As a result, even the numbers the retailer is using to defend its case are extraordinary. The company’s lawyers have said that choosing whether or not to grant class action status (the decision before the Supreme Court is just that—not if Wal-Mart discriminated or not) should be decided on more than just “statistics, sociology, and anecdotes.” Some 90 percent of the company’s 3,400 stores at the time of a lower court’s decision, Wal-Mart has rebutted, do not have statistically significant differences in male and female employees’ pay.

That infers, however, that pay differences do or could exist at 10 percent of its stores. That might be a small ratio, but at Wal-Mart, even small percentages yield eye-popping numbers. Ten percent of its stores means that 340 locations may have had differences in pay; 10 percent of the women in question is still potentially 100,000 people.

Even though that number is actually high, Wal-Mart seems more focused on fighting the class action status of the case than the impression that there is any discrimination going on at its stores.  While the company has said that the anecdotes, such as meetings being held at a Hooter’s restaurant or an employee being told she didn’t get the same raise as her male colleague because he had a family to support, do not reflect company practices or policies, it has also blamed any pay differences on decisions made at the local level.

The company may be wise to fight the first battle first, trying to avoid the class action and defend its practices at the corporate level. The numbers at stake are just that big. As are the consequences: More than 20 other major corporations have filed briefs in support of Wal-Mart, and in fear that a Supreme Court decision in favor of the plaintiffs could open the floodgates for similar class actions.

Still, if the company is not careful, the impression left on many people may not be the one Wal-Mart wants. Discrimination may happen every day in big companies; but even if its presence is minor, it remains a major issue companies should work to stamp out entirely. No matter their size.

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