Joseph M. Sellers, head of the Civil Rights and Employment practice group at Cohen Milstein, shared his experience working on Dukes v. Wal-Mart Stores, the largest civil rights class action suit in the United States.

Sellers, who is representing a class of more than 1.5 million female employees at Wal-Mart stores in an ongoing sexual discrimination lawsuit, detailed the progress of the case and fielded questions from Harvard Law School students at the talk, hosted by the Harvard Women’s Law Association on April 19, 2011.

The Supreme Court heard oral argument in the case in March, and Sellers said he believes the justices will need to be convinced that Wal-Mart’s corporate culture is responsible for gender discrimination in the company’s personnel practices.

“There were questions during the argument about how you convey bias in the workplace, particularly gender bias,” Sellers said. “They asked, how can you assure us the managers were influenced in some way by the corporate culture?”

Wal-Mart is alleged to have discriminated against women in promotions, pay, and job assignments in violation of the Civil Rights Act of 1964. The case was brought forward in 2000 when a 54-year-old Wal-Mart employee in California named Betty Dukes filed a sex discrimination claim, alleging that she was denied the training she needed to advance to a higher paying position despite six years of employment and excellent performance reviews.

“Gender stereotypes are not unlawful—everybody uses stereotypes,” Sellers said. “What makes it unlawful is managers making decisions based on those stereotypes, and women are consistently underpaid and promoted more slowly than men with the same qualifications.”

Watch the video of Sellers’ talk.

Sellers said his firm investigated the claims and interviewed female Wal-Mart employees across the country for about a year before taking on the case.

“We learned through remarkably similar accounts by many women who reported that when they asked about pay raises, they were told such things as men are better managers, women are better off staying home and taking care of the family, men see their jobs as a career, and women are here as a hobby,” Sellers said.

The firm found statistically significant disparities between male and female employee salaries across the country at every level. Additionally, women took twice as long as men to reach manager status.

“Our contention is the company expects managers to follow the corporate culture that includes gender stereotypes, so the managers often exercise discretion consistent with those stereotypes, making women worse off than similarly qualified men.”

Sellers joined Cohen Milstein Sellers & Toll PLLC in 1997 and has represented victims of discrimination and other illegal employment practices individually and through class actions, including Beck. v. Boeing Company, which included a class of more than 28,000 women employees at Boeing facilities in Washington state alleging sex discrimination in pay and overtime decisions and Conway, et al. v. Deutsch, which included a class of all female undercover case officers at the CIA alleging sex discrimination in promotions and job assignments.

Sellers has also testified more than 20 times before committees of the United States Senate and House of Representatives on various civil rights and employment issues and worked on the passage of the Civil Rights Act of 1991, the Americans with Disabilities Act of 1990, and the Lily Ledbetter Fair Pay Restoration Act of 2009. He served on the Clinton/Gore Transition Team in 1992 and 1993.

Sellers received a J.D. from Case Western Reserve School of Law in 1979 and a B.A. in American History and Literature from Brown University in 1975.