Facebook Inc. Chief Executive Mark Zuckerberg returned to Capitol Hill on Wednesday where he faced a sometimes confrontational House Energy and Commerce Committee that challenged the tech executive's positions on user privacy, political bias and regulation.
The rapid-fire inquiry contrasted with Zuckerberg's more languid hearing Tuesday before the Senate Commerce, Science and Transportation Committee, and Judiciary Committee.
"Facebook failed its customers," Rep. Raul Ruiz (D-Calif.) said about Facebook's mishandling of user data in the Cambridge Analytica scandal. "We have a responsibility to figure out what went wrong here."
When it was over, Zuckerberg offered little new information, other than revealing he was among the up to 87 million Facebook users who unwittingly had their personal information harvested by Cambridge Analytica. And there was little consensus as to whether Facebook needed to be regulated or left to police itself.
"We need your help here. I don't want Congress to have to act," said Rep. E.L. "Buddy" Carter (R-Ga.). "Please."
The 33-year-old billionaire repeatedly deployed the same tactics he used the previous day with members of the Senate.
When asked if he'd support a specific piece of regulation, Zuckerberg said he was open to exploring it. When pressed about how an open platform can stop more hate speech and fake accounts, he implored patience for the development of more artificial intelligence tools. And when confronted with details about the scope of Facebook's data collection, he promised to get back to the committee.
"I will talk to my team and follow up," Zuckerberg told Rep. Debbie Dingell (D-Mich.) in response to heated questions about how much Facebook tracks internet users on other websites.
Unlike the Senate, where members were allotted five minutes to question Zuckerberg, the House committee granted members four minutes. That gave Zuckerberg less time to meander and he was often interrupted by committee members determined to make their points before time ran out.
"I don't have time for a long answer," said Rep. Anna G. Eshoo (D-Menlo Park), unsatisfied with Zuckerberg's response to a question about when Facebook knew that Cambridge Analytica was harvesting its data to build voter profiles.
The committee also asked pointed questions about the spread of prescription painkillers on the social network.
"Your platform is still being used to circumvent the law and allow people to buy highly addictive drugs without a prescription," said Rep. David McKinley (R-W.Va.). "With all due respect, Facebook is actually enabling an illegal activity, and in so doing, you are hurting people. Would you agree with that statement?"
"I think that there are a number of areas of content that we need to do a better job policing on our service," Zuckerberg responded.
Another line of questioning examined the implications of Facebook's growing political advertising business.
Rep. John Sarbanes (D-Md.) asked if Facebook offered the Trump campaign stronger assistance than the Clinton campaign by providing an embedded sales staff.
Sarbanes cited statistics that showed the Trump campaign placed 5.9 million ads on Facebook in the run-up to the election while the Clinton campaign placed 66,000.
"Can you say with absolute certainty that Facebook or any of the Facebook employees working as campaign embeds did not grant any special approval rights to the Trump campaign?" Sarbanes asked.
Zuckerberg said Facebook offered the same services to both campaigns. But Sarbanes expressed concern that Facebook was acquiring too much political influence.
"I'm worried that that embed program has the potential to become a tool for Facebook to solicit favor from policymakers and that creates the potential for real conflict of interest," Sarbanes said. "A lot of Americans are waking up to the fact that Facebook is becoming sort of a self-regulated superstructure for political discourse."
Conservative members of the committee raised concerns about political bias, particularly in Facebook's news feed algorithm. The company has been accused of suppressing right-wing points of view in the past. Facebook eliminated many news curator positions after they were accused of filtering out conservative topics in a trending news feature.
A popular example of bias cited Wednesday was the banning of Trump supporters Lynnette Hardaway and Rochelle Richardson, better known as Diamond and Silk.
"Facebook called them unsafe to the community. That is ludicrous. They hold conservative views. That isn't unsafe," said Rep. Joe L. Barton (R-Texas).
Rep. Marsha Blackburn (R-Tenn.) said, "Diamond and Silk is not terrorism."
And Rep. Billy Long (R-Mo.) brought out a poster of the conservative bloggers and read a question on their behalf: "What is unsafe about two black women supporting President Donald J. Trump?"
"Congressman, nothing is unsafe about that," Zuckerberg said.
Zuckerberg had announced earlier in the hearing that the ban of Diamond and Silk was made by mistake and that the pair would be reinstated.
Long asked Zuckerberg what became of Facebook's predecessor, Facemash — a "hot or not" site that allowed users to compare the attractiveness of people in side-by-side photos.
A bemused Zuckerberg said the site was a prank, which he developed in his Harvard dorm room 15 years ago.
"There was a movie about this, or said it was about this; it was of unclear truth," Zuckerberg said, referring to the unflattering portrayal of him in the 2010 film "The Social Network." "It has nothing to do with Facebook."
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2:35 p.m. This article was updated after the conclusion of the hearing.
9:35 a.m.: This article was updated with an exchange between Facebook CEO Mark Zuckerberg and Rep. John Sarbanes.
9:10 a.m.: This article was updated with an exchange between Zuckerberg and Rep. Jan Schakowsky.
8:20 a.m.: This article was updated with comments from Rep. Michael Burgess.
7:50 a.m.: This article was updated with Zuckerberg revealing that his own data was among the personal information obtained by Cambridge Analytica.
7:35 a.m.: This article was updated after testimony began.