F OR P UBLICATION



### UNIT E D ST AT E S CO URT O F APPE AL S FO R T H E NINT H CIRCUIT

J U A N I T A S T O C K

W E L L ; M I C H

A E L L E W I S ; V I N C E N E E S O N ; G U I L L E R M O L

. A M I G O ; E. R. B A L I N T O N ; N I K O L A U S B O R T H N E ; E D W

A R D B R O W N E ; P E T E R B U S A L

A C C H I ; S I L V I A D A V I D ; P H I L I P F L E C K ; S E V E R O F L O R E S ; G E O R

G E F O G A R T Y ; M A L C O L M F O N G ; M A R Y G O D F R

E Y ; J A S O N H U I ; J A C K

L Y N M. J E H L ; R I C H A R D J U E ; R O B E R

T L E U N G ; P A U L L O Z A D A ; D.H. B U

D M A S S E Y ; B R

U C E M E A D O R S ; T H O M

A S O’ C O

N N O R ; S U S A N R O L O V I C H ; J E S S I E W A S H I N G T O N ; M I C H

A E L W E L L S ; G A R Y C A S T E L ; B A R

T H O L O M E W J O H N S O N ; M I K

E B O L T E ; J O N E S J A M E S , Plaintiffs-Appellants
,

v

.

C I T Y A N D C O U N T Y O F S A

N F R A N C I S C O , Defendant-Appellee

. N o. 12-15070

D.C. No. 4:08-cv-05180- PJ H

OPI NI ON

A ppeal from the United States District Court for the Northern District of California Phy llis J . Hamilton, District J u dg e, PresidingS T O C K W E L L V

. C I T Y & C N T Y

. O F S A N F R A N C I S C O 2

Arg ued and Submitted September 10, 2013—San F rancisco, California

F iled April 24, 2014

B efore: J . Clifford W allace, Ray mond C. F isher, and Marsha S. B erz on, Circuit J udg es.

Opinion by J udg e B e rz on

SUMMARY *

F ed. R. Civ. P . 23(f

) Class Certif

ication

The panel in an interlocutory appeal reversed the district court’s denial for want o f commonality of a request u n d er F ed. R. Civ. P. 23(f) for certification of a class composed of certain San F rancisco Police Department officers.

The p anel held that the district court abused its discretion in deny ing c lass certification because of i t s l eg al error o f evaluating merits questions, rather than f ocusing o n whether th e questions presented, whether meritorious or not, were

common to the members of the putative class. The panel h eld that g iven the interlocutory nature of the app e al, and its

c onsequent limitation to class certification factors only
, t h e panel c o u l d not consider the merits q uestions, even as an alternative g r ound for affirmance. The panel remanded to the di strict c ourt to consider in the f irst instance whether the

* T h is su m m ary co n stitu

tes n o part o f th e o p in io n o f th e co u rt. It h as b een p rep ared b y

co u rt staf

f f o r th e co n v en i en ce o f

th e read er.S T O C K W E L L V

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. O F S A N F R A N C I S C O 3

putative class satisfied the strictures of Rule 23(b)(3), as w ell as the other prerequisites for class certification.

COUNSEL

Michael S. Sorg e n (arg

ued), Andrea A dam B rot t , a n d Ry an L . Hicks, L aw Offices of Michael S. Sorg en, San F rancisco, California; and Richard A. Hoy er, Hoy er and Associates, San F rancisco, California, for Plaintiffs-Appellants.

Christine Van Aken (arg

ued), Deputy City Attorney
, Dennis J

. Herrera, City Attorney
, Eliz abeth Salveson, Chief L abor Attorney
, and J onathan C. Rolni c k
, D e puty City Attorney
, City of San F rancisco, Sa n F rancisco, California, for Defendant-Appellee.

OP INION

B ERZ ON, Circuit J udg e :

Several San F rancisco police o fficers (“the plaintiffs” or “the o f ficers”) over the ag e o f f

orty perf o rmed w ell enoug h

on an ex amination in 1998 to qualify for conside r a t i o n for
pro m o tion to Assistant I nspector. They alleg e that a new policy of t h e San F r ancisco Police D epartment (“SF PD”) abando n i n g the ex amination as a basis for certain assig nments

w o r ked a disparate impact based on ag e. The plainti ff s soug h t certification of a class composed of all SF PD officers over forty who had qualified on the 1998 ex a mination.

The d istrict cou r t denied certification for want o f commonality

. W e permitted the officers to a ppeal the denialS T O C K W E L L V

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of class certific a t i o n under F ederal Rule of Civil Procedure 23(f), and now reverse, holding improper the district court’s reliance on merits issues unrelated to the p e r tinent commonality

inquiry

.

I.

Nearly three and a half d ecades ag o, the Civil Service Commission o f the City and County of S a n Francisco (“City ”) entered into a consent decree to settle alleg a tions o f employ ment discrimination in the SF PD on the basis o f race,

sex , and national orig in, in violation of Title VI I of the Civil Rig hts Act of 1964, 42 U.S.C. § 2000e et seq

.

I n late 1998, the district c o u rt terminated that consent decree. B y st ipulation of the parties, however, the district
court r e t ained jurisdiction over issues related to a recently administered promotional ex amination — the Q-35 Assistant I nspector ex amination for promotion to t h e I nvestig ations B ureau — which the p arties ag r eed would be g overned by the
terms of the consent decree. On the s a m e d ay , the district
court issued an order outlining promotion proced u res for officers who had sat for the Q-35 Ass i stant I nspector

ex a mination. That order required a minimum o f 175 A s sistant I nspector a

p pointments from the list of police officers who had passed the ex a mination, arrang ed in order o f

ex a m performance (“Q-35 L ist”). The first 110 p romotions

were to be made in rank order of p erformance. S ubsequent appointments, the c o urt ordered, “will be made from a sliding band that will start at rank 1 11. The b and width is 84 points.” The district court a u t h oriz e d the City to review v arious “secondary criteria” when making selections within t h at sliding band. B etween 1998 and 2006, the City selected 229S T O C K W E L L V

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police officers from the Q-35 L ist for p romotion to Assistant I nspector.

I n 2005, the Chief of Police a n n ounced a c hang e in promotion policy : To improve operational flex ibility and rationaliz e the promotional prog ression, the SF PD w ould no long er promote Assistant I n s p ectors to the I nvestig ations B ureau from the Q -35 L ist. I nste a d
, the SF PD would administer a new Q-50 Serg eants ex amination a nd assig n

some newly promoted Serg e a nts, selected on the basis of their performance on the new ex am, to the I nvestig ations B ureau. Those Serg eants assig ned to the I nvestig ations B ureau would have duties previously assig ned to Assistant I nspectors.

The City administer e d the Q-50 Serg eants Ex amination in 2006 and created a list of elig ible officers (“Q-50 L ist”) the following y ear. Soon thereafter, the SF PD beg an promoting Serg e ants from the recently compiled Q-50 L ist, many o f whom were g iven investig ative duties. A ssistan t Chief Morris T abak ag reed, in a deposition taken in t h i s case, that he knew of no reason “that those appointments could n ot have been made from the Q -35 list[ ] that resulted from the 1998

ex a m.”

The officers initially filed this a ct i o n in late 2008, alleg ing that SF PD’s decision to use the Q-50 list instead o f the Q-35 list f

or investig ative assig nments both constituted a pattern or practice of discrimination and g enerated a disparate impact on older offic e r s in v iolation of the Ag e Discrimination in Employ ment A c t ( “ADEA”), 29 U .S.C. §§ 6 2 1 –634. They also alleg ed p arallel violations o f California’s F air Employ ment a n d H ousing Act (“F EHA”), Cal. Gov’t Code §§ 12940–12951.S T O C K W E L L V

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The officers subsequently soug ht certification of a class under their F EHA disparate impact claim. The district court denied the motion for certification, ex plaining t h a t the officers f ailed to satisfy t h e requirements of both F ederal Rules of Civil Procedure 23(a)(2) and 23(b)(3).

After denial of certification, the officers filed a S econd Amended Complaint alleg ing o nly a disparate impact theory of liability
, ag ain under both the ADEA and F EHA. Several months later, the officers re n e wed their motion for class certification of the F EHA claim, 1 proposing as the class to be certified SF PD “officers who were ag ed forty a nd older as o f each of the d a tes of the challen ge d a ppointments in 2007, 2008, and 2 0 09 and who could have been appointed to investig ative positions had the City properly made appointments from the Q -35 L ist.” The putative class defined

an officer “who could have been appo i n t e d
, ” as an officer within the 84-point selection band at the time SF PD assig n ed

a serg eant to investig ative work. The off i c er s f urther proposed the creation o f separate subc l a sses for those w ho could have b een appointed at each dat e

. C ertification was soug h t u nde r R u l e 23(b)(3). As the common question required for c ertification, F ed. R. Civ. P. 23(a)(2), the officers asserted a common q

uestion of fact: “[ W] het h er the City ’s employ ment practi c e of a

ppointing Serg eants ex clusively from the Q-50 L ist to investig a tive positions traditionally performed b y A ssistant I nspectors and refusing to make any

1 T h e o f f i cers also so u g h t “ co n d itio n al certif icatio n ” o f a co llectiv e actio n u n d er t

h e A DEA o n th e g ro u n d th at 29 U.S.C. § 2 1 6 (b ), w h ich
g o v ern s co llectiv e actio n s u n d er th e A D EA
, req u ires a lesser sh o w in g to

au th orize ag g reg ate l itig atio n

. Fo r th e pu rp o ses o f th is ap p eal, th e o f f icers h av e f o rf eited th at claim b y f

ailin g t o a r gu e it in th eir b rief s

. S ee, e.g

. , Drea m Ga mes o

f Ariz., In c. v. PC On site
, 5 6 1 F.3 d 9 8 3
, 9 9 4 –9 5 (9 th Cir. 2 0 0 9 ).S T O C K W E L L V

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. O F S A N F R A N C I S C O 7

of the appointments from the active Q-35 L ist, had a disparate impact on qualified applicants for the investig ative positions who were ag ed f

orty or above at the time of those appointments, in violation of F EHA.”

The distri c t court d enied the renewed motion f or class certification for want of commonality

. Having disp osed o f the motion on that g round, the district co urt ex pressly declined to rule on the officers’s arg ument that the p utative

c lass satisfied the requirement of Rule 23(b)(3), w h i c h requires both that common questions “predominate over any questions a ffecting only individual members” of the class a nd “that a class action is superior to other available methods for fairly and efficiently adjudicating the controversy .”

The officers timely soug ht p e rmission to appeal under Rule 23(f), w hich authoriz es d is c retionary review of an interlocutory order g ranting or deny ing class certif i ca tion. See F ed. R. Civ. P. 23(f); see also Chamberlan v. Ford Motor Co.
, 4 02 F .3d 952, 959 (9th Cir. 200 5 ) ( per curiam) (describing t h e s t andards we employ to g uide our discretionary authoriz ation of appeals under Rule 23(f)). This Court g ranted permission for the appeal, a n d t h e officers timely perfected it. See F ed. R. App. P. 5(d).

II.

F ederal Rule of Civil Procedure 23(a)(2) conditions class certification on demonstrating that members of the proposed class share common “question s of law or fact.” Such commonality is one o f f o ur “threshold requirements” contained in Rule 23(a ) ; the o ther three are numerosity
,S T O C K W E L L V

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t y picality
, and adequacy of representation. 2 S ee, e.g. , Amchem Prods., Inc. v

. W i n d sor , 521 U.S. 591, 613 (1997). Tog ether, these requirements seek to “limit the class c laims
to those fairly encompassed by the named plaintiff’s claims.” W al-Mart Stores, Inc. v. Dukes
, 131 S. Ct. 2541, 2550 (2011) ( quoting Gen. Tel. Co. of Sw. v. Falcon
, 457 U.S. 14 7
, 1 5 6 (1982)) (internal quotation marks omitted).

W al-Mart instructed that, althoug h Rule 23(a)(2) r efers to

common “ questions of law or fact” in the plural, “‘[ e ] ven a sing le [ common] question’ will do.” Id. at 2556 (alterations in orig inal) (quoting id. at 2566 n.9 ( G i n s burg
, J
., dissenting )). W e h ave since clarified “that R u le 23(a)(2)
req u i res

. . . ‘a sing le significant question of law or fact.’” Abdullah v. U.S. Sec. Assocs., Inc.
, 731 F .3d 952, 9 57 ( 9 th Cir. 2013) ( emphasis in ori ginal) (quoting Mazza v. A m

. Honda Motor Co. , 666 F .3d 581, 589 (9th Cir. 2012)).

2 T h e tex t o f

th e su b sectio n is as f o llo w s:

(a) P rereq u isites. On e o r m o re m em b ers o f a class m ay

su e o r b e su ed as rep resen tativ e p arties o n b eh alf o f all

m em b ers o n ly if :

(1 ) th e class is so n

u m ero u s th at j o in d er o f all m em b ers is im p racticab le;

(2 ) th ere a r e q u estio n s o f l aw o r f act co m m o n t o th e class;

(3 ) t h e claim s o r d ef

en ses o f th e rep resen tativ e p arties are ty p ical o f th e claim s o r d ef

en ses o f th e class; an d

(4 ) th e rep resen tativ e p arties w ill f airly an d ad eq u ately
p ro tect th e in terests o f

th e class.

Fed . R. Civ . P . 2 3 (a).S T O C K W E L L V

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Rule 23(a)(2) is not “a mere pleading standa r d
, ” so establishing commonality sometimes requires affirmative evidence, w hich the courts must subject to “ r ig orous analy sis.” W

al-Mart
, 1 3 1 S. Ct. at 2 551 ( quoting F a lcon
, 457 U.S. at 161). Such rig or often “will entail some overlap with the merits of the p laintiff’s underly ing claim.” Id. W h ile some evaluation of t h e m e r its frequently “cannot be helped” in evaluating commonality
, id.
, that likelihood o f overlap with the merits is “no license to eng ag e in freerang ing merits inquiries at the c e rt i f ication stag e.” Amgen Inc. v

. Conn. R e t

. P l a n s & Trust Funds
, 133 S. Ct. 1184, 1194–95 (2013). I nstead, as the Supreme Court clarified last
y ear, “[ m] erits questions may be considered to the ex tent — but only to the extent — that they a re relevant to d etermining whether the Rule 23 p re r e quisites for class certification a re

sa t i s fi e d.” Id. at 1195 (emphasis added). “[ W ] hether class members could actually prevail on the merits of their claims” is not a p roper inquiry in determining t h e p r eliminary question “whether common questions ex ist.” Ellis v

. Costco W holesale Corp. , 657 F .3d 970, 983 n.8 (9th Cir. 2011).

F urther, a common contention need not b e one that “will be answered, o n the merits, in f a v o r o f the class.” Amgen
, 133 S. Ct. at 1191. I nstead, it only “must be of such a nature that it is capable of classwide resolution — which means that determination of its truth or falsity will resolve an issue that is central to the v a l i d ity of each one of the claims in o ne stroke.” W

a l

- M art , 131 S. Ct. at 2551 (emphases added). “To hold otherwise would turn class certification into a minitrial” o n the merits, Ellis
, 6 5 7 F. 3 d at 983 n.8, when the
purpose o f class certification is merely “to select the metho[ d] best suited to adjudication of the controversy fair l y a n d efficiently
, ” Amgen
, 1 33 S. Ct. at 1191 (alteration in orig inal) (internal quotation marks omitted).S T O C K W E L L V

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A m g e n , published o v er a y ear after the d istrict cou r t decision here, illustrates well the a pplication of the principle
t h a t demonstrating commonality does n o t require proof t h at the p u tative class will prevail on whatever common questions it identifies. I n Amgen
, a class alleg e d securities fraud under § 10(b) of the Securities Ex chang e Act o f 1934, 48 Stat. 891,

as a mended, 15 U.S.C. § 78j(b), and Securities and Ex chang e Commission Rule 10b–5, 1 7 C.F .R. § 240.10b–5. 133 S. Ct.
at 1191. To succeed on the merits, plaintiffs a l l e g ing securities f

raud under Rule 10b–5 “must prove ‘(1) a material misrepresentation or omission by the defendant; (2) scienter; (3) a connection between the misrepresentation o r omission and the purchase or sale of a secur i ty ; (4) reliance upon the misrepres entation or omission; (5) economic loss; a nd (6) loss causation.’” Id. a t 1192 ( quoting Matrixx Initiatives, Inc. v. Siracusano
, 131 S. Ct. 1309, 1 317 (2011)) ( i n ternal quotation marks omitted). The fraud-on-the-market doctrine “permits certain Rule 10b–5 plaintiffs to invoke a rebuttable presumption of reliance on material misrepresentations aired
to the g eneral public,” when those misrepresent a t i o n s concern securities traded in an efficient market

. Id. T o invoke the f r a u d

- o n

- t h e

- m a r k e t p r e s u m p t i o n , “ p l a i n t i f f s m u s t demonstrate that the alleg e d m isrepresentations were publicly known

. . . , that the stoc k t r a d e d in an e fficient market,

. . . that the relevant transaction took place ‘between the time the misrepresentations w er e m ade and the time the truth was revealed,’” Erica P

. J

ohn Fund, Inc. v. Halliburton Co.
, 131 S. Ct. 2179, 2185 (2011) (quoting Basic Inc. v. L e v i n s on , 4 8 5 U

. S

. 2 2 4
, 2 4 8 n

. 2 7 (1 988)), and t h a t t h e misrepresentations were material, A mgen , 133 S. Ct. at 1195.

Amgen held that w here a class of investors seeks to rely

on the fraud-on-the-market presumption, proof of materiality is unnecessary to certify a class under Rule 23(b)(3 )

. I d. atS T O C K W E L L V

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1191. The reasoning
, in part , was that “[ t] he alleg ed misrepresentations a

nd omissions, whether material o r immaterial, would be so equally for all investors composing the class.” I

d. at 1191. I f the factfinder ultimately held those representations immaterial, that d etermination would not amount to “some fatal dissimilar i t y among class members that would make use of the class-action device inefficient o r unfair. I nstead, [it would g enerate] a fatal simi l a r i t y

— failure of proof as to an element of t h e plaintiffs cause o f action.” I

d

. a t 1197 (emphases added) (alteration omitted) (quoting Richard A. Nag areda, Class Certification in the Age of Aggregate Proof

, 84 N.Y.U. L

. Rev. 9 7, 10 7 ( 2009)) (internal quotation marks omitted). B y its very nature, such

a similarity
, whe t h e r fatal or n ot to the merits of the materiality issue, is a common question. Althoug h pro of o f

ma teriality was “ an essential predicate of the fraud-on-themarket theory ,” id. at 1195, the court held it “properly addressed at trial or in a ruling on a summary -judg ment motion,” id. at 1197.

Notably
, A mgen concerned satisfaction of Rule 23(b)(3), which requires not merely a common question b u t also “find[ ing ] that the questio n s o f l a w or fact common to class members predominate over any questions affecti n g o nly individual members.” I t held pro o f o f a factor that would ultimately b e e s s e n tial to success on the class’s claims not merely unnecessary to demon s t rate commonality
, but also

un n ecessary to demonstrate that such commonality predominates

. Rule 2 3 ( b ) (3) imposes a “far more demanding ” standard than 2 3(a)(2). Amchem
, 5 2 1 U.S. at 624. I t w as the less demanding standard of Rule 23(a)(2) that

was the basis of the d is t r ict court’s denial of c ertification here.S T O C K W E L L V

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The principle that courts must consider merits issues only

as necessary to determine a p ertinent Rule 23 factor, and not otherwise, has special force at the appellat e l evel where, a s here, we review a class certification determination under Rule 23(f). Under Rule 23(f), the limitation on consideration o f the merits to the relevant c lass certification questions i s o f jurisdictional sig nificance. Rule 23(f) permits discretionary
, interl o cu t o ry a

ppeals “from an order g ranting o r deny ing class-action certification.” F ed. R. Civ. P. 23(f). I nterlocut o r y appeals are, of c o urse, “the ex ception rather than the rule.” Chamberlan
, 402 F .3d a t 959. Absent Rule 23(f) or some other applicable ex ception, o ur j urisdiction would be constrained by “‘the g e neral rule that a p arty is entitled to a sing le appeal, to be deferred until final judg ment has been entered.’” Mohawk Indus., Inc. v. Carpenter
, 558 U .S. 100, 106 (2009) (quoting D i g i t a l Equip. Corp. v

. Desktop Direct, Inc.
, 511 U.S. 863, 8 68 (1994)); see also 28 U.S.C. § 1291. As the ex ception to the final judg ment rule created b y Rule 23(f) applies o n ly to c l ass c ertification decisions, merits inquiries unrelated to certif i c ation ex c eed

our limited Rule 23(f) jurisdiction, a s well as the needs o f Rule 23(a)–(b). I

n contrast, were this an appeal from a final judg ment a fter a class was certified (or n ot certified) and the merits then determined, we would have the option o f addressing the me ri t s and, if we decided to hold ag ainst the plaintiffs, not addressing the class certification question. W e must p olice the bounds o f our jurisdiction vig o rously here a s elsewhere, see, e.g. , Crowley v. Bannister
, 734 F .3d 9 6 7, 974 (9th Cir. 2013), and so may not ourselves venture into merits issues unnecessary

to the Rule 23 issue before us.S T O C K W E L L V

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. O F S A N F R A N C I S C O 13

III.

W ith th a t backg r ound, we reach the only question properly before us — whether the district court’s denial o f the officers’s motion for cl a s s certification was an abuse o f discretion. See Ellis
, 6 5 7 F .3d at 980. An “error of law[
, ]

. . . . ‘reliance on an improper factor,

. . . o m i s s i o n o f a substantial factor, o r

. . . a clear error of judg ment in w e ig hing the correct mix o f f

a ct ors’” qualifies as a

n abuse o f discretion. Bateman v. Am. Multi-Cinema, I nc. , 623 F .3d 708, 712 ( 9th Cir. 2010) (quoting In re W ells F a r g o M o r tg. Overtime Pay Litig.
, 571 F .3d 953, 957 (9th Cir. 2009)). W e conclude tha t the district court erred in deny ing class certification because of its l eg al e rror of evaluating merits questions, rather than focusing on whether the questions presented, whether meritorious o r not, were common to the members of the p utative class. B y doing so, the district court made an error of law and relied on improper factors, thereby abusing its discretion.

To assess whether the putative c l a s s members share a

common question, the a

n swer to which “will resolve an issue that is central to the validity of each on e o f the [ class members’s] claims,” we must identify the elements of t he class members’s case-in-chief. W al-Mart
, 131 S. Ct. at 2551. The requisite prima facie case for a disparat e

- i m p a ct ag e discrimination cla i m under California’s F EHA is parallel to t hat under the ADEA. See Katz v. Regents of th e Un i v

. o f Cal.
, 2 29 F .3d 831, 835 (9th C i r

. 2 0 0 0 ); see a lso Clark v

. Claremont Univ. Ctr.
, 6 Cal. App. 4th 639, 666 (1992). Under b o t h statutes, “a plaintiff must d emonstrate ‘(1) the

occurrence o f certain outwardly n e u tral employ ment practices, and (2) a sig nificantly adverse or disproportionate impact o n p ersons of a p articular [ a g e] p r oduced by theS T O C K W E L L V

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employ e r’s facially neutral acts or practices.’” Katz
, 229 F .3d
at 835 (alteration in o r i ginal) (quoting Palmer v

. United States
, 794 F .2d 534, 538 ( 9th Cir. 1986)). This formulation requires a plaintiff to “‘isolat[ e] a n d identify [ ] the specific employ ment practices that are alleg edly responsible for any observed statistical d isparities.’” Smith v. City of Ja c k s o n , 544 U

. S

. 228, 241 ( 2005) ( emphasis in orig inal) (quoting W ards Cove P acking Co. v

. A tonio
, 4 90 U.S. 642, 656 (1989)). The plaintiff must also demonstrate a causal connection between those specific employ ment practices a

nd the asserted impact o n those of a particular ag e

. S e e , e.g. , Lewis v. City of Chicago
, 560 U

. S. 205, 212 (2010); Katz
, 229 F .3d at 836. 3

Here, the officers have ide n t i f ied a sing le, wellenunciated, un iform policy that, alleg edly
, g enerated all the d i sparate impact o f w hich they c o mplain: the SF P D ’s decision to make investig ative a ssig n ments using the Q-50 L ist instead o f the Q -35 L ist. Each membe r of the p utative

3 T h e A DEA co d if

ies “ f i v e af f i rm ativ e d ef

en ses” at 2 9 U.S.C. § 6 2 3 (f ). Mea ch a m v. Kn olls Ato mic Po wer La b.
, 5 5 4 U.S. 8 4
, 9 1 (2 0 08 ) (q u o tin g Tra n s Wo r l d A irlin es, In c. v. Th u rsto n , 4 6 9 U.S. 1 1 1
, 1 2 2 (1 98 5 )) (in t ern al q u o t atio n m ark s o m i tted ). A n em p lo y er is n o t l i ab l e, f

or

ex am p le, f o r o t h e r w i se- pro h ib i ted actio n s “ w h ere ag e i s a b o n a f

id e

o ccu p atio n al qu alif

icatio n reaso n ab ly n ecessary to th e n o rm al o p eratio n

o f th e p a r t i cu lar b u sin ess, o r w h ere th e d if

f eren tiatio n is b ased on

reaso n ab le f

acto rs o th er th an ag e

. . . .” 2 9 U.S.C. § 6 2 3 (f )(1 ); see a l

so 2 9 U.S.C. § 6 2 3 (f

) (listin g o th er d ef

en ses). T h e FEHA also co n t a i n s

a f f i rm ativ e d ef

en s es f o r, in ter alia, “ b o n a f id e o ccu

p ati o n a l
q u alif icatio n [s]” an d em

p lo y m en t actio n s b ased o n b u s i n ess n ecessity

. Cal. Go v ’ t Co d e § 1 2 94 0 ; Cal. Co d e Reg s. tit. 2 , § 1 1 0 1 0

.

T h e a v ailab ility of su ch d ef en s es, h o w ev er, is n o t p ertin en t t o th e

co m m o n ality q u estio n , as lo n g as th ere is a co m m o n q u estio n as to th e

o f f icers’ s p rim a f

acie case o f

d isp arate im

p act ag e d iscrim in atio n

.S T O C K W E L L V

. C I T Y & C N T Y

. O F S A N F R A N C I S C O 15

c l a s s was on the Q-35 L ist. Each suffered the effects of i t s elimination, whatever those were.

“I dentify ing a specific practice is not a trivial burden” in
ag e discrimination cases alleg ing disparate i m p act. Meacham , 554 U.S. a t 1 01. I ndeed, the first Supreme Court

case to recog niz e the viability of a disparate- i m pact theory under the ADEA rejected the claim on the merits for “failure
to identify the specific practice being challeng e d ,” a mong other shortcoming s. S

mith
, 5 44 U.S. at 241. Requiring plaintiffs to name a specific employ ment practice “has b ite,” Meacham
, 554 U.S. at 100, both o n the m e r i t s and for
purposes of determining whether there is a common question in a disparate impact ca s e

. H ere, the putative class is

c h a l l e n gi n g a sing le employ ment practice: m a k i n g investig ative assig nments from the Q-50 L ist instea d o f t he Q-35 L ist.

Once a specific practice is identified in a disparate impact case, the n ex t

— althoug h not the only — question becomes whether that practice had a d ispropo r t i o n ate adverse impact

on otherwise e l i g i b le officers over forty

. “ Generally disparate impact analy sis is u sed in a class action, but it may also form the basis of an individual c laim.” Bacon v. Honda of Am. Mfg., Inc.
, 370 F .3d 565, 5 76 (6th Cir. 2004); see also W atson v. Fort W

orth Bank & Trust
, 4 8 7 U

. S

. 977, 983 (1988) (addressing an individual disparate imp a ct claim); Pottenger v. Potlatch Corp. , 329 F .3d 740, 749–50 (9th Cir. 2003) (same). I n w hatever p rocedural g uise a disparate impact c laim appears, the party asserting it must demonstrate

a statistical disparity affecting members of the protectedS T O C K W E L L V

. C I T Y & C N T Y

. O F S A N F R A N C I S C O 16

g roup. Absent such a

g roup-based disparity , the claim fails, whether it is articulated by an individual or a class. 4

The officers p r oduced a s t a tistical study purportedly showing a disparate impact. The district court, a nd the City
, critiqued that study as inadequate for

— among other reasons

— failing to conduct a reg r ession a naly sis to take account o f altern a t i v e ex planations, unrelated to ag e, for any statistical imbalance. B ut whatever the failing s of the class’s statistical analy sis, they affect every c lass member’s c laims uniformly
, just a s the materiality issue in Amgen affected every class member uniformly

. Each member of the p u t ative class suffered the e f

f e c t s of eliminating the Q-35 L ist. 5 I f those

4 T h is f eatu re o f d i sp arate im

p act an aly sis d i stin g u ish es it sh arp ly f ro m th e th eo ry o f d isp ar a t e treatm en t. Disp arate im p act an aly s is ad d resses itself “ to th e co n s e q ue n c e s of em p lo y m en t p ractices, n o t sim

p ly th e

m o tiv atio n .” Grig

g s v. Du ke Po wer Co

. , 4 0 1 U .S. 4 2 4
, 4 3 2 (1 9 7 1 ). Su ch d iscrim in ato ry co n seq u en ces are p ercep tib l e o n ly in th e ag g reg ate, w h ich is w h y w e req u ire statistical ev id en ce. B y co n trast, th e cru x o f a d isp arate treatm en t case is th e su

b j ectiv e mo tiva tio n f

or an ad v erse em

p lo y m en t d ecisio n

. A lth o u g h statistical ev id en ce can su p p o rt a disp arate t

reatm en t

c l a i m , as in th e p attern

- or- p ractice cases o f t h e ty p e ad d ressed by Wa l

Ma r t , su ch ev id en ce is o n ly “ pro b ativ e o f m o tiv e,” u sed f o r t h e p u rp ose

o f “ creat[in g ] an in f

eren ce o f d iscrim in ato ry in ten t w ith resp ect t o th e in d ivid u a l emp lo ymen t d eci s i o n at i ssu e.” Ob r ey v. Jo h n so n , 4 0 0 F.3 d 6 9 1
, 6 9 4 (9 th Cir. 2 0 0 5 ) (em ph asis ad d ed ) (q u o tin g D i a z v. Am. Tel. & Tel. , 7 5 2 F.3 d 1 3 5 6 , 1 3 6 3 (9 t h Cir. 1 9 8 5 )).

5 Co n trary to t

h e C i t y ’ s arg u m en t, th at is tru e w ith resp ect t o th ose

m em b ers w h o to o k an d su cceed ed o n th e n ew Q- 5 0 ex am in atio n , as th ey lo st th e sam e p ro m o t io n al o p p o rtu n ity as th eir p eers, reg ard less o f w h eth er th eir s u b s eq u en t a c t i o n s en t itled th em to sim ilar — b u t n ot id en tical

— p ro m o t io n al o p p o rtu n i t ies. W h eth er th o se in d i v id u als w ill b e p reclu ded f ro m o btain in g an y

relief b ecau s e o f

th eir p ro m o tio n s b ased o n th e Q- 5 0

ex am in atio n is a s ep arate q u estio n , as is th e im p act o f th at q u estio n o n th e Ru le 2 3 (b )(3 ) an aly sis to b e co n d u cted o n rem an d
, see in

fra P art IV.S T O C K W E L L V

. C I T Y & C N T Y

. O F S A N F R A N C I S C O 17

effects amount to a disparate impact on a ccount of ag e, it will be so for all c lass members or for none; their claims r ise a nd fall tog ether.

That the City primarily rel i e s o n Katz for its contrary arg ument reveals the fallacy o f its position. Katz considered
not class certifi c ation but a n already certified class’s appeal of an adverse judgment on the merits . 229 F .3d at 833.

I n Katz
, a class of laboratory employ ees claimed the decision to off

er certain early retirement incentives to participants in the University of California Retirement Plan, whose averag e ag e was 5 5
, a nd not to participants in the Public Employ ee Retirement Sy stem, whose averag e ag e was 60, g enerated a dispa r a t e impact on the basis of ag e. Id. at 833–34. W e affirmed the di s t r i ct c ourt’s judg ment a s a matter of law ag ainst the plaintiffs, reasoning they had “ failed
to demonstrate causation,” insofar a s their statistical evidence

was “insufficient to raise an inference that the disparate impact fell upon employ ees by virtue o f their membership in

a protected ag e g roup.” Id. at 836. Th e failure to produce statistics sufficient to d emonstrate a c ausal relationship between employ ee ag e a nd employ er practice defeated the claims of the entire class.

The same will b e true h e re — the statistical showing o f disparate impact due to the c halleng ed policy w i ll either succeed as to the class as a whole or, as the City arg ues, fail

— ag ain, with respect to the class as a w hole. I n hig hlig hting the questions of statistical p roof of disparate impact a nd causation, the City has streng thened, not weakened, the case for c ert i f i c a t i on, as it has identified a common question, the resolution of which will uniformly affect all members of the class. And whether there is a disparate impact on the p utativeS T O C K W E L L V

. C I T Y & C N T Y

. O F S A N F R A N C I S C O 18

class, to be established throug h statistical proof, is “a sing le significant question of

. . . f a c t , ” A b dullah
, 731 F .3d at 957 (emphasis in orig inal) (internal quotation marks omitted), the resolution of which is “central to the validity ” of each of the class members’s claims, W al-Mart , 131 S. Ct. at 2551.

The City o ffers v a rious reasons the putative c lass, o r various members of it, m a y not prevail, including : the decision not to use the Q-35 L i s t a f fected a ll officers on the list e qually
, without r eg ard to ag e ; all the officers on the Q-35 L ist could have taken the Q-50 ex amination, so there was no detrimental impact o n t hem from the p olicy chang e ; there

were no appointments of any A ssistant I nspectors from 2007
t h r o u g h 2009, so the Q-35 L ist was inapplicable during th at period; and many of the class members would not have been promoted even if the Q-35 L ist were used, as there would not have b een enoug h positions for all o f them. Any and all o f these c onsiderations may prove pertinent to the merits of the
case, and possibly to whether c ommon issue s p redominate under Rule 23(b)(3). B u t they d o not eliminate the sig nificant

common question we have identified, however that question is ultimately answered and whethe r or n ot other, individual questions are later determined to predominate.

I n short, the officers are all ch a l l e n ging a sing le p olicy they contend has a dver s el y affected them. The question whether the p olicy has a

n impermissible disparate impact on the basis o f ag e necessarily h as a sing le answer. To so

r e cog n iz e is in no way to approve of the statistical show i n g the offic er s h a v e made as adequate to make out their merits

case. Nor d o es identify ing a common question sufficient for Rule 23(a)(2) purposes entail any disag reement with the City ’ s contention that proper statistical analy sis would neg ate any disparate impact traceable to ag e — or, for that matter, toS T O C K W E L L V

. C I T Y & C N T Y

. O F S A N F R A N C I S C O 19

p r ejudg e a

ny other arg ument or defense the City may o ffer

. The defects the City has identified may well ex ist, b ut they g o to the m e r its of this case, or to the p redominance question,

see infra Part I V. G iven the interlocutory nature of t h is appeal, and its consequent limitation to class certificat i o n factors only
, we may not consider the merits questions, even as an alternative g

round for affirmance.

IV.

Having disposed o f the officers’s certification motion for
want o f commonality
, the district court ex pressly declined to evaluate the puta tive class’s a rg ument that it satisfied the predominance and superiority r equirements of Rule 23(b)(3). The City now conte nds that “individual questions will predominate with respect to [ the officers’s] claims including : (a) whether an officer took the 2006 Serg eants e x a m o r not; (b) comparisons of individual rank on and between the 1998 Assistant I nspector list and the 2 0 07 Serg eant l ist; ( c ) the relative qualifications of each officer o n the list; and, (d) other factors affecting an assig nment to the I nvestig ations B ureau.” The City may or may not be correct. B ut those questions, a s they affe ct predominance, have been inadequately b ri e f

ed here. They h ave no effect on

c o m m o nality
, because there is a sing le, log ically p rior,

common question: whether the cancellation of the Q -35 L ist
g enerated a disparate impact on older officers.

The effect of the q

uestions the City r a i s es on the predominance inquiry are best addressed by the district court, which is “ ‘in the best p osition t o c onsider the most fair a nd efficient procedure f

or conducting any g iven litig ation,’ Doninger v. Pac. N.W

. Bel l, Inc.
, 564 F .2d 1 304, 1309 (9th Cir. 1977), a

nd so must be g iven ‘wide discretion’ to e valuateS T O C K W E L L V

. C I T Y & C N T Y

. O F S A N F R A N C I S C O 20

s uperiority [ under Rule 2 3(b)(3)]
, Lerwill v. Inflight Mot i o n Pictures, Inc.
, 582 F .2d 507, 512 (9th Cir. 1978).” Bateman
, 623 F .3d at 712 (citation forma t ting in orig inal). W e thus REMAND to the district c o urt to consider in the first instance whether the putative clas s s a t i sfies the strictures of Rule 23(b)(3), a s w e ll as the other prerequisites for class certification.

V.

W e REVERSE the district court’s denial of certification for want of commonality

. That determination was an abuse of discretion, as it disreg arded the e x istence of common questions of law and fact and imp ermissibly addressed the merits of the class’s claims.

REVERSED and REMANDED.