Case: 22-1822 Document: 54 Page: 1 Filed: 03/26/2024
`
`
`
`United States Court of Appeals
`for the Federal Circuit
`______________________
`
`LESLIE BOYER,
`Plaintiff-Appellant
`
`v.
`
`UNITED STATES,
`Defendant-Appellee
`______________________
`
`2022-1822
`______________________
`
`Appeal from the United States Court of Federal Claims
`in No. 1:20-cv-00438-ZNS, Judge Zachary N. Somers.
`______________________
`
`Decided: March 26, 2024
`______________________
`
`LACHLAN W. SMITH, Wiggins Childs Pantazis Fisher &
`Goldfarb LLC, Birmingham, AL, argued for plaintiff-appel-
`lant. Also represented by JON C. GOLDFARB.
`
` KARA WESTERCAMP, Commercial Litigation Branch,
`Civil Division, United States Department of Justice, Wash-
`ington, DC, argued for defendant-appellee. Also repre-
`sented by BRIAN M. BOYNTON, CLAUDIA BURKE, PATRICIA M.
`MCCARTHY.
`
` DEBRA D'AGOSTINO, The Federal Practice Group,
`Washington, DC, for amici curiae A Better Balance, Amer-
`ican Medical Women’s Association, California Women
`
`

`

`Case: 22-1822 Document: 54 Page: 2 Filed: 03/26/2024
`
`2
`
`BOYER v. US
`
`Lawyers, California Women’s Law Center, Center for
`Women’s Health & Human Rights, Suffolk University, Chi-
`cago Foundation for Women, Clearinghouse on Women’s
`Issues, Desiree Alliance, Equal Rights Advocates, Faith Ac-
`tion for All, Feminist Majority Foundation, Hadassah, the
`Women’s Zionist Organization of America, Human Rights
`Campaign, If/When/How: Lawyering for Reproductive Jus-
`tice, In Our Own Voice: National Black Women’s Reproduc-
`tive Justice Agenda, In the Public Interest, Indiana
`Community Action Poverty Institute, International Action
`Network for Gender Equity & Law, Lawyers Club of San
`Diego, Legal Aid at Work, Legal Momentum, the Women's
`Legal Defense and Education Fund, NARAL Pro-Choice
`America, National Asian Pacific American Women’s Fo-
`rum, National Association of Women Lawyers, National
`Coalition on Black Civic Participation, National Consum-
`ers League, National Crittenton, National Employment
`Lawyers Association, National Health Care for the Home-
`less Council, National LGBTQ Task Force, National
`Women’s Law Center, National Womens Political Caucus,
`Queen’s Bench Bar Association of the San Francisco Bay
`Area, Religious Coalition for Reproductive Choice, Re-
`proaction, Service Employees International Union, Shriver
`Center on Poverty Law, SisterReach, Washington Lawyers’
`Committee for Civil Rights and Urban Affairs, Women Em-
`ployed, Women Lawyers On Guard Inc., Women’s Bar As-
`sociation of the District of Columbia, Women’s Bar
`Association of the State of New York, Women’s Institute for
`Freedom of the Press, Women’s Law Center of Maryland,
`Women’s Law Project, Women’s Media Center. Also repre-
`sented by JANEI AU; GAYLYNN BURROUGHS, SUNU CHANDY,
`PHOEBE WOLFE, National Women’s Law Center, Washing-
`ton, DC.
` ______________________
`
`Before DYK, CHEN, and STOLL, Circuit Judges.
`DYK, Circuit Judge.
`
`

`

`Case: 22-1822 Document: 54 Page: 3 Filed: 03/26/2024
`
`BOYER v. US
`
`3
`
`Dr. Leslie Boyer brought suit against the United
`States, claiming a violation of the Equal Pay Act (“EPA”),
`29 U.S.C. § 206(d)(1), because the government set her pay
`unequally compared to a male comparator. The Court of
`Federal Claims (“Claims Court”) granted summary judg-
`ment to the United States on the ground that, under the
`EPA, an employer may consider a “factor other than sex,”
`that “Congress permitted the [Veteran’s Administration] to
`use existing or prior pay alone [as a factor other than sex]
`in determining pay rates for new appointees,” and prior
`pay accounted for the differential in this case. J.A. 36. We
`conclude that the EPA applies equally to the United States
`as to other employers and that mere reliance on prior com-
`pensation standing alone is not an affirmative defense to a
`prima facie case under the EPA, unless the employer can
`demonstrate that the prior pay itself was not based on sex.
`We reverse the grant of summary judgment to the United
`States and remand for further proceedings consistent with
`this opinion.
`
`BACKGROUND
`I
`Dr. Boyer was employed by the Veterans Affairs Medi-
`cal Center of Birmingham, Alabama (“BVAMC”) as a clini-
`cal pharmacist in 2015. Six months later, BVAMC hired a
`male clinical pharmacist. Both Dr. Boyer and the male
`comparator were hired according to the federal hiring sys-
`tem, the General Schedule or “GS” system. The federal hir-
`ing system sets salary scales by locality, with each federal
`position assigned a grade. Within each grade, there are a
`series of steps with corresponding salary increases. To hire
`an employee over the minimum rate within a particular
`grade, the agency must make a showing that certain qual-
`ities justify that departure, including superior qualifica-
`tions, special needs of the government, and prior
`compensation. 5 C.F.R. § 531.212.
`
`

`

`Case: 22-1822 Document: 54 Page: 4 Filed: 03/26/2024
`
`4
`
`BOYER v. US
`
`At the time of her hiring, Dr. Boyer was appointed as a
`clinical pharmacist at GS-12, Step 7 with a starting salary
`of $115,364. Although the minimum rate in this locality
`for GS-12 clinical pharmacists was $96,133 at Step 1, Dr.
`Boyer was appointed at Step 7 ($115,364) due, at least in
`part, because of her prior salary, which was $115,003. The
`male comparator was appointed at a GS-12, Step 10, with
`a starting salary of $126,223. His prior salary was
`$130,000.
`There are alleged other differences between the two.
`Dr. Boyer contends that she was more qualified than the
`male comparator, having had seven more years of experi-
`ence after graduating with her doctorate in pharmacy in
`1999. She also contends that she had unique mental health
`work experience as compared to the male comparator. The
`government argues that the male comparator was more
`qualified in other ways, having a master’s degree in biolog-
`ical sciences in addition to his doctorate in pharmacy and
`different work experience.
`Three years after her hiring, Dr. Boyer discovered the
`pay discrepancy. She inquired about the differential with
`Human Resources and eventually, in 2018, filed an Equal
`Employment Opportunity (“EEO”) complaint, alleging
`wage discrimination. The EEO counselor created an inves-
`tigative report in 2019 but did not issue any official conclu-
`sions or recommendations. Two months later, Dr. Boyer
`filed suit in the United States District Court for the North-
`ern District of Alabama, alleging a violation of the EPA.
`Boyer v. Wilkie, No. 2:19-CV-00552 (N.D. Ala. transferred
`Feb. 13, 2020).1
`
`
`
`1 The parties consented to the jurisdiction of a mag-
`istrate judge. ECF No. 11 (May 30, 2019).
`
`

`

`Case: 22-1822 Document: 54 Page: 5 Filed: 03/26/2024
`
`BOYER v. US
`
`5
`
`II
`The Equal Pay Act codifies “the principle of equal pay
`for equal work regardless of sex.” Corning Glass Works v.
`Brennan, 417 U.S. 188, 190 (1974). The EPA provides that
`no employer that is subject to the Act shall discriminate
`between employees of the opposite sex for equal work that
`requires “equal skill, effort, and responsibility, and which
`are performed under similar working conditions.”
`29 U.S.C. § 206(d)(1). The EPA has four exceptions to this
`general principle, where a differential is made pursuant to
`“(i) a seniority system; (ii) a merit system; (iii) a system
`which measures earnings by quantity or quality of produc-
`tion; or (iv) a differential based on any other factor other
`than sex.” Id.
`Under the EPA, the plaintiff has the burden of estab-
`lishing a prima facie case—showing that the employer pays
`employees of the opposite sex who perform substantially
`equal work unequally.2 Corning Glass Works, 417 U.S. at
`195. Once established, the burden of proof shifts to the em-
`ployer to prove that the differential is made pursuant to
`one of the four affirmative defenses. Id. at 196–97; see
`Beck-Wilson v. Principi, 441 F.3d 353, 365 (6th Cir. 2006).
`If the employer successfully establishes that the differen-
`tial was made pursuant to one of the four defenses, the
`
`
`2 The Claims Court noted that in Yant v. United
`States, the Federal Circuit affirmed the grant of summary
`judgment to the government when there was no showing
`that the salary differential was “either historically or pres-
`ently based on sex.” 588 F.3d 1369, 1372 (Fed. Cir. 2009).
`This holding was recently overruled in Moore v. United
`States, which held that a prima facie case under the EPA
`does not require a showing that a pay differential is either
`historically or presently based on sex. 66 F.4th 991, 997
`(Fed. Cir. 2023) (en banc).
`
`

`

`Case: 22-1822 Document: 54 Page: 6 Filed: 03/26/2024
`
`6
`
`BOYER v. US
`
`plaintiff may counter that the affirmative defense is merely
`pretextual. See, e.g., Ryduchowski v. Port Auth. of N.Y. &
`N.J., 203 F.3d 135, 142 (2d Cir. 2000) (citing Belfi v. Pren-
`dergast, 191 F.3d 129, 136 (2d Cir. 1999)).
`The government conceded that Dr. Boyer had estab-
`lished a prima facie case under the Equal Pay Act because
`Dr. Boyer and the male comparator performed work of sim-
`ilar skill, effort, and responsibility under similar working
`conditions for unequal pay. But the government argued
`that the pay differential was justified by a “factor other
`than sex,” namely Dr. Boyer’s prior salary. Dr. Boyer in
`turn contended that the BVAMC violated the EPA by rely-
`ing on prior salary alone to set her and the male compara-
`tor’s disparate salaries. There is no contention that the
`government’s reliance on prior salary was pretextual.
`III
`The Northern District of Alabama initially granted
`summary judgment to Dr. Boyer, finding that “the record
`establishes that prior salary alone was the reason for [the]
`salaries and ‘such a justification cannot solely carry the af-
`firmative defense.’” Boyer v. Wilkie, No. 2:19-CV-00552,
`2019 WL 13268069, at *5 (N.D. Ala. Nov. 5, 2019) (quoting
`Irby v. Bittick, 44 F.3d 949, 955 (11th Cir. 1995)). Thereaf-
`ter, the government filed a motion to dismiss, arguing that
`the district court lacked subject matter jurisdiction, and
`plaintiff filed a motion to transfer the case to the Court of
`Federal Claims (“Claims Court”). The magistrate judge va-
`cated his ruling on summary judgment and transferred the
`case.
`Before the Claims Court, the parties cross-moved for
`summary judgment. The Claims Court concluded that the
`statute allowed consideration of factors other than sex and
`held that consideration of prior pay alone was a factor other
`than sex. In reaching this conclusion, the court relied on a
`pay-setting statute, 5 U.S.C. § 5333, which allows prior pay
`to be considered in hiring. The Claims Court concluded
`
`

`

`Case: 22-1822 Document: 54 Page: 7 Filed: 03/26/2024
`
`BOYER v. US
`
`7
`
`that Congress provided as to federal employees that “exist-
`ing pay alone, without regard to high or unique qualifica-
`tions or other factors, is an appropriate reason to depart
`from the otherwise minimum rate of pay under the GS sys-
`tem.” J.A. 29. The Claims Court also relied on 38 U.S.C.
`§ 7408, containing similar language in a statute governing
`aspects of VA hiring. Because, in the Claims Court’s view,
`prior pay alone could establish an affirmative defense to a
`prima facie case under the EPA in the context of federal
`employees, the court granted summary judgment for the
`government and denied Dr. Boyer’s motion for summary
`judgment. This appeal followed.
`We have jurisdiction under 28 U.S.C. § 1295(a)(3).
`DISCUSSION
`Summary judgment is appropriate if there is no genu-
`ine issue of material fact in dispute and the moving party
`is entitled to judgment as a matter of law. First Com. Corp.
`v. United States, 335 F.3d 1373, 1379 (Fed. Cir. 2003); Rule
`56(a) of the Rules of the Court of Federal Claims (RCFC).
`We review the grant of summary judgment by the Claims
`Court de novo. Id.
`
`I
`This case presents the question whether the rules con-
`cerning consideration of prior compensation should be dif-
`ferent for federal employers as compared to employers
`outside the federal government in light of two federal stat-
`utes that together apply to most, but not all, federal em-
`ployee hiring and that permit consideration of prior pay in
`hiring—5 U.S.C. § 5333 and 38 U.S.C. § 7408. These stat-
`utes do not apply to Dr. Boyer because she was hired pur-
`suant to 38 U.S.C. § 7401(3), a statute that provides
`specifically for the hiring by the VA of certain health pro-
`fessionals (including pharmacists), though the VA Hand-
`book governing such hiring states that “[a]uthorized
`officials may, after considering an individual’s existing pay,
`
`

`

`Case: 22-1822 Document: 54 Page: 8 Filed: 03/26/2024
`
`8
`
`BOYER v. US
`
`higher or unique qualifications, or special needs of VA, ap-
`point . . . VHA GS patient-care personnel at rates of pay
`above the minimum rate.” VA Handbook 5005, Part II,
`Chapter 3 (Dec. 6, 2007). The government argues that, un-
`less one rule is held to be applicable to all federal employ-
`ees, the different statutes would in practice “carve VA
`employees into distinct classes for the purpose of EPA
`claims.” Appellee Br. at 24 (quoting J.A. 34). We agree the
`EPA should apply equally to all federal employees. The
`question here is whether it applies differently to federal
`employees than to employees outside the federal govern-
`ment.
`
`II
`We first consider the standard applicable to employers
`other than the federal government and whether prior com-
`pensation in that context can justify a pay differential.
`A
`The EPA was enacted in 1963. The EPA prohibited
`wage discrimination on the basis of sex for work that re-
`quires “equal skill, effort, and responsibility, and which are
`performed under similar working conditions.” 29 U.S.C.
`§ 206(d)(1). As the Supreme Court long ago made clear,
`“[t]he Equal Pay Act is broadly remedial, and it should be
`construed and applied so as to fulfill the underlying pur-
`poses which Congress sought to achieve.” Corning Glass
`Works, 417 U.S. at 208.
`As noted, the EPA provides for four exceptions justify-
`ing a salary differential between employees of the opposite
`sex, when the differential is made pursuant to “(i) a senior-
`ity system; (ii) a merit system; (iii) a system which
`measures earnings by quantity or quality of production; or
`(iv) a differential based on any other factor other than sex.”
`Id. Here, we are concerned with the fourth exception and
`the question whether prior pay is a factor other than sex.
`
`

`

`Case: 22-1822 Document: 54 Page: 9 Filed: 03/26/2024
`
`BOYER v. US
`
`9
`
`The courts of appeals have adopted three main ap-
`proaches to the use of prior compensation as a “factor other
`than sex” defense to the EPA. 29 U.S.C. § 206(d)(1)(iv).
`The Fourth and the Seventh Circuits have held that prior
`pay is a factor other than sex and that, standing alone, it
`can justify differential treatment. They interpret the
`fourth “catchall” exception to include virtually any factor,
`so long as it is not sex. Wernsing v. Dep’t of Hum. Servs.,
`State of Ill., 427 F.3d 466, 469 (7th Cir. 2005). Because, in
`the Seventh Circuit’s view, “markets are impersonal and
`have no intent,” setting wages based on what the market
`will bear cannot be discriminatory—so the EPA is not vio-
`lated even when prior compensation is the only justifica-
`tion for a wage differential. Id.; see also Spencer v. Va.
`State Univ., 919 F.3d 199, 206 (4th Cir. 2019).
`The remaining circuits that have considered the ques-
`tion have rejected this approach, holding that considera-
`tion of prior pay standing alone cannot be a factor other
`than sex. One circuit, the Ninth, has held that prior pay
`can never justify unequal pay. Rizo v. Yovino, 950 F.3d
`1217, 1229 (9th Cir. 2020). The court found that the pres-
`ence of the first “other” in the phrase “any other factor
`other than sex” limits the word “factor” to considerations
`that are job-related. Id. at 1229. The EPA “requires em-
`ployers to demonstrate that only job-related factors, not
`sex” caused the wage disparities between employees of the
`opposite sex. Id. at 1228. In the Ninth Circuit’s view, “the
`history of pervasive wage discrimination in the American
`workforce prevents prior pay from satisfying the em-
`ployer’s burden to show that sex played no role in wage dis-
`parities between employees of the opposite sex.” Id.
`Therefore, prior pay is excluded as a factor other than sex
`under 29 U.S.C.A. § 206(d)(1)(iv).3
`
`
`In Rizo, the Ninth Circuit describes the difference
`3
`between using prior pay when
`justifying a wage
`
`

`

`Case: 22-1822 Document: 54 Page: 10 Filed: 03/26/2024
`
`10
`
`BOYER v. US
`
`Three circuits have followed a middle ground, allowing
`consideration of prior pay while acknowledging that it may
`perpetuate existing discrimination, and have held that
`prior pay can be a factor other than sex only if it is consid-
`ered together with at least one other permissible factor, for
`example experience or education. See, e.g., Balmer v. HCA,
`Inc., 423 F.3d 606, 612 (6th Cir. 2005), abrogated on other
`grounds by Fox v. Vice, 563 U.S. 826, 832 (2011) (“Consid-
`eration of a new employee’s prior salary is allowed as long
`as the employer does not rely solely on prior salary to jus-
`tify a pay disparity.”); Glenn v. Gen. Motors Corp., 841 F.2d
`1567, 1570–71 (11th Cir. 1988); Irby v. Bittick, 44 F.3d 949,
`955–56 (11th Cir. 1995); Price v. Lockheed Space Opera-
`tions Co., 856 F.2d 1503, 1506 (11th Cir. 1988); Riser v.
`QEP Energy, 776 F.3d 1191, 1199 (10th Cir. 2015).4
`The basic notion behind these cases is an employer has
`shown that a lower rate of prior pay is not serving as a
`
`
`differential under the EPA and relying on prior pay when
`setting an employee’s salary. 950 F.3d at 1231. Some find
`this not to be a meaningful distinction. See id. at 1234
`(McKeown, J., concurring) (“Permitting prior pay in setting
`salary but not as an affirmative defense to the Equal Pay
`Act results in an indefensible contradiction. The ‘tension’
`highlighted by the majority is precisely the reason that
`prior pay cannot be relegated to the dust bin.”).
`4 The Eighth Circuit has permitted the use of prior
`salary only after “carefully examin[ing] the record to en-
`sure that an employer does not rely on the prohibited ‘mar-
`ket force theory’ to justify lower wages” for women. Drum
`v. Leeson Elec. Corp., 565 F.3d 1071, 1073 (8th Cir. 2009)
`(quoting Taylor v. White, 321 F.3d 710, 718 (8th Cir. 2003)).
`“In conducting this examination, this court’s concern is re-
`lated solely to the issue of whether the prior salary is based
`on a factor other than sex.” Id.
`
`

`

`Case: 22-1822 Document: 54 Page: 11 Filed: 03/26/2024
`
`BOYER v. US
`
`11
`
`proxy for sex—and is thus “other than sex,” as required by
`the EPA—when there is a clearly identified other reason
`besides sex (such as less education or less experience). In
`those circumstances, those “business reasons . . . reasona-
`bly explain the utilization of prior salary.” Irby, 44 F.3d at
`955 (alteration in original) (quoting Price, 856 F.2d at
`1506). The concern about relying on prior pay standing
`alone in the case of female hires is that prior pay might be
`artificially reduced by prior sex discrimination such that
`the prior pay would be lower than that for the male com-
`parator and its consideration would improperly justify a
`lower starting salary for an equally qualified female hire.5
`If there are other differences between the two that are truly
`considerations unrelated to sex (education, work experi-
`ence, recommendations, etc.) that favor the male compara-
`tor, it is likely that these same differences could explain
`any prior pay gap as well. Under these circumstances, the
`employer can properly rely on educational, experience, or
`other legitimate, non-sex-based differences and prior pay
`together.
`
`B
`This middle ground approach recognizes that sex dis-
`crimination can be (but is not always) inherent in prior pay.
`As both the government and Boyer acknowledge, the con-
`cern with the use of prior compensation is that prior com-
`pensation itself may be lower because it reflects gender
`discrimination. The concern is well justified. As pointed
`out by amici and not contradicted by the government, “the
`gender wage gap has hardly narrowed over the last 15
`years.” Brief for National Women’s Law Center, et. al. as
`Amici Curiae Supporting Plaintiff-Appellant at 8, Boyer v.
`
`5 The concern about relying on prior pay generally
`arises only if it is used to justify a pay differential, i.e.,
`where the male comparator’s prior pay is higher than the
`female hire’s prior pay.
`
`

`

`Case: 22-1822 Document: 54 Page: 12 Filed: 03/26/2024
`
`12
`
`BOYER v. US
`
`United States (No. 22-1822) (citing Amanda Barroso &
`Anna Brown, Gender Pay Gap in U.S. Held Steady in 2020,
`Pew Research Ctr. (May 25, 2021), https://www.pewre-
`search.org/fact-tank/2021/05/25/gender-pay-gap-facts/).
`“[W]omen working full time, year round were paid just 84
`cents for every dollar paid to men in 2021.” Id. (citing Nat’l
`Women’s Law Ctr., NWLC Resources on Poverty, Income,
`(Sept. 13, 2022),
`and Health Insurance
`in 2021
`https://nwlc.org/resource/nwlc-resources-on-poverty-in-
`come-and-health-insurance/); see also Jessica Semega &
`Melissa Kollar, Income in the United States: 2021, U.S.
`Census Bureau, Current Population Reports, at Table A-7
`(Sept. 2022), https://www.census.gov/content/dam/Cen-
`sus/library/publications/2022/demo/p60-276.pdf. When a
`pay disparity is the result of sex discrimination, using prior
`pay to set compensation necessarily perpetuates unjusti-
`fied pay disparities.
`The government does not dispute—as an empirical
`premise—that reliance on prior pay can perpetuate im-
`proper disparate treatment. It could hardly do otherwise.
`During the pendency of this appeal, the government final-
`ized regulations prohibiting consideration of prior pay
`when setting salary for new employees. Advancing Pay Eq-
`uity in Governmentwide Pay Systems, 89 Fed. Reg. 5737,
`5754–57 (Jan. 30, 2024) (to be codified at 5 C.F.R. pts. 531–
`32, 534 & 930).6 In its rulemaking, the government con-
`ceded, among other things, that “[b]ecause salary history is
`not always a good proxy for worker value, experience, and
`expertise . . . setting pay based on a candidate’s salary his-
`tory could perpetuate a pay rate that [is] inequitable.” Id.
`at 5748.
`
`
`6 This regulation will only apply prospectively. Id.
`at 5737. The rulemaking does not address the question of
`whether the EPA is violated by consideration of prior pay
`alone.
`
`

`

`Case: 22-1822 Document: 54 Page: 13 Filed: 03/26/2024
`
`BOYER v. US
`
`13
`
`Thus, using prior compensation alone could undermine
`a core concern of the EPA—to eliminate gender discrimina-
`tion in compensation. See also id. at 5752 (“21 states and
`22 localities have enacted laws prohibiting the use of salary
`history in setting pay.”). The empirical evidence discussed
`by the government in its proposed rulemaking, which pro-
`posal Dr. Boyer cited in a notice of supplemental authority,
`reflects that when government actors have enacted bans on
`considering prior pay, they have seen increases in women’s
`salaries and decreases in the gap between men and
`women’s salaries—confirming that prior pay may operate
`as a proxy for sex. See Appellant’s Citation of Supple-
`mental Authority, ECF No. 50 (referencing 88 Fed. Reg.
`30251 (May 11, 2023)); see also 88 Fed. Reg. at 30258. In
`the final rulemaking, the government acknowledged that
`“[p]ay setting based on salary history may be inequitable,
`can perpetuate biases from job to job, and may contribute
`to a pay gap between the earnings of men and women.” 89
`Fed. Reg. at 5737.
`In light of these factual premises, relying on prior com-
`pensation alone as an affirmative defense to the EPA risks
`thwarting the Act’s most fundamental goal—equal pay for
`equal work. In short, these empirical premises recognize
`the simple fact that prior pay can be—and frequently is—
`a proxy for the sex of the worker.7 When prior pay is a
`proxy for sex, it is not “other than sex”—it is intertwined
`with sex. The EPA prohibits reliance on prior pay unless
`(1) the prior pay itself is not based on sex, or (2) an addi-
`tional permissible factor “other than sex” is present to as-
`sure a factfinder that the “other factor” of prior pay is
`indeed “other than sex” (i.e., not a proxy for sex).
`
`
`It is significant that these factual points are not
`7
`only undisputed by the government in its briefing and at
`oral argument, but affirmatively advanced by the govern-
`ment in the rulemaking.
`
`

`

`Case: 22-1822 Document: 54 Page: 14 Filed: 03/26/2024
`
`14
`
`BOYER v. US
`
`C
`It follows that because it is undisputed that prior pay
`can perpetuate systemic gender discrimination, the best in-
`terpretation of the phrase “other factor other than sex”
`does not include prior pay alone (unless that prior pay itself
`can be shown to be not based on sex). We are in agreement
`with the Sixth, Tenth, and Eleventh Circuits with this one
`qualification. We think that this approach most conforms
`with the both the text and the underlying central purpose
`of the EPA.
`This middle-ground approach also meets the EPA’s
`goal to accommodate legitimate business interests, partic-
`ularly the requisite flexibility to hire and retain employees.
`See Washington Cnty. v. Gunther, 452 U.S. 161, 171 n.11
`(1981) (“[T]he fourth affirmative defense [was included] be-
`cause of a concern that bona fide job-evaluation systems
`used by American businesses would otherwise be dis-
`rupted.”). Thus, this approach acknowledges that there
`may be legitimate reasons to consider prior salary, such as
`the ability to hire and retain skilled workers, but that prior
`salary without consideration of other factors can allow be-
`havior to persist that is “antithetical to the language and
`purpose of the EPA.” Jennifer Safstrom, Salary History
`and Pay Parity: Assessing Prior Salary History as a “Factor
`Other Than Sex” in Equal Pay Act Litigation, 31 Yale J.L.
`& Feminism 135, 139 (2019).
`We also agree that, as many of our sister circuits have
`held, this exception (consideration of prior pay with other
`non-sex-based factors) is permissible only if that consider-
`ation was in fact the basis for the decision, but not if it is
`offered as an after the fact justification. See Drum v.
`Leeson Elec. Corp., 565 F.3d 1071 (8th Cir. 2009). In Drum,
`the court held that “merely . . . articulating a legitimate,
`non-discriminatory reason” will not allow an employer to
`“escape liability.” Id. at 1072 (quoting Simpson v. Mer-
`chants & Planters Bank, 441 F.3d 572, 579 (8th Cir. 2006)).
`
`

`

`Case: 22-1822 Document: 54 Page: 15 Filed: 03/26/2024
`
`BOYER v. US
`
`15
`
`Instead, “the defendant must prove that the pay differen-
`tial was based on a factor other than sex.” Id. (quoting
`Simpson, 441 F.3d at 579). Similarly, other circuits have
`explained that it is not enough that “the employer’s prof-
`fered reasons could explain the wage disparity.” Riser, 776
`F.3d at 1198 (quoting Mickelson v. N.Y. Life Ins. Co., 460
`F.3d 1304, 1312 (10th Cir. 2006)). It is necessary that “the
`proffered reasons do in fact explain the wage disparity.” Id.
`(quoting Mickelson, 460 F.3d at 1312); see also U.S. Equal
`Emp. Opportunity Comm’n v. Md. Ins. Admin., 879 F.3d
`114, 121 (4th Cir. 2018). Because language of the EPA pro-
`hibits a disparity in pay among genders “‘except where
`such payment is made pursuant to’ one of the four . . . af-
`firmative defenses,” it is not enough to provide a post hoc
`nondiscriminatory reason without evidence that the non-
`discriminatory reason actually motivated the decision to
`set unequal pay. Mickelson, 460 F.3d at 1312 (emphasis
`added) (quoting 29 U.S.C. § 206(d)(1)).
`D
`In short, the central lesson is that the prior pay cannot
`be an “other factor other than sex” if the prior pay itself is
`the product of sex discrimination. In joining the other cir-
`cuits and adopting this middle ground, we think one fur-
`ther qualification is required. It is necessary to leave room
`for an employer to otherwise establish that the prior pay is
`not based on sex. If the employer can establish that prior
`pay was not based on sex, the employer is relying on an
`“other factor other than sex” to justify the disparity. We
`leave for future cases to consider what evidentiary showing
`is needed to carry this burden.
`Both the text of the EPA and precedent require the em-
`ployer to carry the burden of establishing that the prior pay
`was not the product of gender discrimination. Consistent
`with the characterization as an affirmative defense, the
`Supreme Court, our court, and every circuit to expressly
`consider address the question have concluded that the
`
`

`

`Case: 22-1822 Document: 54 Page: 16 Filed: 03/26/2024
`
`16
`
`BOYER v. US
`
`employer bears the burden of establishing the factual
`premises underlying the affirmative defense. See, e.g.,
`Corning Glass Works, 417 U.S. at 196 (stating that once a
`prima facie case has been set out, “the burden shifts to the
`employer to show that the differential is justified under one
`of the Act’s four exceptions”); Moore v. United States, 66
`F.4th 991, 996 (Fed. Cir. 2023) (en banc); Soto v. Adams
`Elevator Equip. Co., 941 F.2d 543, 548 (7th Cir. 1991) (“If
`an EPA plaintiff establishes a prima facie case, the burden
`shifts to the defendant employer to provide evidence of any
`of the statutorily based affirmative defenses . . . .”).
` Thus, the employer bears the burden to prove its af-
`firmative defense that prior pay is a factor other than sex
`because it does not reflect sex discrimination. As we ex-
`plained in Moore v. United States, once a prima facie case
`is established, “it becomes the employer’s burden to prove—
`as an affirmative defense—that the pay differential has a
`permissible non-sex-based justification.” 66 F.4th at 996.
`That burden allocation follows from the plain text of
`the EPA. The EPA requires an employer to show both that
`the pay differential was justified by an “other factor” and
`that such factor was “other than sex.” 29 U.S.C.
`§ 206(d)(1)(iv). Merely showing that an employer relied on
`prior pay—the alleged “other factor”—does not carry the
`full burden imposed by the statute. Id. Instead, the em-
`ployer must also show that the prior pay was not based on
`sex—that it was, in fact, also “other than sex.” Id. As the
`party with the burden of proof, the employer is not entitled
`to simply assume that prior pay is unrelated to (or “other
`than”) sex. Without a showing that the prior pay is a “non-
`sex-based” justification, an employer cannot carry the af-
`firmative defense. Moore, 66 F.4th at 996. This approach
`is simply a faithful application of the requirement that the
`employer must show both the existence of an alleged “other
`factor” and must—as a factual matter—show that it is
`“other than sex.”
`
`

`

`Case: 22-1822 Document: 54 Page: 17 Filed: 03/26/2024
`
`BOYER v. US
`
`17
`
`In summary, the employer can only rely on prior pay if
`either (1) the employer can demonstrate that prior pay is
`unaffected by sex-based pay differentials or (2) prior pay is
`considered together with other, non-sex-based factors.
`III
`The government does not dispute that other circuits
`have held in the context of employers other than the federal
`government that prior compensation alone in general can-
`not be the governing factor. Nor does the government or
`the Claims Court “suggest that other courts have incor-
`rectly construed the EPA as precluding defendants’ reli-
`ance on existing or prior pay alone to justify pay
`differentials between employees of different sexes.” J.A. 30
`n.13. However, the government argues that a different
`rule should prevail with respect to federal government em-
`ployees.
`
`A
`Initially, the EPA applied only to private employees
`and did not apply to federal employees (or state and local
`government employees). The federal government was ap-
`parently excluded as an employer simply because the EPA
`was an amendment to the Fair Labor Standards Act, and
`the government was excluded from coverage when the first
`Fair Labor Standards Act was passed in 1938. S. REP. NO.
`88-176, at 2 (