Three former or current Wal-Mart employees brought suit against Wal-Mart as representatives of one of the largest class action suits in history. Members of the class action included 1.5 million current or former female employees of Wal-Mart Stores, Inc. alleging Title VII violations and discriminatory practices based on their gender. Specifically, the Plaintiffs allege that Wal-Mart's promotion and employment procedures are discriminatory towards women and favorable towards men; generally men are paid more and receive more promotions than women of the same employment levels.
The question for the Court was whether this class action fully complies with the requirements of Rule 23 of the Federal Rules of Civil Procedure. There are four requirements a class action suit must meet under Rule 23: numerosity, commonality, typicality, and adequate representation. The 5-4 opinion written by Justice Scalia centered around the "commonality" requirement and whether the 1.5 million women involved could prove that there are "questions of law or fact that are common to the class." Justice Scalia suggested that the commonality requirement required much more than multiple violations of the same provision of law by Wal-Mart. Rather, all members of the class action must have suffered the same injury. The plaintiffs were trying to "literally sue about millions of employment decisions at once." According to the Court,
"without some glue holding the alleged reasons for all those decisions together, it will be impossible to say that examination of all the class members' claims for release will produce a common answer to the crucial question why was I disfavored."
To prevent an over-encompassing class action claim, the Court noted that the Plaintiffs would have to provide "significant proof" that Wal-Mart "operated under a general policy of discrimination." The only proof offered by the Plaintiffs was expert testimony which claimed there was a social culture at Wal-Mart that makes it vulnerable to gender bias. The expert could not say how regularly stereotypes or discrimination play a role in the decision-making processes. Without more specific evidence, the Court ruled that this was not significant proof and held that the class action was not in compliance with Rule 23.