MEACHAM et al. v. KNOLLS ATOMIC POWER LABORATORY, aka KAPL, INC., et al.

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84 OCTOBER TERM, 2007
Syllabus
MEACHAM et al. v. KNOLLS ATOMIC POWER
LABORATORY, aka KAPL, INC., et al.
certiorari to the united states court of appeals for
the second circuit
No. 06–1505. Argued April 23, 2008—Decided June 19, 2008
When the National Government ordered its contractor, respondent Knolls,
to reduce its work force, Knolls had its managers score their subordi
nates on “performance,” “flexibility,” and “critical skills”; these scores,
along with points for years of service, were used to determine who was
laid off. Of the 31 employees let go, 30 were at least 40 years old.
Petitioners (Meacham, for short) were among those laid off, and they
filed this suit asserting, inter alia, a disparate-impact claim under the
Age Discrimination in Employment Act of 1967 (ADEA), 29 U. S. C.
§ 621 et seq. To show such an impact, Meacham relied on a statistical
expert’s testimony that results so skewed according to age could rarely
occur by chance; and that the scores for “flexibility” and “criticality,”
over which managers had the most discretionary judgment, had the
firmest statistical ties to the outcomes. The jury found for Meacham
on the disparate-impact claim, and the Second Circuit initially affirmed.
This Court vacated the judgment and remanded in light of its interven
ing decision in Smith v. City of Jackson, 544 U. S. 228. The Second
Circuit then held for Knolls, finding its prior ruling untenable because
it had applied a “business necessity” standard rather than a “reasonable
ness” test in assessing the employer’s reliance on factors other than age
in the layoff decisions, and because Meacham had not carried the burden
of persuasion as to the reasonableness of Knolls’s non-age factors.
Held: An employer defending a disparate-impact claim under the ADEA
bears both the burden of production and the burden of persuasion for
the “reasonable factors other than age” (RFOA) affirmative defense
under § 623(f)(1). Pp. 91–102.
(a) The ADEA’s text and structure indicate that the RFOA exemp
tion creates an affirmative defense, for which the burden of persuasion
falls on the employer. The RFOA exemption is listed alongside one
for bona fide occupational qualifications (BFOQ), which the Court has
recognized to be an affirmative defense: “It shall not be unlawful for an
employer . . . to take any action otherwise prohibited under subsections
(a), (b), (c), or (e) . . . where age is a [BFOQ] reasonably necessary to
the normal operation of the particular business, or where the differenti
ation is based on [RFOA] . . . .” § 623(f)(1). Given that the statute

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lays out its exemptions in a provision separate from the general prohibi
tions in §§ 623(a)–(c), (e), and expressly refers to the prohibited conduct
as such, it is no surprise that this Court has spoken of both the BFOQ
and RFOA as being among the ADEA’s “five affirmative defenses,”
Trans World Airlines, Inc. v. Thurston, 469 U. S. 111, 122. This read
ing follows the familiar principle that “[w]hen a proviso . . . carves an
exception out of the body of a statute or contract those who set up such
exception must prove it,” Javierre v. Central Altagracia, 217 U. S. 502,
508. As this longstanding convention is part of the backdrop against
which the Congress writes laws, the Court respects it unless there is
compelling reason to think that Congress put the burden of persuasion
on the other side. See Schaffer v. Weast, 546 U. S. 49, 57–58. The
Court has given this principle particular weight in enforcing the Fair
Labor Standards Act of 1938 (FLSA), Corning Glass Works v. Bren
nan, 417 U. S. 188, 196–197; and it has also recognized that “the ADEA
[is] enforced in accordance with the ‘powers, remedies, and procedures’
of the FLSA,” Lorillard v. Pons, 434 U. S. 575, 580. Nothing in
§ 623(f)(1) suggests that Congress meant it to march out of step with
either the general or specifically FLSA default rules placing the burden
of proving an exemption on the party claiming it. Any further doubt
would be dispelled by the natural implication of the “otherwise prohib
ited” language prefacing the BFOQ and RFOA defenses. Pp. 91–95.
(b) Knolls argues that because the RFOA clause bars liability where
action is taken for reasons “other than age,” it should be read as mere
elaboration on an element of liability. But City of Jackson confirmed
that § 623(a)(2)’s prohibition extends to practices with a disparate im
pact, inferring this result in part from the presence of the RFOA provi
sion. 544 U. S., at 239, 243. And City of Jackson made it clear that
action based on a “factor other than age” is the very premise for
disparate-impact liability, not a negation of it or a defense to it. Thus,
it is assumed that a non-age factor was at work in such a case, and
the focus of the RFOA defense is on whether the factor relied on was
“reasonable.” Pp. 95–96.
(c) The business necessity test has no place in ADEA disparate
impact cases; applying both that test and the RFOA defense would en
tail a wasteful and confusing structure of proof. The absence of a busi
ness necessity enquiry does not diminish, however, the reasons already
given for reading the RFOA as an affirmative defense. City of Jackson
cannot be read as implying that the burden of proving any business
related defense falls on the plaintiff, for it confirmed that the BFOQ is
an affirmative defense, see 544 U. S., at 233, n. 3. Moreover, in refer
ring to “Wards Cove’s . . . interpretation of . . . identical language [in
Title VII],” City of Jackson could not have had the RFOA clause in

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86 MEACHAM v. KNOLLS ATOMIC POWER LABORATORY
Syllabus
mind, for Title VII has no like-worded defense. And as Wards Cove
did not purport to construe any Title VII defenses, only an over-reading
of City of Jackson would find in it an assumption that Wards Cove has
anything to say about statutory defenses in the ADEA. Pp. 97–100.
(d) City of Jackson confirmed that an ADEA disparate-impact plain
tiff must “ ‘ “isolat[e] and identif[y] the specific employment practices
that are allegedly responsible for any observed statistical disparities.” ’ ”
544 U. S., at 241. This is not a trivial burden, and it ought to allay some
of the concern that recognizing an employer’s burden of persuasion on
an RFOA defense will encourage strike suits or nudge plaintiffs with
marginal cases into court; but in the end, such concerns have to be
directed at Congress, which set the balance by both creating the RFOA
exemption and writing it in the orthodox format of an affirmative de
fense. Pp. 100–102.
461 F. 3d 134, vacated and remanded.
Souter, J., delivered the opinion of the Court, in which Roberts, C. J.,
and Stevens, Kennedy, Ginsburg, and Alito, JJ., joined, and in which
Thomas, J., joined as to Parts I and II–A. Scalia, J., filed an opinion
concurring in the judgment, post, p. 102. Thomas, J., filed an opinion
concurring in part and dissenting in part, post, p. 104. Breyer, J., took
no part in the consideration or decision of the case.
Kevin K. Russell argued the cause for petitioners. With
him on the briefs were Amy Howe, Pamela S. Karlan, John
B. DuCharme, and Joseph C. Berger.
Daryl Joseffer argued the cause for the United States as
amicus curiae urging reversal. On the brief were former
Solicitor General Clement, Acting Solicitor General Garre,
Leondra R. Kruger, Ronald S. Cooper, Carolyn L. Wheeler,
and Barbara L. Sloan.
Seth P. Waxman argued the cause for respondents. With
him on the brief were Paul R. Q. Wolfson, Heather M. Za
chary, Anthony M. Deardurff, Margaret A. Clemens, and
John E. Higgins.*
*Briefs of amici curiae urging affirmance were filed for the Chamber
of Commerce of the United States of America by Patricia A. Millett,
Donald R. Livingston, Robin S. Conrad, and Shane Brennan; for the
Employment and Labor Law Committee of the Association of Corporate
Counsel by David E. Nagle; for the Equal Employment Advisory Council

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Opinion of the Court
Justice Souter delivered the opinion of the Court.
A provision of the Age Discrimination in Employment Act
of 1967 (ADEA), 81 Stat. 602, as amended, 29 U. S. C. § 621
et seq., creates an exemption for employer actions “otherwise
prohibited” by the ADEA but “based on reasonable fac
tors other than age” (RFOA). § 623(f)(1). The question is
whether an employer facing a disparate-impact claim and
planning to defend on the basis of RFOA must not only
produce evidence raising the defense, but also persuade the
factfinder of its merit. We hold that the employer must do
both.
I
The National Government pays private companies to do
some of the work maintaining the Nation’s fleet of nuclear
powered warships. One such contractor is respondent
KAPL, Inc. (Knolls), the operator of the Government’s
Knolls Atomic Power Laboratory, which has a history dating
back to the first nuclear-powered submarines in the 1950s.
The United States Navy and the Department of Energy
jointly fund Knolls’s operations, decide what projects it
should pursue, and set its annual staffing limits. In recent
years, Knolls has been charged with designing prototype
naval nuclear reactors and with training Navy personnel to
run them.
The demands for naval nuclear reactors changed with the
end of the Cold War, and for fiscal year 1996 Knolls was or
dered to reduce its work force. Even after 100 or so em
ployees chose to take the company’s ensuing buyout offer,
et al. by Rae T. Vann, Karen R. Harned, and Elizabeth Milito; for General
Electric Co. by Peter Buscemi; and for the National School Boards Associ
ation by Maree F. Sneed, John W. Borkowski, Audrey J. Anderson,
Thomas B. Leary, Gil A. Abramson, Francisco M. Negron, Jr., Thomas
E. M. Hutton, and Lisa E. Soronen.
Laurie A. McCann, Melvin Radowitz, and Paul W. Mollica filed a brief
for AARP et al. as amici curiae.

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Knolls was left with 30-some jobs to cut.1 Petitioners (Mea
cham, for short) are among those laid off in the resulting
“involuntary reduction in force.” Brief for Petitioners 6.
In order to select those for layoff, Knolls told its man
agers to score their subordinates on three scales, “perform
ance,” “flexibility,” and “critical skills.” 2 The scores were
summed, along with points for years of service, and the
totals determined who should be let go.
Of the 31 salaried employees laid off, 30 were at least
40 years old.3 Twenty-eight of them sued, raising both
disparate-treatment (discriminatory intent) and disparate
impact (discriminatory result) claims under the ADEA and
state law, alleging that Knolls “designed and implemented
its workforce reduction process to eliminate older employees
and that, regardless of intent, the process had a discrimina
tory impact on ADEA-protected employees.” Meacham v.
Knolls Atomic Power Laboratory, 381 F. 3d 56, 61 (CA2
2004) (Meacham I). To show a disparate impact, the work
ers relied on a statistical expert’s testimony to the effect
that results so skewed according to age could rarely occur
1 The naval reactors program had lowered Knolls’s staffing limit by 108
people; as Knolls also had to hire 35 new employees for work existing
personnel could not do, a total of 143 jobs would have to go.
2 The “performance” score was based on the worker’s two most recent
appraisals. The “flexibility” instruction read: “Rate the employee’s flexi
bility within the Laboratory. Can his or her documented skills be used
in other assignments that will add value to current or future Lab work?
Is the employee retrainable for other Lab assignments?” The “critical
skills” instruction read: “How critical are the employee’s skills to continu
ing work in the Lab? Is the individual’s skill a key technical resource
for the [naval reactors] program? Is the skill readily accessible within
the Lab or generally available from the external market?” App. 94–95
(emphasis in original).
3 For comparison: after the voluntary buyouts, 1,203 out of 2,063 salaried
workers (or 58%) were at least 40 years old; and of the 245 who were at
risk of involuntary layoff, and therefore included in the rankings scheme,
179 (or 73%) were 40 or over. Meacham v. Knolls Atomic Power Labora
tory, 185 F. Supp. 2d 193, 203 (NDNY 2002).

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by chance; 4 and that the scores for “flexibility” and “critical
ity,” over which managers had the most discretionary judg
ment, had the firmest statistical ties to the outcomes. Id.,
at 65.
The jury found for Meacham on the disparate-impact claim
(but not on the disparate-treatment claim). The Court of
Appeals affirmed, after examining the verdict through the
lens of the so-called “burden shifting” scheme of inference
spelled out in Wards Cove Packing Co. v. Atonio, 490 U. S.
642 (1989). See Meacham I, supra, at 74–76.5 After Knolls
sought certiorari, we vacated the judgment and remanded
for further proceedings in light of Smith v. City of Jackson,
544 U. S. 228 (2005), decided while Knolls’s petition was
pending, see 544 U. S. 957 (2005).
On remand, the same Court of Appeals panel ruled in favor
of Knolls, over a dissent. 461 F. 3d 134 (CA2 2006) (Mea
cham II) (case below). The majority found its prior ruling
“untenable” because it had applied the Wards Cove “business
necessity” standard rather than a “reasonableness” test, con
trary to City of Jackson; and on the latter standard, Mea
cham, the employee, had not carried the burden of persua
sion. 461 F. 3d, at 140–141, 144 (internal quotation marks
4 The expert cut the data in different ways, showing the chances to be
1 in 348,000 (based on a population of all 2,063 salaried workers); 1 in 1,260
(based on a population of the 245 workers at risk of layoff); or 1 in 6,639
(when the analysis was broken down by sections of the company). Mea
cham I, 381 F. 3d, at 64–65.
5 Taking the Wards Cove steps in turn, the Court of Appeals concluded
that the “jury could have found that the degree of subjective decision
making allowed in the [layoff procedure] created the disparity,” 381 F. 3d,
at 74; that the employer had answered with evidence of a “facially legiti
mate business justification,” a need “to reduce its workforce while still
retaining employees with skills critical to the performance of [Knolls’s]
functions,” ibid. (internal quotation marks omitted); and that petitioners
would prevail nonetheless because “[a]t least one suitable alternative is
clear from the record,” that Knolls “could have designed [a procedure]
with more safeguards against subjectivity, in particular, tests for critical
ity and flexibility that are less vulnerable to managerial bias,” id., at 75.

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omitted).6 In dissent, Judge Pooler took issue with the ma
jority for confusing business justifications under Wards Cove
with the statutory RFOA exemption, which she read to be
an affirmative defense with the burden of persuasion falling
on defendants. 461 F. 3d, at 147, 149–152.7
Meacham sought certiorari, noting conflicting decisions as
signing the burden of persuasion on the reasonableness of
the factor other than age; the Court of Appeals in this case
placed it on the employee (to show the non-age factor unrea
sonable), but the Ninth Circuit in Criswell v. Western Air
lines, Inc., 709 F. 2d 544, 552 (1983), had assigned it to the
employer (to show the factor was a reasonable one). In fact
it was in Criswell that we first took up this question, only to
find it not well posed in that case. Western Air Lines, Inc.
v. Criswell, 472 U. S. 400, 408, n. 10 (1985). We granted cer
tiorari, 552 U. S. 1162 (2008), and now vacate the judgment
of the Second Circuit and remand.8
6 Distinguishing the two tests mattered, the Court of Appeals explained,
because even though “[t]here may have been other reasonable ways for
[Knolls] to achieve its goals (as we held in [Meacham I]), . . . the one
selected was not unreasonable.” Meacham II, 461 F. 3d, at 146 (citation
and internal quotation marks omitted). The burden of persuasion for
either test was said to fall on the plaintiff, however, because “the employer
is not to bear the ultimate burden of persuasion with respect to the legiti
macy of its business justification.” Id., at 142 (citing Wards Cove, 490
U. S., at 659–660; internal quotation marks omitted). The majority took
note of the textual signs that the RFOA was an affirmative defense, but
set them aside because “City of Jackson . . . emphasized that there are
reasonable and permissible employment criteria that correlate with age,”
thereby leaving it to plaintiffs to prove that a criterion is not reasonable.
461 F. 3d, at 142–143.
7 In Judge Pooler’s view, a jury “could permissibly find that defendants
had not established a RFOA based on the unmonitored subjectivity of
[Knolls’s] plan as implemented.” Id., at 153 (dissenting opinion).
8 Petitioners also sought certiorari as to “[w]hether respondents’ practice
of conferring broad discretionary authority upon individual managers to
decide which employees to lay off during a reduction in force constituted
a ‘reasonable factor other than age’ as a matter of law.” Pet. for Cert. i.
We denied certiorari on this question and express no views on it here.

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II
A
The ADEA’s general prohibitions against age discrimina
tion, 29 U. S. C. §§ 623(a)–(c), (e), are subject to a separate
provision, § 623(f), creating exemptions for employer prac
tices “otherwise prohibited under subsections (a), (b), (c), or
(e).” The RFOA exemption is listed in § 623(f) alongside
one for bona fide occupational qualifications (BFOQ): “It shall
not be unlawful for an employer . . . to take any action other
wise prohibited under subsections (a), (b), (c), or (e) . . . where
age is a bona fide occupational qualification reasonably neces
sary to the normal operation of the particular business, or
where the differentiation is based on reasonable factors other
than age . . . .” § 623(f)(1).
Given how the statute reads, with exemptions laid out
apart from the prohibitions (and expressly referring to the
prohibited conduct as such), it is no surprise that we have
already spoken of the BFOQ and RFOA provisions as being
among the ADEA’s “five affirmative defenses,” Trans World
Airlines, Inc. v. Thurston, 469 U. S. 111, 122 (1985). After
looking at the statutory text, most lawyers would accept that
characterization as a matter of course, thanks to the familiar
principle that “[w]hen a proviso . . . carves an exception out
of the body of a statute or contract those who set up such
exception must prove it.” Javierre v. Central Altagracia,
217 U. S. 502, 508 (1910) (opinion for the Court by Holmes,
J.); see also FTC v. Morton Salt Co., 334 U. S. 37, 44–45
(1948) (“[T]he burden of proving justification or exemption
under a special exception to the prohibitions of a statute gen
erally rests on one who claims its benefits . . . ”); United
States v. First City Nat. Bank of Houston, 386 U. S. 361,
366 (1967) (citing Morton Salt Co., supra, at 44–45). That
longstanding convention is part of the backdrop against
which the Congress writes laws, and we respect it unless we
have compelling reasons to think that Congress meant to put

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the burden of persuasion on the other side. See Schaffer v.
Weast, 546 U. S. 49, 57–58 (2005) (“Absent some reason to
believe that Congress intended otherwise, therefore, we will
conclude that the burden of persuasion lies where it usually
falls, upon the party seeking relief ”).
We have never been given any reason for a heterodox take
on the RFOA clause’s nearest neighbor, and our prior cases
recognize that the BFOQ clause establishes an affirmative
defense against claims of disparate treatment. See, e. g.,
City of Jackson, 544 U. S., at 233, n. 3; Western Air Lines, Inc.,
supra, at 414–419, and nn. 24, 29. We have likewise given
the affirmative defense construction to the exemption in the
Equal Pay Act of 1963 for pay differentials based on “any
other factor other than sex,” Corning Glass Works v. Bren
nan, 417 U. S. 188, 196 (1974) (internal quotation marks omit
ted); and there, we took account of the particular weight
given to the interpretive convention already noted, when en
forcing the Fair Labor Standards Act of 1938 (FLSA), id., at
196–197 (“[T]he general rule [is] that the application of an
exemption under the [FLSA] is a matter of affirmative de
fense on which the employer has the burden of proof ”).
This focus makes the principle of construction the more in
structive in ADEA cases: “in enacting the ADEA, Congress
exhibited both a detailed knowledge of the FLSA provisions
and their judicial interpretation and a willingness to depart
from those provisions regarded as undesirable or inappropri
ate for incorporation,” Lorillard v. Pons, 434 U. S. 575, 581
(1978). And we have remarked and relied on the “signifi
cant indication of Congress’ intent in its directive that the
ADEA be enforced in accordance with the ‘powers, remedies,
and procedures’ of the FLSA.” Id., at 580 (quoting 29
U. S. C. § 626(b); emphasis deleted); see also Fogerty v. Fan
tasy, Inc., 510 U. S. 517, 528 (1994) (applying reasoning of
Lorillard); Thurston, supra, at 126 (same). As against this
interpretive background, there is no hint in the text that
Congress meant § 623(f)(1) to march out of step with either

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the general or specifically FLSA default rules placing the
burden of proving an exemption on the party claiming it.
With these principles and prior cases in mind, we find it
impossible to look at the text and structure of the ADEA
and imagine that the RFOA clause works differently from
the BFOQ clause next to it. Both exempt otherwise illegal
conduct by reference to a further item of proof, thereby cre
ating a defense for which the burden of persuasion falls on
the “one who claims its benefits,” Morton Salt Co., supra, at
44–45, the “party seeking relief,” Schaffer, supra, at 57–58,
and here, “the employer,” Corning Glass Works, supra,
at 196.
If there were any doubt, the stress of the idiom “otherwise
prohibited,” prefacing the BFOQ and RFOA conditions,
would dispel it.9 The implication of affirmative defense is
9 We do not need to seek further relief from doubt by looking to the
Equal Employment Opportunity Commission (EEOC) regulations on bur
dens of proof in ADEA cases. The parties focus on two of them, but
we think neither clearly answers the question here. One of them the
Government has disavowed as overtaken by our decision in Smith v. City
of Jackson, 544 U. S. 228 (2005), Brief for United States as Amicus Curiae
16, n. 1 (noting that 29 CFR § 1625.7(d) (2007) “takes a position that does
not survive” City of Jackson), for the regulation seems to require a show
ing of business necessity as a part of the RFOA defense. Compare 29
CFR § 1625.7(d) (“When an employment practice, including a test, is
claimed as a basis for different treatment . . . on the grounds that it is a
‘factor other than’ age, and such a practice has an adverse impact on indi
viduals within the protected age group, it can only be justified as a busi
ness necessity”) with City of Jackson, supra, at 243 (“Unlike the business
necessity test, which asks whether there are other ways for the employer
to achieve its goals that do not result in a disparate impact on a protected
class, the reasonableness inquiry includes no such requirement”). And
the second regulation would take a bit of stretching to cover disparate
impact cases, for its text speaks in terms of disparate treatment. See 29
CFR § 1625.7(e) (concerning use of the RFOA defense against an “individ
ual claim of discriminatory treatment”). The EEOC has lately proposed
rulemaking that would revise both of these regulations, eliminating any
reference to “business necessity” and placing the burden of proof on the
employer “[w]henever the exception of ‘a reasonable factor other than age’
is raised.” 73 Fed. Reg. 16807–16809 (2008) (proposed 29 CFR § 1625.7(e)).

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underscored by contrasting § 623(f)(1) with the section of the
ADEA at issue in Public Employees Retirement System of
Ohio v. Betts, 492 U. S. 158 (1989), and by the way Congress
responded to our decision there. In Betts, we said the issue
was whether a provision in a former version of § 623(f)(2),
one about employee benefit plans, merely “redefine[d] the el
ements of a plaintiff ’s prima facie case,” or instead “estab
lish[ed] a defense” to what “otherwise would be a violation
of the Act.” Id., at 181.10 Although the provision contained
no “otherwise prohibited” kind of language, we said that it
“appears on first reading to describe an affirmative defense.”
Ibid. We nonetheless thought that this more natural view
(which we had taken in Thurston) was overridden by evi
dence of legislative history, by the peculiarity of a pretext
revealing condition in the phrasing of the provision (that a
benefit plan “not [be] a subterfuge to evade the purposes” of
the ADEA), and by the parallel with a prior case construing
an “analogous provision of Title VII” of the Civil Rights Act
of 1964 (analogous because it also contained a pretext
revealing condition). 492 U. S., at 181. A year later, how
ever, Congress responded to Betts by enacting the Older
Workers Benefit Protection Act, 104 Stat. 978, avowedly to
“restore the original congressional intent” that the ADEA’s
benefits provision be read as an affirmative defense, id.,
§ 101. What is instructive on the question at hand is that,
in clarifying that § 623(f)(2) specifies affirmative defenses,
Congress not only set the burden in so many words but also
added the phrase “otherwise prohibited” as a part of the
preface ( just as in the text of § 623(f)(1)).11 Congress thus
10 The provision read: “It shall not be unlawful for an employer . . . to
observe the terms of . . . any bona fide employee benefit plan such as a
retirement, pension, or insurance plan, which is not a subterfuge to evade
the purposes of this chapter . . . because of the age of such individual.”
29 U. S. C. § 623(f)(2) (1982 ed.).
11 Congress surely could not have meant this phrase to contradict its
express allocation of the burden, in the same amendment. But that would

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confirmed the natural implication that we find in the “other
wise prohibited” language in § 623(f)(1): it refers to an excuse
or justification for behavior that, standing alone, violates the
statute’s prohibition. The amendment in the aftermath of
Betts shows that Congress understands the phrase the same
way we naturally read it, as a clear signal that a defense
to what is “otherwise prohibited” is an affirmative defense,
entirely the responsibility of the party raising it.
B
Knolls ventures that, regardless, the RFOA provision
should be read as mere elaboration on an element of liability.
Because it bars liability where action is taken for reasons
“other than age,” the argument goes, the provision must be
directed not at justifying age discrimination by proof of some
extenuating fact but at negating the premise of liability
under § 623(a)(2), “because of . . . age.”
The answer to this argument, however, is City of Jackson,
where we confirmed that the prohibition in § 623(a)(2) ex
tends to practices with a disparate impact, inferring this
result in part from the presence of the RFOA provision
at issue here.12 We drew on the recognized distinction
between disparate-treatment and disparate-impact forms of
liability, and explained that “the very definition of disparate
impact” was that “an employer who classifies his employees
without respect to age may still be liable under the terms
be the upshot of Knolls’s suggestion that the only way to read the word
“otherwise” as not redundant in the phrase “otherwise prohibited under
subsections (a), (b), (c), or (e)” is to say that the word must refer only to
§ 623(f)(1) (2000 ed.) itself, implying that § 623(f)(1) must be a liability
creating provision for which the burden falls on the plaintiff. Brief for
Respondents 33, and n. 7. Besides, this argument proves too much, for it
implies that even the BFOQ exemption is not an affirmative defense.
12 In doing so, we expressly rejected the so-called “safe harbor” view of
the RFOA provision. See City of Jackson, 544 U. S., at 238–239 (plurality
opinion); id., at 252–253 (O’Connor, J., concurring in judgment) (describing
“safe harbor” view).

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96 MEACHAM v. KNOLLS ATOMIC POWER LABORATORY
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of this paragraph if such classification adversely affects the
employee because of that employee’s age.” 544 U. S., at 236,
n. 6 (plurality opinion); id., at 243 (Scalia, J., concurring in
part and concurring in judgment) (expressing agreement
with “all of the Court’s reasoning” in the plurality opinion,
but finding it a basis for deference to the EEOC rather than
for independent judicial decision). We emphasized that
these were the kinds of employer activities, “otherwise pro
hibited” by § 623(a)(2), that were mainly what the statute
meant to test against the RFOA condition: because “[i]n
disparate-impact cases . . . the allegedly ‘otherwise prohib
ited’ activity is not based on age,” it is “in cases involving
disparate-impact claims that the RFOA provision plays its
principal role by precluding liability if the adverse impact
was attributable to a nonage factor that was ‘reasonable.’ ”
Id., at 239 (plurality opinion).
Thus, in City of Jackson, we made it clear that in the typi
cal disparate-impact case, the employer’s practice is “without
respect to age” and its adverse impact (though “because of
age”) is “attributable to a nonage factor”; so action based on
a “factor other than age” is the very premise for disparate
impact liability in the first place, not a negation of it or a
defense to it. The RFOA defense in a disparate-impact
case, then, is not focused on the asserted fact that a non-age
factor was at work; we assume it was. The focus of the de
fense is that the factor relied upon was a “reasonable” one for
the employer to be using. Reasonableness is a justification
categorically distinct from the factual condition “because of
age” and not necessarily correlated with it in any particular
way: a reasonable factor may lean more heavily on older
workers, as against younger ones, and an unreasonable factor
might do just the opposite.13
13 The factual causation that § 623(a)(2) describes as practices that “de
prive or tend to deprive . . . or otherwise adversely affect [employees] . . .
because of . . . age” is typically shown by looking to data revealing the
impact of a given practice on actual employees. See, e. g., City of Jack

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III
The Court of Appeals majority rejected the affirmative
defense reading and arrived at its position on the burden of
proof question by a different route: because it read our deci
sion in City of Jackson as ruling out the so-called “business
necessity” enquiry in ADEA cases, the court concluded that
the RFOA defense “replaces” it and therefore must conform
to its burden of persuasion resting on the complaining party.
But the court’s premise (that City of Jackson modified the
“business necessity” enquiry) is mistaken; this alone would
be reason enough to reject its approach. And although we
are now satisfied that the business necessity test should have
no place in ADEA disparate-impact cases, we agree with the
Government that this conclusion does not stand in the way
of our holding that the RFOA exemption is an affirmative
defense. See Brief for United States as Amicus Curiae
25–27.
To begin with, when the Court of Appeals further inferred
from the City of Jackson reference to Wards Cove that the
Wards Cove burden of persuasion (on the employee, for the
business necessity enquiry) also applied to the RFOA de
fense, it gave short shrift to the reasons set out in Part II–A,
son, supra, at 241 (opinion of the Court); cf. Wards Cove Packing Co. v.
Atonio, 490 U. S. 642, 657, 658–659 (1989) (under Title VII, “specific causa
tion” is shown, and a “prima facie case” is “establish[ed],” when plaintiff
identifies a specific employment practice linked to a statistical disparity);
Watson v. Fort Worth Bank & Trust, 487 U. S. 977, 995 (1988) (plurality
opinion) (in Title VII cases, “statistical disparities must be sufficiently
substantial that they raise . . . an inference of causation”).
This enquiry would be muddled if the value, “reasonableness,” were to
become a factor artificially boosting or discounting the factual strength of
the causal link, or the extent of the measured impact. It would open the
door to incoherent undershooting, for example, if defendants were heard
to say that an impact is “somewhat less correlated with age, seeing as the
factor is a reasonable one”; and it would be overshooting to make them
show that the impact is “not correlated with age, and the factor is reason
able, besides.”

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supra, for reading RFOA as an affirmative defense (with the
burden on the employer). But we think that even on its own
terms, City of Jackson falls short of supporting the Court of
Appeals’s conclusion.
Although City of Jackson contains the statement that
“Wards Cove’s pre-1991 interpretation of Title VII’s identical
language remains applicable to the ADEA,” 544 U. S., at 240,
City of Jackson made only two specific references to aspects
of the Wards Cove interpretation of Title VII that might
have “remain[ed] applicable” in ADEA cases. One was to
the existence of disparate-impact liability, which City of
Jackson explained was narrower in ADEA cases than under
Title VII. The other was to a plaintiff-employee’s burden
of identifying which particular practices allegedly cause an
observed disparate impact, which is the employee’s burden
under both the ADEA and the pre-1991 Title VII. See 544
U. S., at 241. Neither of these references, of course, is at
odds with the view of RFOA as an affirmative defense.
If, indeed, City of Jackson’s reference to Wards Cove could
be read literally to include other aspects of the latter case,
beyond what mattered in City of Jackson itself, the unto
ward consequences of the broader reading would rule it out.
One such consequence is embraced by Meacham, who argues
both that the Court of Appeals was wrong to place the bur
den of persuasion for the RFOA defense on the employee,
and that the court was right in thinking that City of Jackson
adopted the Wards Cove burden of persuasion on what Mea
cham views as one element of an ADEA impact claim. For
Meacham takes the position that an impact plaintiff like him
self has to negate business necessity in order to show that
the employer’s actions were “otherwise prohibited”; only
then does the RFOA (with the burden of persuasion on the
employer) have a role to play. To apply both tests, however,
would force the parties to develop (and the court or jury to
follow) two overlapping enquiries: first, whether the employ
ment practice at issue (based on a factor other than age) is

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supported by a business justification; and second, whether
that factor is a reasonable one. Depending on how the first
enquiry proceeds, a plaintiff might directly contest the force
of the employer’s rationale, or else try to show that the em
ployer invoked it as a pretext by pointing (for example) to
alternative practices with less of a disparate impact. See
Wards Cove, 490 U. S., at 658 (“first, a consideration of the
justifications an employer offers for his use of these prac
tices; and second, the availability of alternative practices to
achieve the same business ends, with less racial impact”); see
also id., at 658–661. But even if the plaintiff succeeded at
one or the other, in Meacham’s scheme the employer could
still avoid liability by proving reasonableness.
Here is what is so strange: as the Government says, “[i]f
disparate-impact plaintiffs have already established that a
challenged practice is a pretext for intentional age discrimi
nation, it makes little sense then to ask whether the discrimi
natory practice is based on reasonable factors other than
age.” Brief for United States as Amicus Curiae 26 (empha
sis in original). Conversely, proving the reasonableness de
fense would eliminate much of the point a plaintiff would
have had for showing alternatives in the first place: why
make the effort to show alternative practices with a less dis
criminatory effect (and besides, how would that prove pre
text?), when everyone knows that the choice of a practice
relying on a “reasonable” non-age factor is good enough to
avoid liability? 14 At the very least, developing the reason
ableness defense would be substantially redundant with the
direct contest over the force of the business justification, es
pecially when both enquiries deal with the same, narrowly
14 See City of Jackson, 544 U. S., at 243 (“While there may have been
other reasonable ways for the City to achieve its goals, the one selected
was not unreasonable. Unlike the business necessity test, which asks
whether there are other ways for the employer to achieve its goals that
do not result in a disparate impact on a protected class, the reasonableness
inquiry includes no such requirement”).

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100 MEACHAM v. KNOLLS ATOMIC POWER LABORATORY
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specified practice. It is not very fair to take the remark
about Wards Cove in City of Jackson as requiring such a
wasteful and confusing structure of proof.
Nor is there any good way to read the same line from
City of Jackson as implying that the burden of proving any
business-related defense falls on the plaintiff; most obvi
ously, this would entail no longer taking the BFOQ clause to
be an affirmative defense, which City of Jackson confirmed
that it is, see 544 U. S., at 233, n. 3. What is more, City of
Jackson could not have had the RFOA clause in mind as
“identical” to anything in Title VII (for which a Wards Cove’s
reading might be adopted), for that statute has no like
worded defense. And as Wards Cove did not purport to con
strue any statutory defenses under Title VII, only an over
reading of City of Jackson would find lurking in it an
assumption that Wards Cove has anything to say about stat
utory defenses in the ADEA (never mind one that Title VII
does not have).
IV
As mentioned, where City of Jackson did get help from
our prior reading of Title VII was in relying on Wards Cove
to repeat that a plaintiff falls short by merely alleging a dis
parate impact, or “point[ing] to a generalized policy that
leads to such an impact.” City of Jackson, 544 U. S., at 241.
The plaintiff is obliged to do more: to “isolat[e] and identif[y]
the specific employment practices that are allegedly respon
sible for any observed statistical disparities.” Ibid. (quoting
Wards Cove, supra, at 656; emphasis in original; internal
quotation marks omitted). The aim of this requirement, as
City of Jackson said, is to avoid the “result [of] employers
being potentially liable for ‘the myriad of innocent causes
that may lead to statistical imbalances.’ ” 544 U. S., at 241
(quoting Wards Cove, supra, at 657; some internal quotation
marks omitted). And as the outcome in that case shows, the
requirement has bite: one sufficient reason for rejecting the

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employees’ challenge was that they “ha[d] done little more
than point out that the pay plan at issue [was] relatively less
generous to older workers than to younger workers,” and
“ha[d] not identified any specific test, requirement, or prac
tice within the pay plan that ha[d] an adverse impact on older
workers.” City of Jackson, supra, at 241.
Identifying a specific practice is not a trivial burden, and
it ought to allay some of the concern raised by Knolls’s amici,
who fear that recognizing an employer’s burden of persua
sion on an RFOA defense to impact claims will encourage
strike suits or nudge plaintiffs with marginal cases into
court, in turn inducing employers to alter business practices
in order to avoid being sued. See, e. g., Brief for General
Electric Co. as Amicus Curiae 18–31. It is also to the point
that the only thing at stake in this case is the gap between
production and persuasion; nobody is saying that even the
burden of production should be placed on the plaintiff.
Cf. Schaffer, 546 U. S., at 56 (burden of persuasion answers
“which party loses if the evidence is closely balanced”); id., at
58 (“In truth, however, very few cases will be in evidentiary
equipoise”). And the more plainly reasonable the employ
er’s “factor other than age” is, the shorter the step for that
employer from producing evidence raising the defense, to
persuading the factfinder that the defense is meritorious. It
will be mainly in cases where the reasonableness of the non
age factor is obscure for some reason, that the employer will
have more evidence to reveal and more convincing to do in
going from production to persuasion.
That said, there is no denying that putting employers to
the work of persuading factfinders that their choices are rea
sonable makes it harder and costlier to defend than if em
ployers merely bore the burden of production; nor do we
doubt that this will sometimes affect the way employers do
business with their employees. But at the end of the day,
amici’s concerns have to be directed at Congress, which set
the balance where it is, by both creating the RFOA exemp

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102 MEACHAM v. KNOLLS ATOMIC POWER LABORATORY
Scalia, J., concurring in judgment
tion and writing it in the orthodox format of an affirmative
defense. We have to read it the way Congress wrote it.
* * *
As we have said before, Congress took account of the dis
tinctive nature of age discrimination, and the need to pre
serve a fair degree of leeway for employment decisions with
effects that correlate with age, when it put the RFOA clause
into the ADEA, “significantly narrow[ing] its coverage.”
City of Jackson, 544 U. S., at 233. And as the outcome for
the employer in City of Jackson shows, “it is not surprising
that certain employment criteria that are routinely used may
be reasonable despite their adverse impact on older workers
as a group.” Id., at 241. In this case, we realize that the
Court of Appeals showed no hesitation in finding that Knolls
prevailed on the RFOA defense, though the court expressed
its conclusion in terms of Meacham’s failure to meet the bur
den of persuasion. Whether the outcome should be any dif
ferent when the burden is properly placed on the employer
is best left to that court in the first instance. The judgment
of the Court of Appeals is vacated, and the case is remanded
for further proceedings consistent with this opinion.
It is so ordered.
Justice Breyer took no part in the consideration or deci
sion of this case.
Justice Scalia, concurring in the judgment.
I do not join the majority opinion because the Court an
swers for itself two questions that Congress has left to the
sound judgment of the Equal Employment Opportunity
Commission. As represented by the Solicitor General of the
United States in a brief signed by the Commission’s Gen
eral Counsel, the Commission takes the position that the
reasonable-factor-other-than-age provision is an affirmative
defense on which the employer bears the burden of proof,

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and that, in disparate-impact suits brought under the Age
Discrimination in Employment Act of 1967 (ADEA), that
provision replaces the business-necessity test of Wards Cove
Packing Co. v. Atonio, 490 U. S. 642 (1989).
Neither position was contrived just for this case. Indeed,
the Commission has arguably held its view on the burden-of
proof point for nearly 30 years. See 44 Fed. Reg. 68858,
68861 (1979). Although its regulation applied only to cases
involving “discriminatory treatment,” 29 CFR § 1625.7(e)
(2007), even if that covers only disparate treatment, see ante,
at 93, n. 9, the logic of its extension to disparate-impact
claims is obvious and unavoidable. See Brief for United
States as Amicus Curiae 16, n. 1. At the very least, the
regulation does not contradict the Commission’s current po
sition: It does not say that the employer bears the burden of
proof only in discriminatory-treatment cases.
The Commission’s view on the business-necessity test is
newly minted, but that does not undermine it. The Com
mission has never expressed the contrary view that the fact
finder must consider both business necessity and reasonable
ness when an employer applies a factor that has a disparate
impact on older workers. In fact, before Smith v. City of
Jackson, 544 U. S. 228 (2005), the Commission had not even
considered the relationship between the two standards, be
cause it used to treat the two as identical. See 29 CFR
§ 1625.7(d). After City of Jackson rejected that equation,
see 544 U. S., at 243, the Commission decided that the
business-necessity standard plays no role in ADEA
disparate-impact claims, see Brief for United States as Ami
cus Curiae 25–27, and has even proposed new rules setting
forth that position, see 73 Fed. Reg. 16807–16809 (2008).
Because administration of the ADEA has been placed in
the hands of the Commission, and because the agency’s posi
tions on the questions before us are unquestionably reason
able (as the Court’s opinion ably shows), I defer to the
agency’s views. See Raymond B. Yates, M. D., P. C. Profit

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104 MEACHAM v. KNOLLS ATOMIC POWER LABORATORY
Opinion of Thomas, J.
Sharing Plan v. Hendon, 541 U. S. 1, 24–25 (2004) (Scalia,
J., concurring in judgment). I therefore concur in the
Court’s judgment to vacate the judgment of the Court of
Appeals.
Justice Thomas, concurring in part and dissenting in
part.
I write separately to note that I continue to believe that
disparate-impact claims are not cognizable under the Age
Discrimination in Employment Act of 1967, 29 U. S. C. § 621
et seq. See Smith v. City of Jackson, 544 U. S. 228, 247–268
(2005) (O’Connor, J., joined by Kennedy and Thomas, JJ.,
concurring in judgment). Moreover, I disagree with the
Court’s statement that the “reasonable factors other than
age” (RFOA) exception, § 623(f)(1), is principally relevant in
disparate-impact cases. Compare City of Jackson, supra,
at 251–253 (opinion concurring in judgment), with ante, at
95–96 (citing City of Jackson, supra, at 239 (plurality opin
ion)). I therefore join only Parts I and II–A of the Court’s
opinion because I agree that the RFOA exception is an af
firmative defense—when it arises in disparate-treatment
cases. Here, although the Court of Appeals erred in placing
the burden of proof on petitioners, I would nonetheless af
firm because the only claims at issue are disparate-impact
claims.