Betty Dukes, the woman who led a class-action civil rights lawsuit against Walmart that reached the Supreme Court in 2011, has died at age 67. As the Associated Press reports, Dukes passed away on July 10 at her home in Antioch, and she had been working for Walmart up until last year.

Dukes was the lead plaintiff in the case, Dukes v. Wal-Mart Stores Inc., which first reached federal district court in San Francisco in 2001. She argued that after six years of working for the chain she had been denied training and the ability to get promoted, and that Walmart systemically paid women less than their male counterparts, and promoted men at faster rates. The case sought to represent all 1.6 million female employees of the store chain, making it the largest gender bias class-action lawsuit in U.S. history.

The case was affirmed twice by the Ninth Circuit Court of Appeals, however divided panels of judges repeatedly split over whether the plaintiffs' class could be certified — given the wide variability of the 1.6 million plaintiffs' circumstances.

The Supreme Court in 2011 would later rule unanimously that the class could not be certified as comprised, however they split in a 5-4 decision over whether the class action could proceed in some other form, with the conservative end of the court siding with Walmart's attorneys and prevailing. The case was therefore dismissed, and Betty Dukes continued working for Walmart for another five years.

Justice Scalia wrote for the majority that the plaintiffs' evidence, which relied heavily on statistics and talk of the corporate culture, was too weak and "worlds away from ‘significant proof’ that Wal-Mart ‘operated under a general policy of discrimination.’ ”

The New Yorker's Jeffrey Toobin wrote of the case at the time, "The conservatives on the Roberts Court have a well-earned reputation for hostility to civil plaintiffs of all kinds, and especially those who raise civil-rights claims. But it’s worth noting that there was a good degree of ideological agreement in this case — that there are some things simply beyond the abilities of our federal courts. And cases with a million plaintiffs are among them."

Dukes established a small foundation, the Betty Dukes Foundation, that accepted donations to help her activism in the cause of the betterment of the lives of marginalized workers.

Walmart has repeatedly come under fire over low wages, poor treatment of workers, and lack of adequate health insurance for its staff. Though Dukes's lawsuit was ultimately unsuccessful, Walmart was forced to settle 63 separate lawsuits in 2008 related to wage violations in 42 states.

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