Wal-Mart, the nation's largest private employer, operated thousands of stores nationwide with a corporate policy that delegated substantial discretion over pay and promotions to local managers. A proposed nationwide class of approximately 1.5 million current and former female employees alleged systemic sex discrimination in violation of Title VII, contending that decentralized discretion operated against a backdrop of a strong and uniform corporate culture that permitted gender stereotyping. Plaintiffs offered statistical analyses showing disparities in pay and promotions between men and women, anecdotal declarations from female employees across multiple regions, and expert social framework testimony suggesting that a large, discretionary system could foster biased outcomes absent safeguards. They sought injunctive and declaratory relief, as well as backpay, and moved to certify a class under Rule 23(b)(2). The district court certified the nationwide class, and the Ninth Circuit largely affirmed. Wal-Mart petitioned for certiorari, arguing that plaintiffs failed to establish commonality under Rule 23(a)(2) and that backpay claims were improperly certified under Rule 23(b)(2).
1) Whether the proposed nationwide class of female employees satisfied Rule 23(a)(2)'s commonality requirement where alleged discrimination arose from local managers' discretionary pay and promotion decisions. 2) Whether claims for backpay may be certified under Rule 23(b)(2), which is designed for injunctive or declaratory relief applicable to the class as a whole.
Class certification requires satisfaction of Rule 23(a): numerosity, commonality, typicality, and adequacy. For Rule 23(a)(2) commonality, plaintiffs must show not merely common questions, but a common contention capable of classwide resolution such that its truth or falsity will resolve an issue central to the claims of each member in one stroke. Courts must conduct a rigorous analysis, which may overlap with the merits, to determine whether Rule 23 is met. Under Rule 23(b)(2), certification is appropriate when the party opposing the class has acted or refused to act on grounds that apply generally to the class, making uniform injunctive or declaratory relief appropriate; individualized monetary claims that are not incidental to such relief generally cannot be certified under Rule 23(b)(2). A class action may not abridge a party's substantive rights under the Rules Enabling Act, and Title VII entitles a defendant to individualized determinations and defenses regarding backpay.
The Supreme Court reversed class certification. The proposed class failed to satisfy Rule 23(a)(2) commonality because plaintiffs did not identify a common contention whose determination would resolve a central issue for all class members. In addition, claims for backpay could not be certified under Rule 23(b)(2) because such monetary relief is not incidental to injunctive or declaratory relief and would deprive Wal-Mart of its right to individualized defenses. The Court also rejected the use of trial by formula to adjudicate backpay.
Commonality: The majority, per Justice Scalia, emphasized that commonality requires more than the existence of shared questions; it requires a unifying glue capable of generating common answers. Plaintiffs identified only a general policy of delegating discretion to local managers, which is the opposite of a uniform discriminatory policy. Showing that thousands of managers across thousands of stores exercised discretion in a discriminatory manner requires proof that the company operated under a general policy of discrimination. The offered evidence did not supply the necessary glue. The expert social framework testimony was too theoretical and did not identify a specific companywide discriminatory mechanism. Plaintiffs' statistical evidence masked significant regional variation and did not isolate the cause of disparities to a uniform corporate practice. The anecdotal evidence, though not irrelevant, was too sparse relative to the enormous class size and unevenly distributed across regions. Without a common contention whose resolution would determine liability in one stroke for all class members, Rule 23(a)(2) was not satisfied. Rigorous analysis and merits overlap: The Court reiterated that certification demands a rigorous analysis and may require probing into the merits insofar as they overlap with Rule 23 requirements. It signaled skepticism that expert opinions can be insulated from reliability scrutiny at the certification stage, indicating that courts may apply Daubert principles when assessing whether expert evidence credibly supports commonality. Rule 23(b)(2) and monetary relief: The Court unanimously held that claims for individualized monetary relief such as backpay do not fit within Rule 23(b)(2) because that subdivision is tailored for indivisible injunctive or declaratory relief. Backpay would require individualized determinations and would foreclose Wal-Mart's entitlement under Title VII to present individualized defenses, such as performance-based reasons for pay or promotion decisions. The Court rejected the proposed trial by formula approach that would have statistically sampled a subset of claims and extrapolated liability and backpay to the class, holding that such a procedure would abridge the defendant's rights and contravene the Rules Enabling Act and Title VII's requirement for individualized proceedings. Separate views: Justice Ginsburg, joined by three Justices, agreed that backpay could not be certified under Rule 23(b)(2) but would have found Rule 23(a)(2) commonality satisfied on the record and would have remanded for consideration of certification under Rule 23(b)(3), which provides for damages classes with predominance, superiority, and class notice and opt-out rights.
Dukes tightened the commonality requirement, insisting on a cohesive, classwide issue that can be resolved in one stroke. It authorized courts to examine merits-related evidence at certification and encouraged reliability screening of expert proof. The decision sharply limits the use of Rule 23(b)(2) for claims involving monetary relief and bars trial by formula that strips defendants of individualized defenses. Practically, plaintiffs now more often pursue narrower, tailored classes, bring claims under Rule 23(b)(3) with damages and predominance showings, or use subclasses tied to specific policies or decision-makers. For law students, Dukes is foundational for understanding how Rule 23 shapes litigation structure, evidence, and strategy.
Wal-Mart v. Dukes is a watershed in class certification doctrine. It reframed commonality as a demanding inquiry that requires proof of a unifying classwide contention and invited courts to rigorously examine the evidence, even when that examination overlaps with the merits. The Court also confined Rule 23(b)(2) to true injunctive or declaratory relief and prohibited statistical shortcuts that impair individualized defenses.