Zuckerberg hearing : Facebook CEO says firm is in 'arms race' with Russia and is working with Mueller election probe - as it happened

Data abuse scandal threatens to harm the social network forever

Mark Zuckerberg hearing: 'It was my mistake. And I'm sorry.'

Facebook founder and CEO Mark Zuckerberg faced more than five hours of questions from the joint Senate Commerce and Judiciary committees over the privacy and the use of citizen's data..

The long-awaited showdown – one of the first times that Mr Zuckerberg has spoken publicly since a data scandal hit – saw nearly half the US Senate, 44 legislators, interrogate Mr about an issue that threatens to permanently damage the site he co-founded.

Mr Zuckerberg agreed to testify in Congress after revelations that Cambridge Analytica, a data-mining firm affiliated with Donald Trump's presidential campaign, was sold access to personal information from 87 million Facebook users. Cambridge Analytica denies any laws were broken

In his testimony, Mr Zuckerberg disclosed that his company is “working with” special counsel Robert Mueller in the federal probe of Russian interference in the 2016 presidential campaign — and working hard to change its own policies.

“We didn't take a broad enough view of our responsibility, and that was a big mistake," he said. "It was my mistake, and I'm sorry. I started Facebook, I run it, and I'm responsible for what happens here.”

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Mr Zuckerberg apologised for his company's errors in failing to better protect the personal information of its millions of users, a controversy that has brought a flood of bad publicity and sent the company's stock value plunging. However, as he answered questions, Facebook shares surged and closed up 4.5 per cent for the day, the biggest gain in two years.

Mr Zuckerberg said it had been “clearly a mistake” to believe the data-mining company Cambridge Analytica had deleted user data that it had - although Analytica said on Tuesday that it had deleted all the data. Mr Zuckerberg said Facebook had considered the data collection “a closed case” because it thought the information had been discarded and therefor that is why it did not inform users when it became aware of the data use in 2015.

The Facebook founder said the company is going through “a broader philosophical shift in how we approach our responsibility.” He said the company needs to take a “more proactive role” that includes ensuring the tools it creates are used in “good and healthy” ways.

He denied that Facebook, which has more than two billion monthly users across the world, was a monopoly. “It certainly doesn't feel that way to me,” Mr Zuckerberg said.

The billionaire appeared mostly comfortable with the questioning, with some senators struggling with some aspects of the technology. Although Mr Zuckerberg was at points to point out repeatedly that Facebook "does not sell" advertising and that users "have full control" over the data they provide.

Asked about the prospect of regulation, Republican Senator Lindsey Graham of South Carolina, Mr Zuckerberg said that his company would back "the right regulation".

Mr Graham asked whether the company "would work" with Congress to craft that regulation, to which Mr Zuckerberg replied: “Absolutely.”

Agencies contributed to this report

Key Points

• Zuckerberg says that some Facebook employees have been interviewed by Robert Mueller's team
• Technology billionaire calls it a 'mistake' not to ban Cambridge Analytics from Facebook in 2015
• Facebook is facing an 'ongoing arms race' with Russian interference, according to Zuckerberg
• CEO says he is willing to work with Congress to help create regulation for his industry

[11 April 2018 00:05 · Steve Anderson]

Senator Cory Gardner has read parts of the terms of service related to account deletion, which mentions that backup copies may persist after an account is deleted for some amount of time.

Mr Zuckerberg replays that he he doesn’t really know how long those backup copies are kept but is clear they are deleted.

[11 April 2018 00:12 · Steve Anderson]

Senator John Tester is asking about whether Facebook can do an audit of data if it is held in another country? Mr Zuckerberg says they are waiting on an investigation into Cambridge Analytica in the UK to complete their work.

[11 April 2018 00:17 · Steve Anderson]

Senator Tester says that Mr Zuckerberg has made clear several times that users own their data on Facebook, but with the money on advertising Facebook is making - and users aren't - it may be more accurate to say that Facebook owns the data.

[11 April 2018 00:18 · Steve Anderson]

The Associated Press have something on what they claim to be Mr Zuckerberg's notes:

If his notes are any indication, Facebook CEO Mark Zuckerberg expected senators to ask whether he'd resign. His notes acknowledge he's made mistakes and say the company is facing a "big challenge" but will solve this one too. 

Zuckerberg's notes were briefly visible to an Associated Press photographer during a hearing Tuesday in which he answered questions about privacy, election interference and other issues. 

The bullet-pointed pages include sections on "diversity," "competition," and GDPR, the European data-privacy rules that go into effect next month. Zuckerberg's notes warn him, "don't say we already do what GDPR requires." 

The notes even refer to Tim Cook, the Apple CEO who recently criticized Facebook. One note says there are "lots of stories about apps misusing Apple data, never seen Apple notify people." 

[11 April 2018 00:25 · Steve Anderson]

As we near the end, a favourite quote today. Senator John Kennedy had a blunt message for Mr Zuckerberg: "Your user agreement sucks."

It is clear that a number of senators felt the same today when it came to users knowing their rights.

A number of legislators complained about the length of the document, and asked whether users read it.

[11 April 2018 00:27 · Steve Anderson]

As we reach the end, Senator John Thune, the chair of the commerce committee, makes a final statement, where he implores Mr Zuckerberg for Facebook to allow speech from all ends of the political spectrum.

Senator Chuck Grassley, who opened proceedings, now brings to a close with the same message about political bias.

[11 April 2018 00:32 · Steve Anderson]

After around five hours of questions, Mr Zuckerberg finally gets to leave. He will be back tomorrow for another turn in front of the House Energy and Commerce committee. That begins at 10am ET (2pm GMT).

[11 April 2018 00:43 · Steve Anderson]

We were promised a grilling, but my colleague Andrew Buncombe was not impressed with the level of questioning from some senators.

[11 April 2018 00:48 · Steve Anderson]

And here is a longer report on what was quite a session.

[11 April 2018 00:49 · Steve Anderson]

We are ending our coverage for now. There is sure to plenty of reaction, and possibly some re-writing of questions in the House, to that session before Mr Zuckerberg does it all again in the morning.

Thanks for reading.