The very idea of more than a million women taking part in a class-action lawsuit initially filed by several women against Wal-Mart for allegations of sexual bias by Wal-Mart managers — supposedly condoned by company executives at 3,400 stores — must offend Americans with any sense of fairness. If this legal atrocity is permitted to move forward, it could cost Wal-Mart billions, most of which will only serve to make lawyers richer, not plaintiffs.

That’s why arguments heard by the U.S. Supreme Court this week is so important. In what may be the most important business case in more than a decade, our nation’s highest court will judge if this whole business of class-action suits is approaching the point of absurdity, threatening the financial wellbeing of all businesses, when cases of alleged bias might be far more judiciously decided on a studied case-by-case basis.

Is true justice not best rendered under such conditions? Where is the justice, we ask, in lumping up to a million or more women into one lawsuit, especially when their circumstances may each be different, may even involve elements of wrongdoing by the plaintiffs themselves rather than just the accused? Can Wal-Mart really be accused of a policy of widespread sexual discrimination in so many cases and at so many stores when it has, coincidentally, a long-standing anti-discrimination policy?

This is what the high court must decide. A suit filed against Wal-Mart by a handful of women in 2001 was structured to include any women who worked for Wal-Mart or Sam’s Club since 1998. Last year, a sharply divided Ninth Court of Appeals decided the suit could proceed as a gargantuan class-action suit for more than a million women, even though five dissenting judges said such a suit, based on such hugely variable evidence, would be unwieldy.

We know some companies, big and small, and their managers, qualified or ill-chosen, exercise bias against women employees, denying them better wages, promotion, even dignity in the workplace. All Americans should condemn such practices. Companies should feel the heat when such cases come to light. But class-action suits that include millions of people, who may or may not have suffered such indignities or wrongs, can hardly be conducive to American justice.

Wal-Mart officials don’t deny they may have bad managers. With 1.4 million employees across the nation, many of them managers, it’s only natural some will exercise poor judgment. Companies should work overtime to address this problem, perhaps harder than they do. But officials correctly contend such suits should be judged individually on the unique merits of the case.

It’s time for our highest court to fine-tune what criteria should be embraced in such cases. We don’t rule out the legitimacy of class-action suits on occasion, but their employment in the courts should be narrow in focus and more than obvious to all. That’s not the case here.