WASHINGTON – The Supreme Court on Monday accepted what will likely become the highest-profile business case next year, agreeing to decide whether 1.5 million female employees of Wal-Mart can pursue job discrimination claims in the largest employment class-action suit in the country’s history.

The court accepted Wal-Mart’s appeal of a decision by the U.S. Court of Appeals for the 9th Circuit in California that the suit could go forward.

The case will be heard in the spring.

The justices will not decide the merits of the claims first filed by six women in 2001. It will be looking at the question of whether a single suit is proper when alleging charges of pay discrimination and lack of promotions spread across thousands of stores in every region of the country.

That decision could be as important as the veracity of the claims, and business groups and civil rights activists are squaring off over the implications of a case.

Business groups say certification of a class action puts enormous pressure on a company to settle regardless of whether the charges can be proved, because of the cost of the litigation and the potential award at stake. In the case of Wal-Mart, the nation’s largest employer, the amount could be billions of dollars.

But civil rights groups say class actions are the most effective way of making sure a business ends discriminatory practices and pays a price for its actions.

Theodore Boutrous, lead counsel for Wal-Mart, said Monday in a statement, “We are pleased that the Supreme Court has granted review in this important case. The current confusion in class action law is harmful for everyone – employers, employees, businesses of all types and sizes, and the civil justice system.”

Laywers for the women said they were “confident that the court will agree that the women of Wal-Mart are entitled to their day in court.”

The case began in 2001, when lawyers sued on behalf of six current and former female employees led by Betty Dukes, a Wal-Mart greeter in Pittsburg, Calif.

They represent more than 1.5 million women who worked at Wal-Mart and Sam’s Club stores since December 1998.

Lawyers for the women told the Supreme Court that a district judge granted the class-action suit after hearing expert evidence that showed both salaried and hourly female employees received lower pay and fewer promotional opportunities than men, and that Wal-Mart has uniform management and personnel policies across its thousands of stores.