The US Supreme Court throws out one of the biggest ever class action lawsuits, a sex discrimination case against Walmart. Channel 4 News hears what this means for US law - and society.

Walmart sex discrimination class action thrown out (Getty)

The judges ruled that more than one million female employees of Walmart could not proceed in the lawsuit, accusing the supermarket giant of paying women less and giving them fewer promotions.

The Supreme Court agreed with Walmart's argument that the employees, working in different roles at 3,400 different stores nationwide, did not have enough in common to be grouped together in a single lawsuit. It also agreed that the class action certification violated federal rules for such lawsuits.

Walmart hailed the decision as a major victory. "We are pleased with today's ruling and believe the court made the right decision. Walmart has had strong policies against discrimination for many years," it said in a statement.

Walmart has had strong policies against discrimination for many years. Walmart statement

The company's shares were up 18 cents to $53.02 in late trading yesterday, after rising as much as 1.3 per cent earlier in the day.

Gisel Ruiz, a company executive vice president, said the ruling effectively ended the class action lawsuit, and Theodore Boutrous, Walmart's lead attorney in the case, added: "This decision will have a significant impact on other class actions."

Read more: the background on the Walmart sex discrimination class action

Impact on other class actions?

But a leading expert on class action lawsuits in the United States told Channel 4 News this was unlikely to be the case. Samuel Issacharoff, Reiss Professor of Constitutional Law at New York University, said the case was of "secondary significance" for class action lawsuits.

He said: "The bulk of US class actions have moved to questions of financial impropriety. So the kind of case that Walmart represents is a very, very small minority of class action practice."

It is a tremendous achievement of American law that that kind of impediment to the advancement of disadvantaged people in the United States has largely been eradicated. Expert Professor Samuel Issacharoff

But he said the judges' decision to throw out the case did mark a major evolution for American civil rights law, and society.

The modern class action suit was largely used as a push for civil rights integration after the 1964 Civil Rights Act, Professor Issacharoff explained.

"The firm-wide class action corresponds to systemic discrimination at a broad institutional level. But employers no longer simply discriminate on a basis of sex or race - there are no longer signs that say 'blacks or women need not apply'.

"I think it is a tremendous achievement of American law that that kind of impediment to the advancement of disadvantaged people in the United States has largely been eradicated."

Paradox

Professor Issacharoff admitted it was a "paradox" that because "times have changed and the law has changed", this type of lawsuit was no longer the best way for these women to bring their discrimination case. But he said that they were still able to bring their lawsuits individually, and challenge decisions at local or regional levels.

The lawyer for the women who sued Walmart, Joseph Sellers, said they were now considering options including smaller class action suits or proceeding individually.

The woman whose case began the showdown, Betty Dukes, said: "We still are determined to go forward and we still are determined to present our case in court and I believe that we will prevail there."

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