Feliciano v. Department Of Transportation

P R E L I M I N A R Y P R I N T
Volume 605 U. S. Part 1
Pages 38–72
OFFICIAL REPORTS
OF
T H E S U P R E M E C O U R T
April 30, 2025
REBECCA A. WOMELDORF
reporter of decisions
Page Proof Pending Publication
N O T I C E : This preliminary print is subject to formal revision before
the bound volume is published. Users are requested to notify the Reporter
of Decisions, Supreme Court of the United States, Washington, D. C. 20543,
pio@supremecourt.gov, of any typographical or other formal errors.

Page Proof Pending Publication
38 OCTOBER
TERM, 2024
Syllabus
FELICIANO v. DEPARTMENT OF TRANSPORTATION
certiorari
to the united states court of appeals for
the federal circuit
No. 23–861. Argued December 9, 2024—Decided April 30, 2025
Tens of thousands of federal civilian employees serve the Nation as mili-
tary reservists. When called to active duty, these reservists often re-
ceive less pay than they earn in their civilian jobs. To address this gap,
Congress adopted a “differential pay” statute requiring the government
to make up the difference between a federal civilian employee's military
and civilian pay in various circumstances, including when the reservist
is called to active duty “during a national emergency.” At issue here
is whether this language guarantees differential pay when a reservist
serves on active duty while a national emergency is ongoing, or whether
it requires proving a “substantive connection” between the service and
a particular national emergency.
Petitioner Nick Feliciano, an air traffc controller with the Federal
Aviation Administration, also served as a Coast Guard reserve petty
offcer. In July 2012, the Coast Guard ordered him to active duty under
10 U. S. C. § 12301(d), which authorizes activation of reservists with
their consent. He remained on active duty until February 2017, serv-
ing aboard a Coast Guard ship escorting vessels to and from harbor.
His orders noted that he was called to active duty “in support of ” sev-
eral “contingency operation[s],” including Operations Iraqi Freedom and
Enduring Freedom. Throughout this period, Feliciano did not receive
differential pay for his service pursuant to orders under § 12301(d).
After the Merit Systems Protection Board rejected his differential-pay
claim, he appealed to the Federal Circuit.
Feliciano argued that two statutes entitled him to differential pay: 5
U. S. C. § 5538(a) and 10 U. S. C. § 101(a)(13)(B). Section 5538(a) re-
quires differential pay for federal civilian employee reservists ordered
to ac tive duty “under . . . a prov isi on of law referred to in”
§ 101(a)(13)(B). Section 101(a)(13)(B) defnes “contingency operation” to
include operations that result in the call to active duty of servicemem-
bers under several enumerated statutes “or any other provision of law
during a war or during a national emergency declared by the President or
Congress.” While acknowledging he was not called up under any of the
specifcally listed statutes, Feliciano contended that the fnal phrase enti-
tled him to differential pay because he was ordered to active duty under
“any other provision of law” (§ 12301(d)) “during a national emergency.”

Page Proof Pending Publication
Cite
as: 605 U. S. 38 (2025)
39
Syllabus
The Federal Circuit disagreed. Following its earlier decision in
Adam
s v. Department of Homeland Security, 3 F. 4th 1375, the court
held that when a reservist seeks differential pay for service “during a
national emergency,” he must show not only that he served while a
national emergency was ongoing, but also that a substantive connection
linked his service to a particular national emergency.
Held: A federal civilian employee called to active duty pursuant to “any
other provision of law . . . during a national emergency” as described in
§ 101(a)(13)(B) is entitled to differential pay if the reservist's service
temporally coincides with a declared national emergency without any
showing that the service bears a substantive connection to a particular
emergency. Pp. 44–56.
(a) Several considerations support this interpretation. First, the
word “during ” normally “denotes a temporal link” and means “contem-
poraneous with.” United States v. Ressam, 553 U. S. 272, 274–275. It
does not generally imply any substantive connection. Absent evidence
that Congress intended a specialized meaning, those governed by law
are entitled to rely on its ordinary meaning. Pp. 44–46.
(b) Contextual clues strengthen this conclusion. When Congress in-
tends to require both temporal and substantive connections, it has done
so expressly, using phrases like “during and in relation to” or “during
and because of ” in various statutes. So the absence of any words hint-
ing at a substantive connection in the statute at issue here supplies a
telling clue that it operates differently and imposes a temporal condition
alone. See Ysleta del Sur Pueblo v. Texas, 596 U. S. 685, 704. Addi-
tionally, one of the specifc provisions that can trigger differential pay, 10
U. S. C. § 12302, authorizes activation of reservists “[i]n time of national
emergency”—language the government contends speaks only tempo-
rally. If that phrase requires no substantive connection, it is implausi-
ble that “during a national emergency” in § 101(a)(13)(B) would do so.
Moreover, requiring a substantive connection would create interpretive
diffculties, as the statute provides no principled way to determine what
kind of substantive connection would suffce. The government's inter-
pretation would also create tension with 18 U. S. C. § 209, potentially
criminalizing differential pay given by private employers to reservists,
even though nothing in the phrase “during a national emergency” tells
a private employer that a substantive connection is required, let alone
what sort of connection must exist. Finally, when the Congressional
Budget Offce scored similar legislation to help Congress understand the
likely impact of proposed legislation, it calculated costs based on “the
total number of reservists on active duty,” not just those engaged in
emergency-related duties. CBO's approach provides further evidence

Page Proof Pending Publication
40 FELICIANO
v. DEPARTMENT OF TRANSPORTATION
Syllabus
of how an ordinary reader might have understood the statutory lan-
g
uage at issue here. Pp. 46–48.
(c) The government's counterarguments are unpersuasive. First, al-
though the word “during ” can sometimes imply more than a temporal
connection depending on context, in this statutory context a purely tem-
poral relationship is meaningful. A reservist's active-duty service dur-
ing a national emergency bolsters the government's capacity to address
that emergency whether or not his service directly relates to it. Sec-
ond, the government's surplusage argument—that a temporal-only read-
ing would render the phrase meaningless given the perpetual existence
of national emergencies—fails for several reasons: The interpretation
leaves no part of the statute without work to do; the argument depends
on contingent factual assumptions about the permanence of emergency
declarations; similar statutes use temporal language without requiring
substantive connections; and the statute provides no principled way to
determine what kind of substantive connection would suffce. Finally,
the potential policy consequences the government highlights cannot
overcome the statute's most natural reading. Pp. 49–56.
Reversed and remanded.
Gorsuch, J., delivered the opinion of the Court, in which Roberts, C.
J., and Sotomayor, Kavanaugh, and Barrett, JJ., joined. Thomas, J.,
fled a dissenting opinion, in which Alito, Kagan, and Jackson, JJ.,
joined, post, p. 56.
Andrew T. Tutt argued the cause for petitioner. With him
on the briefs were John P. Elwood, Daniel Yablon, Matthew
L. Farley, and Brian J. Lawler.
Nicole Frazer Reaves argued the cause for respondent.
With her on the brief were Solicitor General Prelogar, Prin-
cipal Deputy Assistant Attorney General Boynton, Deputy
Solicitor General Fletcher, and Geoffrey M. Long.*
*Briefs of amici curiae urging reversal were fled for the State of Texas
et al. by Ken Paxton, Attorney General of Texas, Brent Webster, First
Assistant Attorney General, Aaron L. Nielson, Solicitor General, Kyle D.
Highful, Assistant Solicitor General, and J. Andrew Mackenzie, Assistant
Attorney General, by Alan Wilson, Attorney General of South Carolina,
Robert D. Cook, Solicitor General, J. Emory Smith, Jr., Deputy Solicitor
General, and Thomas T. Hydrick and Joseph D. Spate, Assistant Deputy
Solicitors General, and by the Attorneys General for their respective juris-
dictions as follows: Kris Mayes of Arizona, Tim Griffn of Arkansas,

Cite
as: 605 U. S. 38 (2025)
41
Opinion of the Court
Justice Gorsuch delivered the opinion of the Court.
T
ens of thousands of federal civilian employees serve
the Nation as military reservists. When the military calls
those reservists to active duty, it often pays them less
than they earn in their civilian jobs. Seeking to address
that gap, Congress some years ago adopted a “differential
pay” statute. That law requires the government to make
up the difference between a federal civilian employee's mili-
tary and civilian pay in various circumstances, including
when he is called to active duty “during a national emer-
gency.” The question we face concerns the meaning of that
quoted language. Does it guarantee a reservist differen-
tial pay when he serves on active duty while a national emer-
gency is ongoing, or does it require a reservist to prove
that his service bears a “substantive connection” to a par-
ticular national emergency?
I
Nick Feliciano began working for the Federal Aviation Ad-
ministration as an air traffc controller in 2005. App. to Pet.
for Cert. 9a. At the same time, Mr. Feliciano served as a
reserve petty offcer in the United States Coast Guard.
Ibid.; Brief for Respondent 6. In July 2012, the Coast
Philip J. Weiser of Colorado, William Tong of Connecticut, Brian L.
Schwalb of the District of Columbia, Ashley Moody of Florida, Kwame
Raoul of Illinois, Brenna Bird of Iowa, Russell Coleman of Kentucky,
Anthony G. Brown of Maryland, Keith Ellison of Minnesota, Lynn Fitch
of Mississippi, Michael T. Hilgers of Nebraska, Dave Yost of Ohio, Ellen
F. Rosenblum of Oregon, Michelle A. Henry of Pennsylvania, Jonathan
Skrmetti of Tennessee, Jason S. Miyares of Virginia, Patrick Morrisey of
West Virginia, and Josh Kaul of Wisconsin; for the American Federation
of Government Employees by Matthew W. Milledge, David A. Borer, and
Andres M. Grajales; for Members of Congress by Timothy Taylor and
Sarah Kelly-Kilgore; for Military-Veterans Advocacy, Inc., by Melanie L.
Bostwick and John B. Wells; for the National Law School Veterans Clinic
Consortium by Katie M. Becker and Brent G. Filbert; and for the Reserve
Organization of America by Scott A. Felder.
Page Proof Pending Publication

Page Proof Pending Publication
42 FELICIANO
v. DEPARTMENT OF TRANSPORTATION
Opinion of the Court
Guard ordered him to active-duty service and, for the most
par
t, he remained on active duty until February 2017. App.
to Pet. for Cert. 14a.
During much of that period, the statutory authority for
Mr. Feliciano's active-duty service came from 10 U. S. C.
§ 12301(d). As a general matter, that provision authorizes
the activation of reservists with their consent. Mr. Feli-
ciano's § 12301(d) orders noted that he was called to active
duty to serve “in support of ” several “contingency opera-
tion[s],” including Operation Iraqi Freedom and Operation
Enduring Freedom. App. to Pet. for Cert. 33a, 75a–76a;
Brief for Respondent 7. Throughout his active-duty serv-
ice, Mr. Feliciano served onboard a Coast Guard ship escort-
ing other vessels to and from harbor. Brief for Petitioner 8;
Brief for Respondent 6.
While Mr. Feliciano served on active duty pursuant to or-
ders under § 12301(d), the government did not afford him dif-
ferential pay. App. to Pet. for Cert. 31a, 34a–37a. Eventu-
ally, that led Mr. Feliciano to seek relief from the Merit
Systems Protection Board. Id., at 8a, 34a–37a. There, he
claimed the FAA had created a hostile work environment
and unlawfully denied him differential pay during the time
he spent serving on active duty under § 12301(d). After the
Board rejected his claims, see id., at 29a–30a, 37a, Mr. Felici-
ano appealed to the Federal Circuit.
On appeal, Mr. Feliciano argued that two statutes entitled
him to differential pay: 5 U. S. C. § 5538(a) and 10 U. S. C.
§ 101(a)(13)(B). See Brief for Petitioner in No. 2022–1219
(CA Fed., Apr. 29, 2022), ECF Doc. 21, p. 19. As relevant
here, § 5538(a) requires the government to provide differen-
tial pay to a federal civilian employee reservist when the
military orders him to active-duty service “under . . . a provi-
sion of law referred to in section 101(a)(13)(B) of title 10” of
the U. S. Code. Section 101(a)(13)(B), in turn, forms part
of the defnition of the phrase “contingency operation.” A
contingency operation, that statute says, includes a “military

Cite
as: 605 U. S. 38 (2025)
43
Opinion of the Court
operation that . . . results in the call or order to . . . active
duty
of members of the uniformed services under section
688, 12301(a), 12302, 12304, 12304a, 12305, or 12406 of [title
10], chapter 13 of [title 10], section 3713 of title 14, or any
other provision of law during a war or during a national
emergency declared by the President or Congress.” (Em-
phasis added.)
1
Though Mr. Feliciano acknowledged that he was not called
up under any of the specifc statutes listed in § 101(a)(13)(B),
he argued that the statute's closing words, italicized above,
entitled him to differential pay. After all, the Coast Guard
called him to active duty under another “provision of law”
(§ 12301(d)), and his orders came “during a national emer-
gency.” ECF Doc. 21, at 21–23. As a result, he contended,
he served pursuant to a call to active duty under “a provi-
sion of law referred to in 10 U. S. C. § 101(a)(13)(B),” and
was thus entitled to differential pay under § 5538(a). Id.,
at 19, 23.
The Federal Circuit disagreed. Citing its earlier decision
in Adams v. Department of Homeland Security, 3 F. 4th
1375 (2021), the court reasoned that, when a reservist seeks
differential pay for service “during a national emergency,”
he must show not only that he served on active duty while
a national emergency was ongoing. He must also show a
substantive connection between his service and a particular
national emergency. App. to Pet. for Cert. 4a. Because
Mr. Feliciano had not made that second showing, the court
held, he was not entitled to differential pay. Id., at 3a–4a.
1
Section 101(a)(13)(A) forms the other part of the defnition of the
phrase “contingency operation.” It provides that “contingency opera-
tion” also includes “a military operation that . . . is designated by the
Secretary of Defense as an operation in which members of the armed
forces are or may become involved in military actions, operations, or hos-
tilities against an enemy of the United States or against an opposing mili-
tary force.” Notably, however, 5 U. S. C. § 5538(a) does not reference this
provision for purposes of determining when differential pay is due.
Page Proof Pending Publication

44 FELICIANO
v. DEPARTMENT OF TRANSPORTATION
Opinion of the Court
Mr. Feliciano sought review of the Federal Circuit's deci-
si
on, and we agreed to take his case. 602 U. S. 1037 (2024).
II
At its core, the dispute before us turns on the meaning of
the phrase “during a national emergency.” Does that lan-
guage promise differential pay to certain federal civilian em-
ployees called to active-duty service while a national emer-
gency is ongoing, as Mr. Feliciano argues? Or does it
require a reservist to prove some additional, substantive
connection between his service and a particular national
emergency, as the Federal Circuit held and the government
contends? Several considerations persuade us that Mr.
Feliciano's interpretation is the sounder one.
A
Start with the word “during.” Normally, we have said,
that word “denotes a temporal link” and means “contempora-
neous with.” United States v. Ressam, 553 U. S. 272, 274–
275 (2008). Any number of dictionaries from around the
time of § 101(a)(13)(B)'s adoption in 1991 offer up similar for-
mulations. See, e. g., Black's Law Dictionary 504 (6th ed.
1990) (defning “during ” as “[t]hroughout the course of;
throughout the continuance of; in the time of; after the com-
mencement and before the expiration of ”).
2
Conversely, the word “during ” does not generally imply a
substantive connection. The government itself has pre-
2
Accord, Random House Dictionary of the English Language 608 (2d ed.
1987) (during: “throughout the duration, continuance, or existence of ” or
“at some time or point in the course of ”); Webster's Third New Interna-
tional Dictionary 703 (1993) (during: “throughout the continuance or
course of ” or “at some point in the course of ”); American Heritage Diction-
ary 572 (3d ed. 1992) (during: “[t]hroughout the course or duration of ”
or “[a]t some time in”). Dictionaries from the time of § 5538's enactment
in 2009 say the same. See, e. g., American Heritage Dictionary 556 (4th
ed. 2006) (during: “[t]hroughout the course or duration of ” or “[a]t some
time in”).
Page Proof Pending Publication

Page Proof Pending Publication
Cite
as: 605 U. S. 38 (2025)
45
Opinion of the Court
viously acknowledged as much. As its briefng in Ressam
explai
ned, “[t]he plain everyday meaning of `during ' is `at
the same time' or `at a point in the course of.' It does not
normally mean `at the same time and in connection with.' ”
Brief for United States in United States v. Ressam, O. T.
2007, No. 455, pp. 13–14 (emphasis added). Reading “dur-
ing ” to require a substantive connection, the government
warned, risks “read[ing] in a relational element” that the
word does not necessarily convey. Tr. of Oral Arg. in
United States v. Ressam, O. T. 2007, No. 455, p. 31. Adopt-
ing just that view, this Court in Ressam held that a sentenc-
ing enhancement addressing those who carry an explosive
“during ” the commission of a felony applies to individuals
who carry explosives “contemporaneous with” their felonies
even in the absence of a substantive “relationship between
the explosive carried and the underlying felony.” 553 U. S.,
at 275.
Sometimes, to be sure, statutory terms can carry meanings
that depart from their ordinary ones. Congress may, for ex-
ample, defne a word or phrase in a specialized way or em-
ploy a term of art with long-encrusted connotations in a
given feld. See, e. g., Department of Agriculture Rural De-
velopment Rural Housing Service v. Kirtz, 601 U. S. 42, 59–
60 (2024); Sekhar v. United States, 570 U. S. 729, 733 (2013).
But we have no evidence of anything like that here. And
absent such evidence, those whose lives are governed by law
are entitled to rely on its ordinary meaning, not left to specu-
late about hidden messages. See, e. g., Henson v. Santander
Consumer USA Inc., 582 U. S. 79, 86 (2017); Niz-Chavez v.
Garland, 593 U. S. 155, 163 (2021).
Given all that, we think Mr. Feliciano's reading more con-
sistent with the statutory language before us. Just ask
yourself how an ordinary American might approach the law's
terms. Would he have any reason to think that a reservist
called up to active duty “during ” a national emergency is
entitled to differential pay if, and only if, he can prove his

46 FELICIANO
v. DEPARTMENT OF TRANSPORTATION
Opinion of the Court
service has a “substantive connection” to a particular emer-
gency?
We doubt it.
B
Strengthening our conviction on this score are a number
of contextual clues.
First, compare the statute before us with other laws.
When insisting on both a temporal and a substantive connec-
tion in other settings, Congress has commonly made its point
expressly. Up and down the federal criminal code, for in-
stance, statutes speak of actions taken “during and in rela-
tion to” specifed criminal conduct. 18 U. S. C. § 924(c)(1)(A)
(emphasis added); see a lso, e. g., §§ 115( b)(1)(B)( iv),
924(c)(5), 929(a)(1). When it comes to statutes governing
the Armed Forces, Congress has used the phrase “during
and because of ” to describe leave both contemporaneous
with and related to a reservist's active-duty service. 5
U. S. C. § 6323(b)(2)(B) (emphasis added). Congress, too, has
exempted from certain statutory requirements the govern-
ment's acquisition of land when it takes place both “during
a national emergency” and “for national defense purposes.”
7 U. S. C. § 4208(b) (emphasis added). As these examples il-
lustrate, Congress can and does use different words in differ-
ent provisions to insist on a substantive connection. But the
absence of any words hinting at a substantive connection in
the statute before us supplies a telling clue that it operates
differently and imposes a temporal condition alone. See Ys-
leta del Sur Pueblo v. Texas, 596 U. S. 685, 704 (2022).
Next, consider another provision that can trigger differen-
tial pay. Recall that the differential-pay statute—5 U. S. C.
§ 5538—not only works in concert with § 101(a)(13)(B) to en-
sure differential pay for certain reservists ordered to active
duty “during a national emergency.” It also guarantees dif-
ferential pay for other reservists called up under specifc
statutes listed in § 101(a)(13)(B). See Part I, supra. One
such statute, 10 U. S. C. § 12302, authorizes the activation of
various reservists “[i]n time of national emergency.” The
Page Proof Pending Publication

Page Proof Pending Publication
Cite
as: 605 U. S. 38 (2025)
47
Opinion of the Court
government contends that this language speaks only tempo-
ra
lly. See Tr. of Oral Arg. 61–62. But if that is true and
the phrase “[i]n time of a national emergency” in § 12302 re-
quires no substantive connection, how might “during a na-
tional emergency” in § 101(a)(13)(B) do so? If a plausible ex-
planation exists for interpreting the one phrase, but not the
other, to require a substantive connection, the government
does not supply it.
Notice, as well, the questions that would follow from insist-
ing on a substantive connection here. To prove a substan-
tive connection, the government suggests, a reservist must
show that he served in support of a contingency operation
while on active duty. Brief for Respondent 23–24; Tr. of
Oral Arg. 75–76; post, at 71 (Thomas, J., dissenting) (arguing
the same). But the Federal Circuit applies a more demand-
ing test. On its view, a reservist must show that he served
directly in a contingency operation to merit differential pay.
See App. to Pet. for Cert. 4a; Adams, 3 F. 4th, at 1379. How
might we choose between these two rules? The statute
does not say. And the fact that Congress supplied no princi-
pled way to determine what kind of substantive connection
is necessary strikes us as yet another sign that the law does
not require any such connection.
Also relevant, to our minds, is how the parties' competing
interpretations interact with 18 U. S. C. § 209. As a rule,
that law makes it a crime for a private party to supplement
a federal employee's salary. See § 209(a). At the same
time, the statute offers an important exception: It allows
a pr ivate par ty to offer di fferentia l pay to a reserv ist-
employee “on active duty pursuant to a call or order to active
duty under a provision of law referred to” in 10 U. S. C.
§ 101(a)(13). 18 U. S. C. § 209(h). On the government's
reading of § 101(a)(13)(B), a private employer would appar-
ently commit a federal crime by providing differential pay to
a reservist on active-duty service while a national emer-
gency is ongoing—unless, of course, the reservist's service

48 FELICIANO
v. DEPARTMENT OF TRANSPORTATION
Opinion of the Court
bears a substantive connection to a particular national emer-
gency
. But what in the phrase “during a national emer-
gency” tells a private employer that a substantive connection
is required, let alone what sort of connection it must be?
3
Finally, adding to the case against the government's inter-
pretation are the views of others who have come this way
before us. The Congressional Budget Offce (CBO) provides
cost estimates to help Members of Congress understand the
likely impact of their proposed legislation. See, e. g., Con-
gressional Research Service, J. Saturno, Introduction to the
Federal Budget Process 19 (Jan. 10, 2023). And when CBO
scored potential legislation featuring terms that largely mir-
ror those now at issue here, it based its calculations on “the
total number of reservists on active duty,” not those who
are personally engaged in emergency-related duties. CBO,
Cost Estimate, S. 593: Reservist Pay Security Act of 2004,
pp. 2–3 (Aug. 4, 2004) (emphasis added); see also CBO, Cost
Estimate, S. 2400: Ronald W. Reagan National Defense Au-
thorization Act for Fiscal Year 2005, p. 9 (July 21, 2004). Of
course, no one votes for CBO reports, and courts charged
with interpreting the law owe those estimates no rote defer-
ence. But CBO's approach does provide further evidence of
how an ordinary reader might have understood the statutory
language at issue here around the time of the differential-
pay statute's adoption. See A. Scalia & B. Garner, Reading
Law: The Inter pret ati on of Lega l Texts 388 (2012)
(Scalia & Garner).
3
At oral argument, the government suggested that an employer who
mistakenly provides differential pay to a reservist without confrming that
his service has the requisite substantive connection to a particular emer-
gency might escape liability for lack of a suffcient mens rea to warrant a
conviction. See Tr. of Oral Arg. 45–46; see also United States v. Project
on Government Oversight, 616 F. 3d 544, 556–557 (CADC 2010). Maybe
so. But that still leaves unanswered the question whether the statute
fairly informs an employer what is (and is not) proscribed.
Page Proof Pending Publication

Cite
as: 605 U. S. 38 (2025)
49
Opinion of the Court
III
The
government and our dissenting colleagues see things
differently. They insist that the phrase “during a national
emergency” requires a substantive connection between a re-
servist's service and a particular national emergency. To
our minds, however, the government and the dissent do not
adequately grapple with the textual and contextual evidence
we have set forth. They give short shrift to Ressam and
the ordinary meaning of the word “during.” They brush
aside other statutes showing that Congress knows how to
impose a substantive connection when it wishes. They do
not convincingly explain how § 12302 might be read to re-
quire only a temporal connection but “during a national
emergency” must be read to demand more. They discount
CBO's practice. And they nowhere offer a principled basis
for preferring the substantive connection they propose over
the alternative the Federal Circuit offered.
To be sure, the three central arguments the government
and the dissent pursue are not entirely without force. But
even on their own terms, each suffers defciencies and, to our
eyes, none suffces to overcome the competing evidence of
statutory meaning we have outlined.
A
The government and the dissent begin by observing that,
in at least some contexts, the word “during ” can imply more
than a temporal connection. Brief for Respondent 14–17;
see post, at 59–60 (opinion of Thomas, J.). To illustrate the
point, the government asks us to imagine a statute that “re-
ferred to any attorney who argues `during ' a court hearing.”
Brief for Respondent 14. A reader would, the government
posits, understand that language “to include only attorneys
who argue in the course of the hearing—not those who argue
elsewhere while the hearing happens to be occurring.”
Ibid.
Page Proof Pending Publication

50 FELICIANO
v. DEPARTMENT OF TRANSPORTATION
Opinion of the Court
It's a fair observation. Context plays a vital role when
i
nterpreting statutes. And, in the context of the govern-
ment's hypothetical law, we agree that an ordinary reader
would understand it to require both a temporal and substan-
tive connection between an attorney's argument and the
court hearing. Really, without a substantive connection, the
government's imagined statute would be meaningless, cap-
turing any attorney who happens to argue anywhere in any
forum at the same time as the ongoing hearing. The same
goes for the dissent's example of a statute defning a “ `cap-
tured record' ” to mean “ `material captured during combat
operations.' ” Post, at 60 (opinion of Thomas, J.) (quoting 10
U. S. C. § 427(g)(1)). There, too, an ordinary reader would
understand Congress as referring only to records captured
in the course of combat operations, not to all records cap-
tured while combat was ongoing somewhere, for without that
substantive connection the statute would be senseless.
But we fail to see how that observation translates here.
In this statutory context, a purely temporal relationship is
meaningful. After all, a reservist's active-duty service dur-
ing a national emergency bolsters the government's capacity
to address that emergency; his work on everyday matters
may free up others to handle emergent ones. Notably, the
government itself argues that Congress has sometimes taken
just this view, promising differential pay to certain reserv-
ists called to active duty “in time of national emergency,”
whether or not their service bears a substantive connection
to a particular emergency. See Part II–B, supra (discussing
10 U. S. C. § 12302). In this context, then, unlike in some
others, reading the word “during ” to speak only temporally
is perfectly sensible.
4
4
Pursuing a similar argument from statutory context, the dissent sub-
mits that, because the phrase “contingency operation” implies some “exi-
genc[y]” as a matter of “ordinary” usage, the word “during ” must entail a
substantive connection. See post, at 61–63 (opinion of Thomas, J.). But
none of that follows. The phrase “contingency operation” is subject to an
Page Proof Pending Publication

Cite
as: 605 U. S. 38 (2025)
51
Opinion of the Court
B
N
ext, the government and the dissent invoke the surplus-
age canon. If the phrase “during a national emergency” re-
quired only a temporal overlap, the government and the dis-
sent say, it would do practically no work. After all, the
argument goes, there are dozens of declared emergencies
today, some have been on the books for years, and it is “un-
likely that there will ever be a time when no national emer-
gency exists.” Brief for Respondent 18–19; post, at 63–67
(opinion of Thomas, J.). The only way to give the phrase
“during a national emergency” work to do, we are told, is to
interpret it to require a substantive connection.
Here, again, the government and the dissent have some-
thing of a point. With the exception of a brief period in the
1970s, one declared national emergency or another has been
ongoing in this country for many decades. Brief for Re-
spondent 18; post, at 63 (Thomas, J., dissenting). Even so,
this line of argument does not persuade us for a few reasons
taken in combination.
For one thing, the surplusage canon is primarily a tool of
linguistic interpretation, refecting an assumption applicable
to “all sensible writing: Whenever a reading arbitrarily ig-
express statutory defnition, to which we must adhere “even if it varies
from a term's ordinary meaning.” Digital Realty Trust, Inc. v. Somers,
583 U. S. 149, 160 (2018). That defnition includes a military operation
that results in a call to active duty under certain specifcally enumerated
statutory authorities or under any other law “during a national emer-
gency.” As even the dissent admits, some of the specifcally enumerated
statutory authorities are “not pegged to [a] specifc exigenc[y].” Post, at
62 (opinion of Thomas, J.). By way of example, consider again 10 U. S. C.
§ 12302, which the government says allows it to call reservists to active
duty “[i]n time of national emergency” regardless whether their service
bears a substantive connection to any particular emergency. And if the
specifcally enumerated statutory authorities that help defne a “contin-
gency operation” do not always demand a substantive connection between
a reservist's service and a particular emergency, we see no reason why
the phrase “during a national emergency” must.
Page Proof Pending Publication

52 FELICIANO
v. DEPARTMENT OF TRANSPORTATION
Opinion of the Court
nores linguistic components or inadequately accounts for
them,
the reading may be presumed improbable.” Scalia &
Garner 174 (internal quotation marks omitted). Nothing in
our interpretation of § 101(a)(13)(B) defes that general rule
of construction. When a reservist is called to active duty
under one of the statutes enumerated in § 101(a)(13)(B),
§ 5538(a) guarantees him differential pay. And when a re-
servist is called to active duty under “any other provision
of law, ” he is entitled to di fferentia l pay only i f a na-
tional emergency (or war) is ongoing. See 10 U. S. C.
§ 101(a)(13)(B); 5 U. S. C. § 5538(a). Linguistically, our read-
ing leaves no part of the statute ignored or left without work
to do.
For another, the government and dissent's practical (not
linguistic) superfuity argument depends on a contingent fac-
tual assumption. Imagine Congress and the President de-
cided tomorrow to end all existing emergencies. No one
disputes that our reading of the statute would perform
practically signifcant work in those circumstances, effec-
tively denying differential pay to reservists called to active
duty under “any other provision of law.” 10 U. S. C.
§ 101(a)(13)(B). But, the government and the dissent insist,
we should ignore that possibility because emergencies have
become an immutable feature of modern governance. See
Tr. of Oral Arg. 43; post, at 63 (opinion of Thomas, J.).
Maybe so, but maybe not. In the 1970s, the elected
branches did something nearly like what the government
today considers unthinkable. In 1976, Congress passed and
President Ford signed the National Emergencies Act, which
effectively ended then-existing emergencies and established
procedures for declaring (and concluding) new ones. See 90
Stat. 1255 (codifed at 50 U. S. C. § 1601 et seq.); Congres-
sional Research Service, E. Webster, National Emergency
Powers 7–11 (Nov. 19, 2021). In spite of that intervention,
of course, the number of declared emergencies has only
grown in the years since. But history may yet repeat itself,
Page Proof Pending Publication

Page Proof Pending Publication
Cite
as: 605 U. S. 38 (2025)
53
Opinion of the Court
even if the government today considers the prospect “un-
l
ikely.” Brief for Respondent 19. And it is unclear why we
should overlook the most natural linguistic interpretation of
this statute's terms based on an assumption that prevailing
factual conditions will never change. What is a present fact
of the world is not necessarily a permanent one.
For another thing still, the government and dissent's ap-
proach invites its own superfuity problems. A number of
statutes tie a governmental power or duty to the existence
of some ongoing national emergency. For example, Con-
gress has made certain contracting authorities available to
the Executive Branch “during a national emergency.” 50
U. S. C. § 1435. And, as we have seen, Congress has prom-
ised differential pay to certain other reservists called to ac-
tive duty “[i]n time of national emergency.” See Part II–B,
supra. The government maintains that these statutes do
not require a substantive connection, only a temporal over-
lap, with a national emergency. See Brief for Respondent
30; Tr. of Oral Arg. 61–62. Yet, under the government and
dissent's view, Congress was wasting its breath with super-
fuous language in all these laws. A more natural inference,
we believe, is that Congress sometimes considers a purely
temporal link with a national emergency a salient condition
on governmental powers and duties, even if that condition
will often be satisfed.
Finally, even if we could somehow overcome all of these
problems, we would only fnd ourselves facing again the
question of what kind of substantive tie a reservist's service
must have to a national emergency. And, as we have dis-
cussed, the statute supplies no obviously principled way for
us to resolve what that connection might be. See Part II–
B, supra.
5
5
The dissent also insists that our reading would render superfuous vari-
ous postenactment amendments that have expanded the list of provisions
enumerated in § 101(a)(13)(B). Post, at 65–67 (opinion of Thomas, J.).
That argument is mistaken for reasons already discussed: Each of the

54 FELICIANO
v. DEPARTMENT OF TRANSPORTATION
Opinion of the Court
C
F
ailing all else, the government and the dissent worry that
our interpretation would invite anomalous policy conse-
quences. Brief for Respondent 22; post, at 68 (opinion of
Thomas, J.) (expressing concern about the potential “rip-
ple effects” of our decision). So, for example, the govern-
ment fears that a purely temporal reading of the phrase
“during a national emergency” might require it to provide
differential pay to a reservist called to active duty to face
a court-martial. Brief for Respondent 22–23. Likewise,
the government says, our reading could require differen-
tial pay for a reservist called up to attend “training for
new Judge Advocates at the Judge Advocate General's
Legal Center and School in Charlottesville, Virginia.” Id.,
at 23.
But what does any of that prove? When a party claims
that a law yields anomalous policy consequences, its usual
recourse lies in Congress, not in the courts where litigants
are generally entitled to expect that statutes will “be en-
forced as written.” Epic Systems Corp. v. Lewis, 584 U. S.
497, 525 (2018); see also Patel v. Garland, 596 U. S. 328, 346
(2022) (“[P]olicy concerns cannot trump the best interpreta-
tion of the statutory text”).
amendments the dissent cites promises differential pay even in the ab-
sence of any national emergency. The only possible exception concerns
an amendment that, among other things, authorized differential pay retro-
actively for certain members of the Coast Guard for a single year, a year
in which there was already an ongoing national emergency. Post, at 66
(Thomas, J., dissenting) (discussing § 681(a), 126 Stat. 1795). But even
assuming that one aspect of that single amendment may represent “some
redundancy” on our account of § 101(a)(13)(B), the dissent's interpretation
results in redundancies of its own and encounters so many other diffcul-
ties that we think the “better overall reading of the statute” remains the
one we pursue. Rimini Street, Inc. v. Oracle USA, Inc., 586 U. S. 334,
346 (2019).
Page Proof Pending Publication

Cite
as: 605 U. S. 38 (2025)
55
Opinion of the Court
Nor, even taken on their own terms, are the potential con-
sequences
the government highlights all that anomalous.
Members of the Armed Forces facing court-martial are en-
titled to their military wages until convicted, 10 U. S. C.
§ 857(a)(1), and they are presumed innocent until proven
guilty, § 851(c)(1). In light of those statutory directions, it
is hardly absurd to think Congress might have also wanted
a reservist to receive differential pay when called to active
duty to answer a court-martial that might acquit him. Much
the same goes for reservists called to active duty for train-
ing. Whether that training entails learning the fner points
of the Uniform Code of Military Justice or attending Air-
borne School, well-trained reservists are ones the Nation can
call on at a moment's notice, as it often has. See, e. g., Brief
for State of Texas et al. as Amici Curiae 20 (“Within min-
utes of the September 11 attacks, National Guard and Re-
servists responded to the call to duty”).
6
*
In the end, we are persuaded that the statutory language
means what its terms most naturally suggest: A federal ci-
vilian employee called to active duty pursuant to “any other
provision of law . . . during a national emergency” is entitled
to differential pay without having to prove that his service
6
The dissent expresses concern that our interpretation might lead to
other “untold consequences,” like expanding the “availability of civilian
court[s]-martial” or exempting the Department of Defense from having to
notify Congress before entering into certain real-estate transactions.
Post, at 63 (opinion of Thomas, J.) (citing 10 U. S. C. §§ 802(a)(10) and
2662(f )(1)(E)). We express no views on the dissent's claims except to ob-
serve two things. First, as the dissent acknowledges, considerations of
constitutional avoidance might counsel in favor of a narrowing construc-
tion of certain laws governing courts-martial. See post, at 63 (opinion of
Thomas, J.). Second, the result the dissent posits with respect to real-
estate transactions is neither unthinkable nor something Congress could
not alter to the extent the Constitution allows.
Page Proof Pending Publication

56 FELICIANO
v. DEPARTMENT OF TRANSPORTATION
Thomas, J., dissenting
was substantively connected in some particular way to some
par
ticular emergency. Because the Federal Circuit held
otherwise, its judgment is reversed, and the case is re-
manded for further proceedings consistent with this opinion.
It is so ordered.
Justice Thomas, with whom Justice Alito, Justice
Kagan, and Justice Jackson join, dissenting.
Federal civilian employees who also serve as military re-
servists are entitled to “differential pay” when they are
called to active-duty service “during a national emergency.”
See 5 U. S. C. § 5538; 10 U. S. C. § 101(a)(13)(B). Differential
pay compensates such reservists for the difference between
their military and civilian salaries when active-duty service
would otherwise cause a pay cut. The question before us
is what Congress meant by the phrase “during a national
emergency.” Depending on the context, that phrase could
require only that a national emergency be concurrently ongo-
ing, or it could require that a reservist's service also be in
support of a particular national emergency. Given the con-
text here, I would conclude that a reservist is called to serve
“during a national emergency” only if his call comes in the
course of an operation responding to a national emergency.
Because the Court requires only that an emergency be con-
currently ongoing, I respectfully dissent.
I
A
“Tens of thousands” of federal civilian employees also
serve our Nation as military reservists. Ante, at 41.
Sometimes these individuals earn lower salaries when called
into active-duty military service than they do in their regu-
lar jobs. To mitigate this disparity, in 2009 Congress passed
the so-called “differential pay” statute, which ensures that
Page Proof Pending Publication

Cite
as: 605 U. S. 38 (2025)
57
Thomas, J., dissenting
qualifying reservists will continue to receive the amount of
their
civilian Government salaries while on active duty. See
§ 751, 123 Stat. 693–695, as amended, 5 U. S. C. § 5538. The
reservist's civilian employer is responsible for paying the dif-
ference. § 5538(c)(1).
The statute does not, however, grant a blanket authoriza-
tion for differential pay. Instead, it makes a federal civilian
employee eligible if, as relevant here, he is called to active
duty “under . . . a provision of law referred to in section
101(a)(13)(B) of title 10.” § 5538(a).
Section 101(a)(13)(B) is one part of the military's defnition
of “ `contingency operation.' ” This statute defnes a “con-
tingency operation” as “a military operation that”:
“(A) is designated by the Secretary of Defense as an
operation in which members of the armed forces are or
may become involved in military actions, operations, or
hostilities against an enemy of the United States or
against an opposing military force; or
“(B) results in the call or order to, or retention on,
active duty of members of the uniformed services under
section 688, 12301(a), 12302, 12304, 12304a, 12305, or
12406 of this title, chapter 13 of this title, section 3713
of title 14, or any other provision of law during a war or
during a national emergency declared by the President
or Congress.”
The list of cross-referenced provisions in § 101(a)(13)(B)
has evolved since Congress frst enacted this defnition in
1991, but Congress has throughout maintained a catchall for
calls to active-duty service under other provisions “during
a war or during a national emergency.” See § 631(a), 105
Stat. 1380.
B
Petitioner Nick Feliciano is an air traffc controller for the
Federal Aviation Administration (FAA) who also served as
Page Proof Pending Publication

58 FELICIANO
v. DEPARTMENT OF TRANSPORTATION
Thomas, J., dissenting
a reserve offcer for the United States Coast Guard. The
Coast
Guard called him to active-duty service for much of
the period between July 2012 and February 2017.
Pursuant to Coast Guard policy, each time it called him to
active duty, the Coast Guard provided Feliciano orders list-
ing the basis for its call. As relevant here, three of Feli-
ciano's calls specifed that he was being “called up under 10
U. S. C. 12301(d) per Executive Order 13223.” App. to Pet.
for Cert. 75a–76a; App. in No. 22–1219 (CA Fed.), p. 129.
Section 12301(d) is not one of the provisions specifcally enu-
merated in § 101(a)(13)(B). It authorizes the Government to
“order a member of a reserve component . . . to active duty,
. . . with the consent of that member.” § 12301(d).
Executive Order No. 13223, in turn, authorizes the military
to call reservists to active duty in furtherance of the national
emergency declared after the September 11 terrorist at-
tacks. 3 CFR 785 (2001 Comp.). Consistent with that di-
rective, Feliciano's § 12301(d) orders noted that he was being
called “in support of a DOD contingency operation,” while
also listing the relevant operations. App. to Pet. for Cert.
75a–76a; App. in No. 22–1219, at 129.
Feliciano did not immediately seek differential pay from
the FAA for his service under these orders. He instead
raised the issue in a 2018 appeal to the Merit Systems Pro-
tection Board (MSPB), as part of a complaint alleging that
the FAA had subjected him to a hostile work environment.
The MSPB denied Feliciano's request for differential pay.
The United States Court of Appeals for the Federal Cir-
cuit affrmed. 2023 WL 3449138, *1 (May 15, 2023). Feli-
ciano's case turned on whether he had established that his
service occurred “during a national emergency” within the
meaning of § 101(a)(13)(B). The Federal Circuit concluded
that he had not: Under Circuit precedent, Feliciano needed
to show a “connection between his service and [an] ongoing
national emergency,” id., at *2, such that he was “directly
called to serve in a contingency operation,” Adams v. De-
Page Proof Pending Publication

Cite
as: 605 U. S. 38 (2025)
59
Thomas, J., dissenting
partment of Homeland Security, 3 F. 4th 1375, 1379 (CA Fed.
2021).
But, notwithstanding the language on the face of his
orders suggesting that his service was connected to the post-
September 11 emergency, Feliciano did not “alleg[e] any con-
nection.” 2023 WL 3449138, *2. Instead, he argued only
that the Federal Circuit's precedent was wrong, and that any
active-duty service should count if there is a national emer-
gency ongoing. We granted certiorari.
II
A
This case turns on the meaning of the word “during ” in
§ 101(a)(13)(B). The parties dispute whether the phrase
“during a national emergency” covers any reservist who per-
forms active-duty service while a national emergency is on-
going, or whether it requires a connection between the serv-
ice and the emergency.
As with other common words, the meaning of “during ”
“depends on the context in and purpose for which it is used.”
Wachovia Bank, N. A. v. Schmidt, 546 U. S. 303, 318 (2006).
Sometimes, “during ” can merely “denot[e] a temporal link,”
wherein one event need only occur while another event is
ongoing. United States v. Ressam, 553 U. S. 272, 274 (2008).
Other times, however, we use “during ” in a narrower, rela-
tional sense, to reference only events that are substantively
connected to the ongoing event—that is, events that occur
“in the course of ” or “in the process of ” the ongoing event.
See 3 Oxford English Dictionary 1055 (2d ed. 1989) (emphasis
deleted); 4 id., at 1134.
Case law refects this variation. In Ressam, for example,
we held that the word “during ” was used in the broader
temporal sense in 18 U. S. C. § 844(h), which mandates a sen-
tencing enhancement for defendants who “ `carr[y] an explo-
sive during the commission of [a] felony.' ” 553 U. S., at 274–
275 (quoting § 844(h)(2)). That enhancement thus applies to
any defendant whose carrying was “contemporaneous with”
Page Proof Pending Publication

Page Proof Pending Publication
60 FELICIANO
v. DEPARTMENT OF TRANSPORTATION
Thomas, J., dissenting
his felony, even if it was not “ `in relation to' the underlying
felony
.” Id., at 273–275.
Conversely, courts in other contexts have held that the
word “during ” contains a relational component. For in-
stance, several Circuits have recognized this component in
the Sentencing Guidelines' defnition of “relevant conduct,”
which encompasses all actions by the defendant “that oc-
curred during the commission of the offense of conviction.”
United States Sentencing Commission, Guidelines Manual
§ 1B1.3(a)(1) (Nov. 2024); see, e. g., United States v. Caldwell,
128 F. 4th 1170, 1180–1183 (CA10 2025) (collecting cases, and
distinguishing Ressam). “[W]hen defning `relevant con-
duct,' ” they have explained, “the term `during ' conveys a
linkage that is more than a mere temporal overlap; it also
conveys a qualitative overlap such that the conduct must be
related or connected to the crime of conviction.” United
States v. Agyekum, 846 F. 3d 744, 751 (CA4 2017).
Title 10 also refects this variation. The Government has
suggested that the similar phrase “[i]n time of national emer-
gency” in § 12302 “speaks only temporally.” Ante, at 46–47
(citing Tr. of Oral Arg. 61–62). But, other provisions in Title
10 appear to speak in relational terms. For example, as the
majority acknowledges, when Congress defned “ `captured
record' ” to mean certain “material captured during combat
operations,” it presumably was describing only material cap-
tured in the course of those combat operations. § 427(g)(1);
see ante, at 50.
The upshot is that the word “during ” does not have a sin-
gle defnition on which to hang our analysis. Instead, to de-
termine its meaning here, we must read the § 101(a)(13)(B)
catchall “in [its] context and with a view to [its] place in
the overall statutory scheme.” Davis v. Michigan Dept. of
Treasury, 489 U. S. 803, 809 (1989).
B
The context of § 101(a)(13)(B) makes clear that active-duty
service occurs “during a national emergency” within the

Cite
as: 605 U. S. 38 (2025)
61
Thomas, J., dissenting
meaning of that provision only if the service occurs in the
course
of a national emergency. In other words, the reserv-
ist must be called to serve in an operation responding to a
national emergency. Several important textual clues coun-
sel in favor of this reading.
1
To start, the scope of the phrase “during a national emer-
gency” is limited by § 101(a)(13)(B)'s location within Con-
gress's defnition of “contingency operation.” Because “an
entirely artifcial defnition is rare,” we typically expect the
meaning of a defnition to be “closely related to the ordinary
meaning of the word being defned.” A. Scalia & B. Garner,
Reading Law 228 (2012) (Scalia & Garner). Thus, the “ordi-
nary meaning of a defned term” often “plays a . . . limit-
ing role” when choosing between possible interpretations.
Bond v. United States, 572 U. S. 844, 861–862 (2014).
This canon applies with full force here. As a matter of
ordinary meaning, the term “contingency operation” in Title
10 refers to the subset of military operations that relates
to a particular contingency. We should therefore expect
§ 101(a)(13) to cover only operations that are part of the mili-
tary's response to “emergency” situations or otherwise ne-
cessitated by “required military operations.” Dept. of De-
fense Dictionary of Military and Associated Terms 86 (JCS
Pub. 1–02 1989). Otherwise, there would be no reason for
Congress to use “contingency” as a modifying adjective. See
Weyerhaeuser Co. v. United States Fish and Wildlife Serv.,
586 U. S. 9, 19 (2018) (“Adjectives modify nouns—they pick
out a subset of a category that possesses a certain quality”).
The other categor ies of “conti ngency operati ons” i n
§ 101(a)(13) confor m to th is underst andi ng. Sec ti on
101(a)(13)(A) covers a paradigmatic kind of contingency op-
eration—those wherein members of the military are likely to
be engaged in opposition to “an enemy of the United States
or against an opposing military force.” Several of the enu-
merated provisions in § 101(a)(13)(B) similarly cover opera-
tions directly responding to specifc exigent situations. See,
Page Proof Pending Publication

62 FELICIANO
v. DEPARTMENT OF TRANSPORTATION
Thomas, J., dissenting
e. g., § 12304a (“assistance in response to a major disaster or
emergency”);
§ 12406 (“invasion” or “rebellion”). And, al-
though the remaining cross-referenced provisions are not
pegged to specifc exigencies, they too sound in exigency,
each signaling some reason why a reservist is called to active
duty. See, e. g., §§ 12301(a), 12302, 12304.
Because the common thread among these categories is that
they contemplate only exigent military operations, it follows
that the same should be true of the “during a national emer-
gency” catchall. We ordinarily read catchall “clauses . . . as
bringing within a statute categories similar in type to those
specifcally enumerated.” Federal Maritime Comm'n v.
Seatrain Lines, Inc., 411 U. S. 726, 734 (1973). The catch-
all here should not be read in a way that eviscerates
§ 101(a)(13)'s “contingency” focus.
Tellingly, the military itself has understood the term “con-
tingency operation” to have a fnite scope. Notwithstanding
the existence of ongoing national emergencies, it has for
some troop activations issued “orders stat[ing] that they are
`non-contingency' activation orders.” Adams, 3 F. 4th, at
1377. For example, like Feliciano, the plaintiff in Adams
consented to “ `voluntary active duty under [§ ]12301(d),' ”
but his orders stated that he was being activated in a “ `non-
contingency' ” capacity. Id., at 1377, 1380.
It follows that the phrase “during a national emergency”
cannot be understood in purely temporal terms. A purely
temporal construction would eviscerate the specifcation of
“contingency operation”: If all military operations that occur
concurrent with a national emergency are contingency oper-
ations, then any military operation requiring a call to active-
duty service could be a contingency operation, regardless of
whether there is any contingency involved. Such a capa-
cious reading would implausibly divorce the term from its
ordinary meaning.
A review of the other provisions in Title 10 that use the
term “contingency operation” confrms this implausibility.
Because § 101(a)(13) is a defnition that “appl[ies throughout]
Page Proof Pending Publication

Cite
as: 605 U. S. 38 (2025)
63
Thomas, J., dissenting
this title,” see § 101, as well as in other provisions where it is
i
ncorporated by reference, its defnition must ft the broader
statutory scheme, Ali v. Federal Bureau of Prisons, 552
U. S. 214, 222 (2008). There are “dozens of provisions inside
and outside Title 10 that are applicable to” contingency oper-
ations, and a broad reading of that term would lead to untold
consequences. Brief for Respondent 22. For example, for
contracting provisions such as § 2662(f )(1)(E)—where Con-
gress created a reporting requirement but provided an ex-
ception for contingency operations—a purely temporal in-
terpretation of “contingency operation” would invite the
exception to swallow the rule. Likewise, such an interpre-
tation would mean that—under a provision applying the Uni-
form Code of Military Justice to civilians who accompany
the U. S. military in the feld “[i]n time of declared war or
a contingency operation”—the availability of civilian court-
martial could be quite open-ended. § 802(a)(10); see United
States v. Ali, 71 M. J. 256, 261–262 (C. A. Armed Forces 2012).
That possibility would run up against our normal under-
standing of court-martial as a “narrow exception” to the
civilian justice system, and exacerbate any constitutional
infrmities of this provision. Reid v. Covert, 354 U. S. 1,
21, 31–33 (1957) (plurality opinion). This implausibility is
“strong evidence” that the term “contingency operation”
must retain limiting force. Yegiazaryan v. Smagin, 599
U. S. 533, 548 (2023).
2
The need for “contingency operation” to retain limiting
force is particularly apparent because Congress enacted
§ 101(a)(13)(B) against a backdrop of indefnite and continual
national emergencies. With the exception of a 1-year inter-
regnum from 1978 to 1979, the United States has had at least
one national emergency in effect at all times since 1933.
1
1
Congress took note of this problem in the 1970s. S. Rep. No. 93–549,
p. III (1973). It passed the National Emergencies Act in 1976, which or-
dered that the then-existing emergencies be terminated as of 1978.
§ 101(a), 90 Stat. 1255 (codifed at 50 U. S. C. § 1601(a)). But, the President
Page Proof Pending Publication

64 FELICIANO
v. DEPARTMENT OF TRANSPORTATION
Thomas, J., dissenting
Thus, when Congress passed § 101(a)(13)(B) in 1991, it would
have
expected that some national emergency or other would
generally be in effect. It strains credulity to think that
Congress could have meant “contingency operation” to mean,
as a practical matter, essentially every military operation.
2
To the extent there could be any doubt, the structure of
§ 101(a)(13)(B) confrms that Congress did not intend for
the “during a national emergency” catchall to be all encom-
passing. After all, Congress created that provision as a
catchall to a long list of enumerated provisions. As origi-
nally enacted, § 101(a)(13)(B) specifed that a “military opera-
tion” would qualify as a “ `contingency operation' ” if it “re-
sults in the call or order to, or retention on, active duty” of
troops pursuant to one of seven enumerated provisions, one
enumerated chapter of provisions, or “any other provision of
law during a war or during a national emergency.” 105
Stat. 1380. Congress has maintained this structure since
then. The only changes it has made have been to enumerate
additional statutes. See § 101(a)(13)(B).
Congress's focus on a reservist's “call or order” to active
duty and whether that “call or order” arises under specifc
provisions of law suggests that Congress cared about the
soon proclaimed a new emergency to order sanctions against Iran. Exec.
Order No. 12170, 3 CFR 457 (1979 Comp.). That emergency remains in
effect to this day, alongside several dozen other emergencies since desig-
nated. 89 Fed. Reg. 87761 (2024).
2
Reading the term “contingency operation” to cover all military opera-
tions that occur while a national emergency is also ongoing would appear
particularly incongruent given the nonmilitary nature of many emergen-
cies. In the years leading up to the 1991 enactment of 10 U. S. C.
§ 101(a)(13), almost all the emergency proclamations in effect concerned
economic sanctions. See Brennan Center for Justice, Declared National
Emergencies Under the National Emergencies Act (last updated Apr. 7,
2025), https:// brennancenter.org/our-work/research-reports/declared-
national-emergencies-under-national-emergencies-act. It is not apparent
why the existence of unrelated sanctions, administered by nonmilitary of-
fcials, would transform routine military operations into contingency oper-
ations as a matter of ordinary understanding.
Page Proof Pending Publication

Cite
as: 605 U. S. 38 (2025)
65
Thomas, J., dissenting
contents of and the basis for a reservist's activation orders.
If
Congress had meant to effectively deem all operations re-
quiring calls to active-duty service as occurring “during a
national emergency,” then its list of enumerated provisions
would have been unnecessary. Because some emergency is
invariably ongoing, Congress could have omitted all those
enumerations without any meaningful difference.
The superfuity involved in a purely temporal reading is a
strong sign that a military operation occurs “during a na-
tional emergency” only if it occurs in the course of the Gov-
ernment's response to a national emergency. Because we
interpret statutes, where possible, to avoid superfuity, we
strive to avoid interpretations that “would in practical effect
render [statutory language] entirely superfuous in all but
the most unusual circumstances.” TRW Inc. v. Andrews,
534 U. S. 19, 29 (2001). We likewise strive to avoid “un-
bounded interpretation[s]” of a catchall that would “render
superfuous” Congress's provision of “a reticulated list” else-
where in the statute. Fischer v. United States, 603 U. S.
480, 493 (2024). Reading “during a national emergency” in
§ 101(a)(13)(B) to reach only operations undertaken in the
course of the national emergency would avoid these disfa-
vored interpretive outcomes.
3
The postenactment history of both § 101(a)(13)(B) and the
differential-pay statute that incorporates that provision fur-
ther counsel in favor of reading “during a national emer-
gency” narrowly. It is well established that “subsequent
acts can shape or focus” our selection between possible statu-
tory meanings. FDA v. Brown & Williamson Tobacco
Corp., 529 U. S. 120, 143 (2000). And, in particular, we must
read “a change in [statutory] language . . . , if possible, to
have some effect.” American Nat. Red Cross v. S. G., 505
U. S. 247, 263 (1992). But here, Congress's postenactment
amendments would be superfuous if all military operations
Page Proof Pending Publication

66 FELICIANO
v. DEPARTMENT OF TRANSPORTATION
Thomas, J., dissenting
were already contingency operations through the “during a
nati
onal emergency” catchall.
Most notably, Congress in 2013 amended § 101(a)(13)(B) to
specify that military operations requiring troop activations
under what is now 14 U. S. C. § 3713—a provision allowing
for the emergency activation of Coast Guard reservists in
certain circumstances—would henceforth qualify as contin-
gency operations. § 681(a), 126 Stat. 1795. Congress also
specifed that this amendment would be “retroactive” for one
year for purposes of differential pay. § 681(d)(2)(A), id., at
1796. But, if the phrase “during a national emergency”
makes all military operations contingency operations while a
national emergency is in effect, then this amendment and its
retroactivity provision would have been wholly superfuous.
With emergencies always in effect, including for the entirety
of the 1-year retroactivity period, reservists activated pursu-
ant to the Coast Guard provision would already have been
participants in contingency operations and so entitled to dif-
ferential pay.
Other congressional amendments refect the same prob-
lem. In 2011, Congress amended § 101(a)(13)(B) to deem as
contingency operations military operations requiring activa-
tions through § 12304a, which allows certain reservists to be
called to active duty “[w]hen a Governor requests Federal
assistance in responding to a major disaster or emergency.”
§ 515(a), 125 Stat. 1394. And, in 2018, Congress amended
the differential-pay statute to entitle reservists activated
under 10 U. S. C. § 12304b to differential pay. § 605, 132
Stat. 1795. That provision allows activations for “pre-
planned mission[s] in support of a combatant command.”
§ 12304b(a). But, given the backdrop of constant national
emergencies, these changes could have little, if any, practical
effect if § 101(a)(13)(B) already made all military operations
contingency operations so long as an emergency is ongoing.
Because we disfavor statutory interpretations that would
render statutory language all but superfuous “in practical
Page Proof Pending Publication

Cite
as: 605 U. S. 38 (2025)
67
Thomas, J., dissenting
effect,” it makes little sense to conclude that Congress
enac
ted these amendments in case of a hypothetical day
without emergencies. TRW, 534 U. S., at 29. This statu-
tory history therefore provides another reason to adopt a
cabined reading of the “during a national emergency”
language.
***
Taken together, these contextual clues establish that the
“during a national emergency” catchall in § 101(a)(13)(B)
reaches only military operations conducted in response to a
national emergency. The differential-pay statute, in cover-
ing any reservist who is called to active duty “pursuant to a
call or order” under “a provision of law referred to in section
101(a)(13)(B), ” i ncor porates § 101(a)(13)(B)'s li mits. 5
U. S. C. § 5538(a). Thus, the statutory context of 10 U. S. C.
§ 101(a)(13)(B) also establishes that a reservist qualifies for
differential pay under the “catchall” only if he is called to
serve in an operation responding to a national emergency.
Reservists cannot benefit if they are called to serve merely
while other, unrelated emergency responses are ongoing.
III
The majority does not persuasively grapple with the fore-
going evidence of § 101(a)(13)(B)'s meaning. At most, its
reasoning suggests that Congress could have spoken more
clearly. But, that conclusion cannot justify the Court's deci-
sion today.
As an initial matter, the majority wrongly puts a thumb
on the scale in favor of reading the word “during ” in a purely
temporal sense. “Normally,” it says, “that word `denotes a
temporal link' and means `contemporaneous with.' ” Ante, at
44 (quoting Ressam, 553 U. S., at 274–275). But, as the major-
ity later acknowledges, the meaning of “during ” is context
dependent. Ante, at 49–50; supra, at 59–60. Often, “ordi-
nary reader[s]” will read “during ” to “require both a tempo-
ral and substantive connection.” Ante, at 50. Our decision
Page Proof Pending Publication

68 FELICIANO
v. DEPARTMENT OF TRANSPORTATION
Thomas, J., dissenting
in Ressam is not to the contrary: It stated only that the
purely
temporal sense was “the most natural reading of the
word as used in the statute” at issue. 553 U. S., at 274–275
(emphasis added).
Even if the majority were right about “during ” as a gen-
eral matter, we still must read statutes in context. See
Home Depot U. S. A., Inc. v. Jackson, 587 U. S. 435, 441
(2019) (narrowly reading a term that, “standing alone, is
broad”). Here, the majority too quickly brushes aside the
key contextual clues in the scheme before us.
To start, the majority cannot disregard the ordinary mean-
ing of “contingency operation” on the ground that we are
interpreting an “express statutory defnition” of that term.
Ante, at 50–51, n. 4. When the meaning of a statutory def-
nition is unclear, “the ordinary meaning of the term . . . is
one of `the most important' factors we can consider.” Delli-
gatti v. United States, 604 U. S. 423, 438 (2025) (quoting
Scalia & Garner 228); see supra, at 61. And, even on the
majority's view, the meaning of § 101(a)(13)(B) is at least de-
batable: The majority acknowledges the “force” of counter-
vailing arguments, and it all but admits that its reading gen-
erates superfuity, at least as to Congress's retroactive
provision of differential pay under the Coast Guard amend-
ment. Ante, at 49, 53–54, n. 5.
The majority cannot dodge the larger superfuity problem
raised by its overbroad reading either. The majority specu-
lates that there could be a day where no national emergen-
cies are in effect. Ante, at 52–53. But, given the fve-plus
decades of national emergencies against which Congress leg-
islated, that possibility is far too remote to refect Congress's
likely intention in enacting § 101(a)(13)(B). And, Congress's
postenactment amendments—including the retroactive
amendment—only further confrm that it intended all of
§ 101(a)(13)(B) to have present effect.
The majority downplays the ripple effects its opinion will
have for the term “contingency operation” as used in other
Page Proof Pending Publication

Cite
as: 605 U. S. 38 (2025)
69
Thomas, J., dissenting
provisions. Notwithstanding its decision to defne “contin-
gency
operation” to mean essentially “any military opera-
tion,” the majority offers “no views” on the full consequences
of its interpretation. Ante, at 55, n. 6. But, Congress made
§ 101(a)(13) the defi niti on for “conti ngency operati on”
throughout Chapter 10 and beyond, and so we “must, to the
extent possible, ensure that the statutory scheme is coherent
and consistent.” Ali, 552 U. S., at 222. We cannot leave
that obligation for another day.
The majority's competing textual arguments are also un-
availing. The majority invokes the presumption of consist-
ent usage and the canon of meaningful variation to argue
that a comparison with other statutes shows that “during ”
in § 101(a)(13)(B) is merely temporal. Under these princi-
ples, “[i]n a given statute, the same term usually has the
same meaning and different terms usually have different
meanings.” Pulsifer v. United States, 601 U. S. 124, 149
(2024). Thus, the majority argues, it is noteworthy that
Congress used only the word “during,” given that other
Code provisions use “during ” or equivalent language in a
purely temporal sense. Ante, at 53. If Congress had
wanted to reach only active-duty service undertaken in the
course of a national emergency, the majority posits, it would
have borrowed different, clearer language, such as “during
and in relation to.” Ante, at 46. These arguments are true
as far as they go, but they go only so far.
Because “drafters more than rarely use the same word to
denote different concepts, and often . . . use different words
to denote the same concept,” inferences like the majority's
are “particularly defeasible by context.” Scalia & Garner
170–171. And, the presumption of consistent usage and
canon of meaningful variation carry especially little weight
when applied to words that are “ubiquitous” and “context-
dependent,” whose use drafters are not “likely to keep track
of and standardize.” Pulsifer, 601 U. S., at 149. That is the
case with a preposition such as “during,” which even the ma-
Page Proof Pending Publication

70 FELICIANO
v. DEPARTMENT OF TRANSPORTATION
Thomas, J., dissenting
jority acknowledges to be context dependent, including in its
meani
ng elsewhere in Title 10. See ante, at 50; supra, at
60. Thus, the majority's arguments on this front cannot be
controlling.
3
Likewise, the interaction of the differential-pay statute
with 18 U. S. C. § 209 does not move the needle. That stat-
ute criminally bars private parties from supplementing a
federal employee's salary, but it creates an exception for par-
ties who give differential pay to reservists serving on “active
duty under a provision of law referred to in section
101(a)(13).” §§ 209(a), (h). The majority warns that a nar-
row reading of 10 U. S. C. § 101(a)(13) could create liability
for private employers who mistakenly believe an employee
to be serving in the course of a national emergency. Ante,
at 47–48. But, even setting aside that such employers would
likely have a mens rea defense, see ante, at 48, n. 3, this
argument for lenity can be relevant only if, “at the end of
the process of construing what Congress has expressed[,] . . .
the ordinary canons of statutory construction have revealed
no satisfactory construction,” Lockhart v. United States, 577
U. S. 347, 361 (2016) (internal quotation marks omitted).
Here, those ordinary canons supply an answer.
No more availing is the majority's invocation of the
Congressional Budget Offce (CBO) as evidence of what
an “ordinary reader” might think. Ante, at 48. The major-
ity highlights that CBO at one point applied the majority's
reading when estimating the cost of “potential legislation
featuring [similar] terms.” Ibid. But, as the majority ac-
3
The majority emphasizes the Government's concession that § 12302, one
of the provisions enumerated in § 101(a)(13)(B), “speaks only temporally”
when “authoriz[ing] the activation of various reservists `[i]n time of na-
tional emergency.' ” Ante, at 46–47; see supra, at 60. Whatever the mer-
its of that concession, it does not help the majority. Even when read purely
temporally, § 12302—which allows the Government to maintain “[i]n time
of national emergency” a limited “Ready Reserve” of troops who can be
activated as needed—has a clear exigency focus. It does not support the
majority's near-boundless interpretation of the § 101(a)(13)(B) catchall.
Page Proof Pending Publication

Cite
as: 605 U. S. 38 (2025)
71
Thomas, J., dissenting
knowledges, “no one votes for CBO reports,” and courts owe
CBO
“no rote deference.” Ibid. It is not apparent, then,
why CBO's reports are relevant—particularly given that the
reports contain no interpretive analysis.
4
That one general-
ist agency, for unknown reasons, once shared the majority's
view is hardly compelling evidence of § 101(a)(13)(B)'s mean-
ing, especially given the weight of the interpretive clues and
the practice of the military itself. See supra, at 61–62.
Finally, the majority cannot fall back on workability con-
cerns. The majority asks how a substantive standard can
be discerned from the “during a national emergency” lan-
guage, pointing to the somewhat different formulations that
the Government and I have used compared to the Federal
Circuit's. Ante, at 47, 49. But, “[i]t is not our place to
question whether Congress adopted the . . . most workable
policy, only to discern and apply the policy it did adopt.”
Ysleta del Sur Pueblo v. Texas, 596 U. S. 685, 706 (2022).
In any event, the majority's concerns are unjustifed.
However formulated, the inquiry should ordinarily be
straightforward. A reservist is eligible for differential pay
through the “during a national emergency” catchall if he is
called to active-duty service in an operation responding to
such an emergency. The nature of an activation can ordi-
narily be determined from the face of the reservist's activa-
tion orders, which, under Department of Defense and Coast
Guard policies, must state whether he is being activated in
support of a contingency operation. Brief for Respondent
23–24; see Adams, 3 F. 4th, at 1379. If there is any ambigu-
ity, the reservist or his civilian employer can obtain clarif-
cation. Offce of Personnel Management, OPM Policy Guid-
ance Regarding Reservist Differential Under 5 U. S. C. 5538,
p. 23 (rev. June 23, 2015), https://www.opm.gov/policy-
4
For the reports, see CBO, Cost Estimate, S. 593: Reservist Pay Secu-
rity Act of 2004, pp. 2–3 (Aug. 4, 2004); CBO, Cost Estimate, S. 2400:
Ronald W. Reagan National Defense Authorization Act for Fiscal Year
2005, p. 9 (July 21, 2004).
Page Proof Pending Publication

72 FELICIANO
v. DEPARTMENT OF TRANSPORTATION
Thomas, J., dissenting
data-oversight/pay-leave/pay-administration/reservist-
di
fferential/policyguidance.pdf. The majority has no basis
to deviate from the commands of statutory text.
***
My interpretive conclusion does not mean that Feliciano
should be denied differential pay. As even the Government
admits, Feliciano's “orders indicate that [he] would have been
entitled to differential pay” under a proper reading of
§ 101(a)(13)(B) because they indicate that he was being called
to active duty to support the Coast Guard's response to a
national emergency. Brief for Respondent 36; see supra, at
58. The Government argues, however, that petitioner has
forfeited any entitlement. Because we are not a court of
frst view, I would vacate and remand so that the Federal
Circuit may assess these issues in the frst instance. The
majority instead grants Feliciano relief based on a misread-
ing of the statute. I respectfully dissent.
Page Proof Pending Publication

Page Proof Pending Publication
Reporter’s Note
The attached opinion has been revised to refect the usual publication
and citation style of the United States Reports. The revised pagination
makes available the offcial United States Reports citation in advance of
publication. The syllabus has been prepared by the Reporter of Decisions
for the convenience of the reader and constitutes no part of the opinion of
the Court. A list of counsel who argued or fled briefs in this case, and
who were members of the bar of this Court at the time this case was
argued, has been inserted following the syllabus. Other revisions may
include adjustments to formatting, captions, citation form, and any errant
punctuation. The following additional edits were made:
None