"Do you know who the firm that you employ for civil rights is?" Beatty asked.

Beatty, who is the chair of the Financial Services Diversity and Inclusion Subcommittee, grilled Zuckerberg on a number of topics related to race, diversity and civil rights. She asked about Facebook's contracting of minority or women-owned firms, allegations that Facebook's ad systems allowed housing discrimination , and the company's on-going civil rights audit, which is being conducted by Relman Dane & Colfax , a Washington D.C. civil rights law firm.

Facebook CEO Mark Zuckerberg has talked a lot about civil rights this week. But when Rep. Joyce Beatty, D-Ohio, asked him for details during a congressional hearing on Wednesday, Zuckerberg did not have many answers.

"How could you not know when you have employed the most historical, the largest civil rights firm to deal with issues that are major, and this is what's so frustrating to me. It's almost like you think this is a joke when you have ruined the lives of many people, discriminated against them," Beatty said.

Beatty used her time during a hearing that was focused on Facebook's libra cryptocurrency project to emphasize Facebook's checkered past with minorities. The company has been accused of having a "black people problem" by a former employee, and it's been accused of censoring black people by users.

"Do you know what the percentage of African Americans are on Facebook in comparison to majority folks? Do you know what the percentages are?" Beatty asked.

"People using the Facebook?" Zuckerberg responded.

"Yes. Do you know what the percentages are for African Americans?" Beatty asked.

"I don't because we don't collect the races of people," Zuckerberg said.

"Well it came out in a report in the Pew Research Center that was sent to you. So maybe you just don't read a lot of things that deal with civil rights or African Americans," Beatty said.

Zuckerberg spoke about Facebook's civil rights audit in his prepared remarks for his testimony before the House Financial Services Committee on Wednesday. He also talked about civil rights during a speech on free expression on Thursday at the Georgetown University, invoking civil rights leaders Frederick Douglass and Martin Luther King Jr. to explain why Facebook will not fact-check political ads. Zuckerberg's remarks were criticized by Bernice King, the daughter of King Jr.

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"I have a lot of questions I'm going to send to you that I'm not going to be able to get through, and I would like an answer because this is appalling and disgusting to me," Beatty told Zuckerberg.

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