developing deep vein thrombosis syndrome could not be an
accident under Article 17 because the airline's "policy [of not
requiring such warnings] was far from unique" among international
carriers at the time "and was fully in accord with the expectations
of the [Federal Aviation Administration]." 379 F.3d 177, 182 (5th
Cir. 2004). To the extent — if at all — that Blansett spurns a
passenger-focused perspective as to whether an event is
unexpected, we reject its reasoning.

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expect"). In a case involving an allegedly traumatizing security

inspection at an airport, for example, the Second Circuit held

that "[w]hether [the passenger] expected to be subjected to a

security search is not a relevant consideration because she

reasonably should have been aware that she might be." Tseng, 122

F.3d at 103. We follow this trend and hold that the inquiry into

whether an event is "expected" should be conducted from the

perspective of the ordinary, reasonable passenger.

3

An inquiring court should, when possible, construe the

terms of a treaty in light of the treaty's "objects and purposes."

Monasky v. Taglieri, 140 S. Ct. 719, 728 (2020) (quoting Abbott v.

Abbott, 560 U.S. 1, 20 (2010)); see Eastern Airlines, Inc. v.

Floyd, 499 U.S. 530, 546 (1991) (reading Article 17 of the Warsaw

Convention in line with the treaty's "purpose"); Vienna Convention

on the Law of Treaties, opened for signature May 23, 1969, 1155

U.N.T.S. 331, art. 31(1) ("A treaty shall be interpreted in good

faith in accordance with the ordinary meaning to be given to the

terms of the treaty in their context and in the light of its object

and purpose."). The "primary purpose" of the Warsaw Convention

was "limiting the liability of air carriers in order to foster the

growth of the fledgling commercial aviation industry." Floyd, 499

U.S. at 546. As commercial air travel matured, the Warsaw

Convention's solicitude toward airlines at the expense of

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travelers became problematic. A course correction was due and, in

1999, the Montreal Convention was drafted to supplant the Warsaw

Convention. In 2003, the Montreal Convention was ratified by the

United States and entered into force internationally. See Ehrlich

v. Am. Airlines, Inc., 360 F.3d 366, 371 n.4, 372 (2d Cir. 2004).

The Montreal Convention does not mince words: it

declares its purpose, in part, as "ensuring protection of the

interests of consumers in international carriage by air" and

recognizes "the need for equitable compensation based on the

principle of restitution." Montreal Convention, pmbl. Scholars

aptly "have described the Montreal Convention as a treaty that

favors passengers rather than airlines," Ehrlich, 360 F.3d at 371

n.4, and have read its preamble as "acknowledging the previous

imbalance of interests and staking out where the priority lies,"

Bin Cheng, A New Era in the Law of International Carriage by Air:

From Warsaw (1929) to Montreal (1999), 53 Int'l & Compar. L.Q.

833, 844 (2004). Even so, the Montreal Convention is not one-

sided. The driving forces behind it explicitly strive to attain

"an equitable balance of interests." Montreal Convention, pmbl.;

see George N. Tompkins, Jr., Liability Rules Applicable to

International Air Transportation as Developed by the Courts in the

United States 34 (2010) (concluding that the Montreal Convention

"approach is a shift away from the approach of the 1929 Warsaw

Convention, which primarily favored airlines, to a treaty which

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shows increased concern for and recognition of the rights of

passengers . . ., while still protecting airlines from crippling

liability"). When all is said and done, however, the rights and

interests of passengers cannot lightly be brushed aside. Given

the Convention's intent to strike an equitable balance that better

protects consumers, it would be incongruous if recovery were

impossible for injuries suffered due to events that an ordinary,

reasonable passenger would not expect to happen.

We add, moreover, that fixing the inquiry on the

passenger's objectively reasonable expectations is consistent with

the specific purpose of holding air carriers liable (to a point)

for injuries caused by accidents, whether or not they acted

negligently. As a matter of efficient "'distribution of risk, the

carrier would seem, in nearly every case, to be in the best

position to . . . spread the risk most economically' regardless of

fault." Wallace v. Korean Air, 214 F.3d 293, 297 (2d Cir. 2000)

(omission in original) (quoting Andreas F. Lowenfeld & Allan I.

Mendelsohn, The United States and The Warsaw Convention, 80 Harv.

L. Rev. 497, 599-600 (1967)); see Magan v. Lufthansa German

Airlines, 339 F.3d 158, 162 n.3 (2nd Cir. 2003). In light of this

consideration, it would be perverse to force injured plaintiffs to

bear the cost of accidents unforeseeable to reasonable passengers

with ordinary experience in commercial air travel, especially when

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such incidents are within the reasonable anticipation of airlines

and thus more easily built into their actuarial calculus.

4

The short of it is that the Montreal Convention's text,

its construction by the majority of domestic and foreign courts,

and its objects and purposes all converge on the conclusion that

a passenger's objectively reasonable expectations should control.

We hold, therefore, that under the Saks definition of "accident"

applicable to Article 17(1) of the Montreal Convention, an event

is unexpected when a reasonable passenger with ordinary experience

in commercial air travel, standing in the plaintiff's shoes, would

not expect that event to happen.8

C

What remains is for us to apply the discerned standard

to the facts of the case at hand. We do so "flexibly" and "after

assessment of all the circumstances surrounding a passenger's

injuries." Saks, 470 U.S. at 405. If the evidence is conflicting,

"it is for the trier of fact to decide whether an

'accident' . . . caused the passenger's injury." Id. We conclude

We need not — and do not — decide today whether a passenger's
8

subjective expectations might be relevant under Article 17(1) in
the case of a passenger with exceptional experience in and
knowledge about commercial air travel, such that she actually
foresaw an event that would have been unexpected by an ordinary
passenger. By the same token, we do not decide whether or how the
objective inquiry should take account of passengers with special
cognitive facilities (such as children).

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that the record presents sufficient evidence for a reasonable jury

to find that the plaintiff's injuries were caused by an "accident"

within the meaning of Article 17(1).

The combined force of four facts supports (but does not

compel) the inference that an ordinary, reasonable passenger in

the plaintiff's position would not have expected to disembark on

a staircase in which the bottom step had such a yawning riser

height. First, all of the steps on the staircase before the bottom

step were of a uniform height — a height several inches less than

that of the bottom step. The plaintiff's expert asserted that

someone descending a staircase "tend[s] to develop a specific gait

and expectation that the stairs are uniform." That "expectation"

evolves into a "stepping pattern" as the staircase progresses and

"an unexpected difference in stair dimensions" can interrupt the

pattern, causing a fall. Relatedly, the expert opined that the

plaintiff fell because she took an "air step," which he described

as occurring due to "an unexpected depression or step down." A

jury could find this analysis convincing.

Second, the plaintiff's travel companion, Ms. Burnett,

testified that she was "surprised" because "the bottom step didn't

arrive when [she] thought it would." A jury could appropriately

take Ms. Burnett as a proxy for the ordinary passenger, whose

expectations were, under the circumstances, objectively

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reasonable. And such a jury could credit her testimony that the

height of the bottom step was unexpected.

Third, a jury could find that the passengers were not

warned of the bottom step's elevated riser height. On this point,

British Airways does not deny the absence of any specific warnings

but insists that it was under no obligation to give any such

warnings. Even assuming (without deciding) that no such obligation

existed, the absence of an obligation does not take British Airways

very far. Cf. Phifer v. Icelandair, 652 F.3d 1222, 1224 (9th Cir.

2011) ("Although [Federal Aviation Administration] requirements

may be relevant to the . . . 'accident' analysis, they are not

dispositive of it."). The issue is not whether British Airways

deviated from the appropriate standard of care but, rather, whether

an ordinary, reasonable passenger disembarking from the aircraft

would have expected to traverse a staircase in which the bottom

step had a riser height significantly greater than the earlier

steps. A jury could find that the absence of any warning calling

attention to that height differential was relevant to a passenger's

expectations of what lay ahead.

Fourth, the standards cited by the plaintiff's expert

could supply a reasonable jury with grounds for an inference that

using such a staircase was unexpected. Those standards variously

state that "[t]he maximum rise that people can be expected to

negotiate safely is 220mm," or 8.7 inches; that "[a]ll steps of a

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stair flight shall be designed with the same riser height"; and

that the distance from the ground to the tread surface of the

bottom step "shall not exceed 260mm," or 10.24 inches.

British Airways contends, and the district court agreed,

that these standards are irrelevant because they are "voluntary."

Moore, 511 F. Supp. 3d at 6. But even voluntary standards may be

evidence of what an ordinary, reasonable passenger might expect to

encounter.

British Airways also contends that these standards are

not probative because they do not apply to mobile staircases of

the kind at issue here. This contention lands closer to the mark,

but it cannot settle the matter on summary judgment. At the

summary judgment stage, the facts must be taken in the light most

congenial to the plaintiff. See Houlton Citizens' Coal., 175 F.3d

at 184.

Whether the standards relied on by the plaintiff's

expert provide guidance for mobile staircases is, at a minimum, a

disputed question of fact. Although British Standard 5395-1:2000,

by its terms, "does not apply to steps or stairs which are not

connected to a building," the expert explained in his deposition

that the section of that standard referring to "the negotiation of

stairs" higher than 8.7 inches applies equally to all types of

stairs. Specifically, the expert stated that "I don't believe

there's any difference between negotiating stairs that are on

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wheels or negotiating stairs attached to a building." A jury,

accepting this expert opinion, could reasonably find the disputed

standard applicable here. And in all events, the other standard,

"Aircraft Ground Support Equipment - Specific Requirements - Part

1: Passenger Stairs," appears to apply squarely to the type of

stairs involved in this incident.

Of course, the evidence is not exclusively on the

plaintiff's side. For instance, it is undisputed that mobile

staircases of the kind employed here are commonly used in the

airline industry. The flight crew's first officer described the

use of such mobile staircases to disembark passengers from an

aircraft, without contradiction, as "incredibly normal" and "very

frequent." Similarly, the director of the cabin crew described

the use of such mobile staircases — again, without contradiction

— as "quite an acceptable way to disembark the aircraft." Even

the plaintiff acknowledged that she had seen mobile staircases

used at airports in the past and that she herself had used such a

staircase to board a flight on at least one occasion (though never

to disembark).

From these and other pieces of evidence, a jury may be

persuaded that an ordinary, reasonable passenger would share the

perceptions of the flight crew and, accordingly, that nothing about

the use of this staircase could be said to be unexpected. Saks

teaches, though, that "where there is contradictory evidence, it

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is for the trier of fact to decide whether an 'accident' as

[defined in Saks] caused the passenger's injury." Saks, 470 U.S.

at 405. This is such a case. See Sensat v. Sw. Airlines Co., 363

F. Supp. 3d 815, 823 (E.D. Mich. 2019) (holding that "the gap in

an airstairs tread reasonably could be found to

be . . . 'unexpected' to a passenger who was not warned of its

presence and had no reason to anticipate or spot the hazard");

Garrett v. Emirates, No. 14-02717, 2018 WL 1316976, at *1, 8 (E.D.

Cal. Mar. 14, 2018) (finding trialworthy question of fact as to

whether "accident" occurred where, in part, mobile staircase

"contained a landing partway down that was approximately twice the

size of the stairs and the landing did not contain any warnings to

differentiate it from the other stairs" and airline did not "warn

passengers they would be deplaning via a non-uniform stairway that

contained a landing"); Singhal v. British Airways Plc, [2007] 10

WLUK 552, ¶¶ 4, 38, 2008 WL 4820370 (Oct. 11, 2007) (Wandsworth

County Ct.) (Eng.) (finding "accident" where plaintiff fell due to

"unexpected and unforeseen six inch step" from aircraft door to

jetway and no warnings of this change in level were provided).

The case upon which British Airways relies to counter

this conclusion, see Barclay v. British Airways plc, [2008] EWCA

(Civ) 1419, [2010] QB 187, 2008 WL 5240582 (Eng.), does not assist

its cause. There, the England and Wales Court of Appeal held that

the passenger's injuries were not caused by an "accident" under

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Article 17(1) when the plaintiff's foot "slipped" on "a narrow

plastic strip running under the seats and covering . . . the seat

fix tracking." Id. ¶¶ 4-5, 36. Whether the presence of such a

plastic strip was expected — as it might well have been — says

nothing about whether disembarking on the staircase that British

Airways compelled the plaintiff to use was expected. And at any

rate, the court's inquiry in Barclay focused on whether the slip

itself may qualify as the "event" constituting the "accident" under

Article 17(1), id. ¶¶ 30, 34-35, a question not presented in this

appeal.

III

There is one loose end. The plaintiff also appeals the

district court's denial of her (untimely) motion for partial

summary judgment. As we have explained, however, the record

reveals "contradictory evidence" as to whether an accident took

place, which precludes summary judgment for either party on the

Montreal Convention claim. Saks, 470 U.S. at 405.

The plaintiff seeks to forestall this fate by pointing

to certain paragraphs in her statement of material facts, which

she argues should have been deemed admitted because British Airways

allegedly failed to contest them. See D. Mass. R. 56.1. This

argument leads nowhere. Even assuming that those paragraphs should

have been deemed admitted, the outcome is the same. Those

paragraphs do little more than recapitulate the plaintiff's

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general narrative and certain conclusions of her expert. Nothing

in the plaintiff's statement of facts conclusively establishes

that there was an accident within the meaning of the Montreal

Convention. We therefore uphold the district court's denial of

the plaintiff's cross-motion for partial summary judgment.

IV

We need go no further. On this scumbled record, it is

for a jury to decide whether the plaintiff's injuries resulted

from an accident within the meaning of the Montreal Convention.

It follows that the district court erred in granting summary

judgment in favor of British Airways. Consequently, we vacate

that judgment. For essentially the same reason, we affirm the

district court's denial of the plaintiff's motion for partial

summary judgment. And in the end, we remand for further

proceedings consistent with this opinion. Two-thirds costs shall

be taxed in favor of the plaintiff.

Affirmed in part, vacated in part, and remanded.

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