US senators have called on Facebook CEO Mark Zuckerberg to "show leadership" and appear before them to face accusations made against his company.
Former product manager turned whistleblower, Frances Haugen, told a committee hearing on Tuesday that Facebook repeatedly prioritised profits over user safety.
She said she felt compelled to come forward because "almost no one outside of Facebook knows what happens inside Facebook". Haugen has suggested the platform courts controversy on its news feed to keep users engaged and online for longer in order to sell more targeted advertising, which is its primary revenue source.
Despite Haugen attracting considerable media coverage in the lead up to the testimony, Zuckerberg initially avoided commenting on the issue, and instead posted a video of himself on a sailing trip. This appeared to anger Senator Richard Blumenthal.
"Mark Zuckerberg ought to be looking at himself in the mirror today, and yet, rather than taking responsibility and showing leadership, Mr Zuckerberg is going sailing," said Blumenthal during the testimony.
"No apologies, no admission, no action, nothing to see here. Mark Zuckerberg, you need to come before this committee, you need to explain to Francis Haugen, to us, to the world and to the parents of America what you were doing and why you did it."
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Zuckerberg did finally respond in the hours after the testimony, posting on his personal Facebook page to say that "many of the claims don't make any sense". However, the CEO's comments didn't appear to address many of the claims made by Haugen, such as the algorithm change on its news feed which she suggested promoted more controversial content.
"If we didn't care about fighting harmful content, then why would we employ so many more people dedicated to this than any other company in our space - even ones larger than us?" Zuckerberg wrote.
"If we wanted to hide our results, why would we have established an industry-leading standard for transparency and reporting on what we're doing? And if social media were as responsible for polarising society as some people claim, then why are we seeing polarisation increase in the US while it stays flat or declines in many countries with just as heavy use of social media around the world?"
Haugen was called "a 21st century American hero" by Senator Ed Markey, who also warned that the committee would be coming for Mark Zuckerberg. However, Blumenthal said it was "premature" to consider a subpoena for Zuckerberg, adding that his appearance before Congress should be "voluntary".
"He has a public responsibility to answer these questions," he said.
