Kamala Harris grills Facebook’s Mark Zuckerberg for deflecting Senate questions: ‘You don’t have answers’
Sen. Kamala Harris (D-CA) and Facebook CEO Mark Zuckerberg.

Facebook founder and CEO Mark Zuckerberg was grilled by his own United States senator during a marathon public hearing on Capitol Hill Tuesday.

Sen. Kamala Harris (D-CA), the former Attorney General of the most populous state, began by lecturing the billionaire over his failure to answer important questions during hours of testimony.

"I have to tell you, I am concerned about how much Facebook values trust and transparency," Sen. Harris warned. "During the course of this hearing, these last four hours, you have been asked several critical questions for which you do not have answers."

"Those questions have included whether Facebook can track users' browsing activity even after the user has logged off of Facebook, whether Facebook can track your activity across devices even when you are not logged into Facebook," she listed. "Who is Facebook's biggest competition?"

"Facebook, and I'm going to assume you personally as a CEO, became aware in December 2015 that Dr. Kogan and Cambridge Analytica misappropriated data from 87 million users," the former prosecutor noted. "That is 27 months ago, you became aware 27 months ago."

"A decision was made not to notify the users," Harris continued. "Were you part of a discussion that ... resulted in a decision not to inform your users?" Harris asked.

"I do not remember a conversation like that," Zuckerberg replied.

The two went back and forth on an issue.

"Senator, in retrospect, I think we clearly view it as a mistake that we did not inform people," Zuckerberg admitted. "We did that based on false information, we thought the case was closed and the data was deleted."

"There was a decision made not to inform the users, is that correct?" Sen. Harris asked.

"Yes," Zuckerberg answered. "In retrospect, I think that was a mistake. Knowing what we know now, we should have handled things differently."