But five of the justices also responded "no" to the broader question of whether there were "questions of law or fact common to the class" - and that opinion will make it much more difficult for litigants to combine their efforts in suing powerful corporations.
Justice Antonin Scalia, writing for the majority, said the women couldn't provide a common answer to the crucial question: "Why was I disfavored?" He also noted that Wal-Mart has an explicit anti-gender-discrimination policy and that local store managers have great discretion when making employment decisions.
Scalia said there was no apparent "glue" to hold together the women's claims, so they could not become a class. "It is quite unbelievable that all managers would exercise their discretion in a common way without some common direction," Scalia wrote.
His view completely ignores the "common direction" made obvious in the statistics presented as evidence of a nationwide discrepancy in the wages of men and women employed by Wal-Mart.
For example, female workers in 2001 were paid up to 37 cents less per hour than their male counterparts. Female managers earned about $14,500 less annually. And while women were 92 percent of Wal-Mart's cashiers, they were only 14 percent of its store managers.
The majority opinion also ignores the impact of biases in the minds of people in supervisory positions when they are not effectively addressed by an employer. A policy against gender discrimination is meaningless if the company doesn't take effective steps to uphold it.
The statistics showed clearly that Wal-Mart didn't do enough to prevent gender discrimination, choosing instead to let store managers decide how fair their employment practices would be.
Instead of ruling on those facts, the court has made it harder for individuals who alone may not be able to afford legal representation to pool their resources under the tent of a class-action complaint. Wal-Mart, as a result, gets away with having an antidiscrimination policy, but not enforcing it.