BARNHART, COMMISSIONER OF SOCIAL SECURITY v. THOMAS

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Syllabus
BARNHART, COMMISSIONER OF SOCIAL SECURITY
v. THOMAS
certiorari to the united states court of appeals for
the third circuit
No. 02–763. Argued October 14, 2003—Decided November 12, 2003
A person is disabled, and thereby eligible for Social Security disability
insurance benefits and Supplemental Security Income (SSI), “only if his
physical or mental impairment or impairments are of such severity that
he is not only unable to do his previous work but cannot, considering
his age, education, and work experience, engage in any other kind of
substantial gainful work which exists in the national economy.” 42
U. S. C. §§ 423(d)(2)(A), 1382c(a)(3)(B) (emphasis added) (hereinafter
§ 423(d)(2)(A)). After her job as an elevator operator was eliminated,
respondent Thomas applied for disability insurance benefits and SSI.
An Administrative Law Judge (ALJ) found that her impairments did
not prevent her from performing her past relevant work as an elevator
operator, rejecting her argument that she is unable to do that work
because it no longer exists in significant numbers in the national econ-
omy. The District Court affirmed the ALJ, concluding that whether
Thomas’s old job exists is irrelevant under the Social Security Adminis-
tration’s (SSA) regulations. In reversing and remanding, the en banc
Third Circuit held that § 423(d)(2)(A) unambiguously provides that the
ability to perform prior work disqualifies from benefits only if it is sub-
stantial gainful work which exists in the national economy.
Held: The SSA’s determination that it can find a claimant not disabled
where she remains physically and mentally able to do her previous
work, without investigating whether that work exists in significant
numbers in the national economy, is a reasonable interpretation of
§ 423(d)(2)(A) that is entitled to deference under Chevron U. S. A. Inc.
v. Natural Resources Defense Council, Inc., 467 U. S. 837. Section
423(d)(2)(A) establishes two requirements: An impairment must render
an individual “unable to do his previous work” and must also preclude
him from “engag[ing] in any other kind of substantial gainful work.”
The clause “which exists in the national economy” clearly qualifies the
latter requirement. The issue in this case is whether that clause also
qualifies the former requirement. The SSA’s regulations, which create
a five-step sequential evaluation process to determine disability, answer
that question in the negative. At step four, the SSA will find not
disabled a claimant who can do his previous work, without inquiring

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whether that work exists in the national economy. Rather, it reserves
inquiry into the national economy for the fifth step, when it considers
vocational factors and determines whether the claimant can perform
other jobs in the national economy. See 20 CFR §§ 404.1520(f ),
404.1560(c), 416.920(f), 416.960(c). That interpretation is a reasonable
construction of § 423(d)(2)(A). The Third Circuit’s contrary reading ig-
nores the grammatical “rule of the last antecedent,” under which a limit-
ing clause or phrase should be read to modify only the noun or phrase
that it immediately follows. Construing § 423(d)(2)(A) in accord with
this rule is quite sensible. Congress could have determined that an
analysis of a claimant’s capacity to do his previous work would in most
cases be an effective and efficient administrative proxy for the claimant’s
ability to do some work that exists in the national economy. There
is good reason to use such a proxy to avoid the more expansive and
individualized step-five analysis. The proper Chevron inquiry is not
whether an agency construction can give rise to undesirable results in
some instances (which both the SSA’s and the Third Circuit’s construc-
tions can), but whether, in light of the alternatives, the agency construc-
tion is reasonable. Here, the SSA’s authoritative interpretation satis-
fies that test. Pp. 23–30.
294 F. 3d 568, reversed.
Scalia, J., delivered the opinion for a unanimous Court.
Jeffrey A. Lamken argued the cause for petitioner. With
him on the briefs were Solicitor General Olson, Assistant
Attorney General McCallum, Deputy Solicitor General
Kneedler, William Kanter, Wendy M. Keats, and Barbara
L. Spivak.
Abraham S. Alter argued the cause and filed a brief for
respondent.
Justice Scalia delivered the opinion of the Court.
Under the Social Security Act, the Social Security Admin-
istration (SSA) is authorized to pay disability insurance ben-
efits and Supplemental Security Income to persons who have
a “disability.” A person qualifies as disabled, and thereby
eligible for such benefits, “only if his physical or mental im-
pairment or impairments are of such severity that he is not
only unable to do his previous work but cannot, considering

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his age, education, and work experience, engage in any other
kind of substantial gainful work which exists in the national
economy.” 42 U. S. C. §§ 423(d)(2)(A), 1382c(a)(3)(B). The
issue we must decide is whether the SSA may determine
that a claimant is not disabled because she remains physi-
cally and mentally able to do her previous work, without
investigating whether that previous work exists in signifi-
cant numbers in the national economy.
I
Pauline Thomas worked as an elevator operator for six
years until her job was eliminated in August 1995. In June
1996, at age 53, Thomas applied for disability insurance bene-
fits under Title II and Supplemental Security Income under
Title XVI of the Social Security Act. See 49 Stat. 622,
as amended, 42 U. S. C. § 401 et seq. (Title II); as added, 86
Stat. 1465, and as amended, § 1381 et seq. (Title XVI). She
claimed that she suffered from, and was disabled by, heart
disease and cervical and lumbar radiculopathy.
After the SSA denied Thomas’s application initially and on
reconsideration, she requested a hearing before an Adminis-
trative Law Judge (ALJ). The ALJ found that Thomas had
“hypertension, cardiac arrythmia, [and] cervical and lumbar
strain/sprain.” Decision of ALJ 5, Record 15. He con-
cluded, however, that Thomas was not under a “disability”
because her “impairments do not prevent [her] from per-
forming her past relevant work as an elevator operator.”
Id., at 6, Record 16. He rejected Thomas’s argument that
she is unable to do her previous work because that work no
longer exists in significant numbers in the national economy.
The SSA’s Appeals Council denied Thomas’s request for
review.
Thomas then challenged the ALJ’s ruling in the United
States District Court for the District of New Jersey, renew-
ing her argument that she is unable to do her previous work
due to its scarcity. The District Court affirmed the ALJ,

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concluding that whether Thomas’s old job exists is irrele-
vant under the SSA’s regulations. Thomas v. Apfel, Civ.
No. 99–2234 (Aug. 17, 2000). The Court of Appeals for
the Third Circuit, sitting en banc, reversed and remanded.
Over the dissent of three of its members, it held that the
statute unambiguously provides that the ability to perform
prior work disqualifies from benefits only if it is “substantial
gainful work which exists in the national economy.” 294
F. 3d 568, 572 (2002). That holding conflicts with the deci-
sions of four other Courts of Appeals. See Quang Van Han
v. Bowen, 882 F. 2d 1453, 1457 (CA9 1989); Garcia v. Secre-
tary of Health and Human Services, 46 F. 3d 552, 558 (CA6
1995); Pass v. Chater, 65 F. 3d 1200, 1206–1207 (CA4 1995);
Rater v. Chater, 73 F. 3d 796, 799 (CA8 1996). We granted
the SSA’s petition for certiorari. 537 U. S. 1187 (2003).
II
As relevant to the present case, Title II of the Act defines
“disability” as the “inability to engage in any substantial
gainful activity by reason of any medically determinable
physical or mental impairment which can be expected to re-
sult in death or which has lasted or can be expected to last
for a continuous period of not less than 12 months.” 42
U. S. C. § 423(d)(1)(A). That definition is qualified, however,
as follows:
“An individual shall be determined to be under a dis-
ability only if his physical or mental impairment or im-
pairments are of such severity that he is not only un-
able to do his previous work but cannot, considering his
age, education, and work experience, engage in any
other kind of substantial gainful work which exists in
the national economy. . . .” § 423(d)(2)(A) (emphases
added).
“[W]ork which exists in the national economy” is defined to
mean “work which exists in significant numbers either in the

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region where such individual lives or in several regions of
the country.” Ibid. Title XVI of the Act, which governs
Supplemental Security Income for disabled indigent per-
sons, employs the same definition of “disability” used in Title
II, including a qualification that is verbatim the same as
§ 423(d)(2)(A). See 42 U. S. C. § 1382c(a)(3)(B). For simplic-
ity’s sake, we will refer only to the Title II provisions, but
our analysis applies equally to Title XVI.
Section 423(d)(2)(A) establishes two requirements for dis-
ability. First, an individual’s physical or mental impairment
must render him “unable to do his previous work.” Second,
the impairment must also preclude him from “engag[ing] in
any other kind of substantial gainful work.” The parties
agree that the latter requirement is qualified by the clause
that immediately follows it—“which exists in the national
economy.” The issue in this case is whether that clause also
qualifies “previous work.”
The SSA has answered this question in the negative.
Acting pursuant to its statutory rulemaking authority, 42
U. S. C. §§ 405(a) (Title II), 1383(d)(1) (Title XVI), the agency
has promulgated regulations establishing a five-step sequen-
tial evaluation process to determine disability. See 20 CFR
§ 404.1520 (2003) (governing claims for disability insurance
benefits); § 416.920 (parallel regulation governing claims for
Supplemental Security Income). If at any step a finding of
disability or nondisability can be made, the SSA will not re-
view the claim further. At the first step, the agency will
find nondisability unless the claimant shows that he is not
working at a “substantial gainful activity.” §§ 404.1520(b),
416.920(b). At step two, the SSA will find nondisability un-
less the claimant shows that he has a “severe impairment,”
defined as “any impairment or combination of impairments
which significantly limits [the claimant’s] physical or men-
tal ability to do basic work activities.” §§ 404.1520(c),
416.920(c). At step three, the agency determines whether
the impairment which enabled the claimant to survive step

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two is on the list of impairments presumed severe enough
to render one disabled; if so, the claimant qualifies.
§§ 404.1520(d), 416.920(d). If the claimant’s impairment is
not on the list, the inquiry proceeds to step four, at which
the SSA assesses whether the claimant can do his previous
work; unless he shows that he cannot, he is determined not
to be disabled.1 If the claimant survives the fourth stage,
the fifth, and final, step requires the SSA to consider so-
called “vocational factors” (the claimant’s age, education, and
past work experience), and to determine whether the claim-
ant is capable of performing other jobs existing in sig-
nificant numbers in the national economy. §§ 404.1520(f),
404.1560(c), 416.920(f), 416.960(c).2
As the above description shows, step four can result in a
determination of no disability without inquiry into whether
the claimant’s previous work exists in the national economy;
the regulations explicitly reserve inquiry into the national
economy for step five. Thus, the SSA has made it perfectly
clear that it does not interpret the clause “which exists in the
national economy” in § 423(d)(2)(A) as applying to “previous
work.” 3 The issue presented is whether this agency inter-
pretation must be accorded deference.
1 The step-four instructions to the claimant read as follows: “If we can-
not make a decision based on your current work activity or on medical
facts alone, and you have a severe impairment(s), we then review your
residual functional capacity and the physical and mental demands of the
work you have done in the past. If you can still do this kind of work, we
will find that you are not disabled.” 20 CFR §§ 404.1520(e), 416.920(e)
(2003).
2 In regulations that became effective on September 25, 2003, the SSA
amended certain aspects of the five-step process in ways not material to
this opinion. The provisions referred to as subsections (e) and (f) in this
opinion are now subsections (f) and (g).
3 This interpretation was embodied in the regulations that first estab-
lished the five-step process in 1978, see 43 Fed. Reg. 55349 (codified, as
amended, at 20 CFR §§ 404.1520 and 416.920 (1982)). Even before enact-
ment of § 423(d)(2)(A) as part of the Social Security Amendments of 1967,
the SSA disallowed disability benefits when the inability to work was

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As we held in Chevron U. S. A. Inc. v. Natural Resources
Defense Council, Inc., 467 U. S. 837, 843 (1984), when a stat-
ute speaks clearly to the issue at hand we “must give effect
to the unambiguously expressed intent of Congress,” but
when the statute “is silent or ambiguous” we must defer to
a reasonable construction by the agency charged with its im-
plementation. The Third Circuit held that, by referring
first to “previous work” and then to “any other kind of sub-
stantial gainful work which exists in the national economy,”
42 U. S. C. § 423(d)(2)(A) (emphasis added), the statute unam-
biguously indicates that the former is a species of the latter.
“When,” it said, “a sentence sets out one or more specific
items followed by ‘any other’ and a description, the specific
items must fall within the description.” 294 F. 3d, at 572.
We disagree. For the reasons discussed below, the interpre-
tation adopted by SSA is at least a reasonable construction
of the text and must therefore be given effect.
The Third Circuit’s reading disregards—indeed, is pre-
cisely contrary to—the grammatical “rule of the last anteced-
ent,” according to which a limiting clause or phrase (here,
the relative clause “which exists in the national economy”)
should ordinarily be read as modifying only the noun or
phrase that it immediately follows (here, “any other kind of
substantial gainful work”). See 2A N. Singer, Sutherland
on Statutory Construction § 47.33, p. 369 (6th rev. ed. 2000)
(“Referential and qualifying words and phrases, where no
contrary intention appears, refer solely to the last anteced-
ent”). While this rule is not an absolute and can assuredly
be overcome by other indicia of meaning, we have said that
construing a statute in accord with the rule is “quite sensible
as a matter of grammar.” Nobelman v. American Savings
Bank, 508 U. S. 324, 330 (1993). In FTC v. Mandel Broth-
ers, Inc., 359 U. S. 385 (1959), this Court employed the rule
to interpret a statute strikingly similar in structure to
caused by “technological changes in the industry in which [the claimant]
has worked.” 20 CFR § 404.1502(b) (1961).

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§ 423(d)(2)(A)—a provision of the Fur Products Labeling Act,
15 U. S. C. § 69, which defined “ ‘invoice’ ” as “ ‘a written ac-
count, memorandum, list, or catalog . . . transported or deliv-
ered to a purchaser, consignee, factor, bailee, correspondent,
or agent, or any other person who is engaged in dealing
commercially in fur products or furs.’ ” 359 U. S., at 386
(quoting 15 U. S. C. § 69(f)) (emphasis added). Like the
Third Circuit here, the Court of Appeals in Mandel Brothers
had interpreted the phrase “ ‘any other’ ” as rendering the
relative clause (“ ‘who is engaged in dealing commercially’ ”)
applicable to all the specifically listed categories. 359 U. S.,
at 389. This Court unanimously reversed, concluding that
the “limiting clause is to be applied only to the last anteced-
ent.” Id., at 389, and n. 4 (citing 2 J. Sutherland, Statutory
Construction § 4921 (3d ed. 1943)).
An example will illustrate the error of the Third Circuit’s
perception that the specifically enumerated “previous work”
“must” be treated the same as the more general reference to
“any other kind of substantial gainful work.” 294 F. 3d, at
572. Consider, for example, the case of parents who, before
leaving their teenage son alone in the house for the weekend,
warn him, “You will be punished if you throw a party or
engage in any other activity that damages the house.” If
the son nevertheless throws a party and is caught, he should
hardly be able to avoid punishment by arguing that the house
was not damaged. The parents proscribed (1) a party, and
(2) any other activity that damages the house. As far as
appears from what they said, their reasons for prohibiting
the home-alone party may have had nothing to do with dam-
age to the house—for instance, the risk that underage drink-
ing or sexual activity would occur. And even if their only
concern was to prevent damage, it does not follow from the
fact that the same interest underlay both the specific and the
general prohibition that proof of impairment of that interest
is required for both. The parents, foreseeing that assess-
ment of whether an activity had in fact “damaged” the house

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could be disputed by their son, might have wished to pre-
clude all argument by specifying and categorically prohibit-
ing the one activity—hosting a party—that was most likely
to cause damage and most likely to occur.
The Third Circuit suggested that interpreting the statute
as does the SSA would lead to “absurd results.” Ibid. See
also Kolman v. Sullivan, 925 F. 2d 212, 213 (CA7 1991) (the
fact that a claimant could perform a past job that no longer
exists would not be “a rational ground for denying benefits”).
The court could conceive of “no plausible reason why Con-
gress might have wanted to deny benefits to an otherwise
qualified person simply because that person, although unable
to perform any job that actually exists in the national econ-
omy, could perform a previous job that no longer exists.”
294 F. 3d, at 572–573. But on the very next page the Third
Circuit conceived of just such a plausible reason, namely, that
“in the vast majority of cases, a claimant who is found to
have the capacity to perform her past work also will have
the capacity to perform other types of work.” Id., at 574,
n. 5. The conclusion which follows is that Congress could
have determined that an analysis of a claimant’s physical and
mental capacity to do his previous work would “in the vast
majority of cases” serve as an effective and efficient adminis-
trative proxy for the claimant’s ability to do some work that
does exist in the national economy. Such a proxy is useful
because the step-five inquiry into whether the claimant’s cu-
mulative impairments preclude him from finding “other”
work is very difficult, requiring consideration of “each of
th[e] [vocational] factors and . . . an individual assessment of
each claimant’s abilities and limitations,” Heckler v. Camp-
bell, 461 U. S. 458, 460–461, n. 1 (1983) (citing 20 CFR
§§ 404.1545–404.1565 (1982)). There is good reason to use a
workable proxy that avoids the more expansive and individu-
alized step-five analysis. As we have observed, “[t]he Social
Security hearing system is ‘probably the largest adjudicative

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agency in the western world.’ . . . The need for efficiency is
self-evident.” 461 U. S., at 461, n. 2 (citation omitted).
The Third Circuit rejected this proxy rationale because it
would produce results that “may not always be true, and . . .
may not be true in this case.” 294 F. 3d, at 576. That logic
would invalidate a vast number of the procedures employed
by the administrative state. To generalize is to be impre-
cise. Virtually every legal (or other) rule has imperfect ap-
plications in particular circumstances. Cf. Bowen v. Yuck-
ert, 482 U. S. 137, 157 (1987) (O’Connor, J., concurring) (“To
be sure the Secretary faces an administrative task of stag-
gering proportions in applying the disability benefits provi-
sions of the Social Security Act. Perfection in processing
millions of such claims annually is impossible”). It is true
that, under the SSA’s interpretation, a worker with severely
limited capacity who has managed to find easy work in a
declining industry could be penalized for his troubles if the
job later disappears. It is also true, however, that under
the Third Circuit’s interpretation, impaired workers in de-
clining or marginal industries who cannot do “other” work
could simply refuse to return to their jobs—even though the
jobs remain open and available—and nonetheless draw dis-
ability benefits. The proper Chevron inquiry is not whether
the agency construction can give rise to undesirable results
in some instances (as here both constructions can), but rather
whether, in light of the alternatives, the agency construction
is reasonable. In the present case, the SSA’s authoritative
interpretation certainly satisfies that test.
We have considered respondent’s other arguments and find
them to be without merit.
* * *
We need not decide today whether § 423(d)(2)(A) compels
the interpretation given it by the SSA. It suffices to con-
clude, as we do, that § 423(d)(2)(A) does not unambiguously
require a different interpretation, and that the SSA’s regula-

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tion is an entirely reasonable interpretation of the text.
The judgment of the Court of Appeals is reversed.
It is so ordered.