Five months after Facebook founder Mark Zuckerberg appeared before Congress, the US government once again invited tech executives to a series of high profile hearings.
Facebook COO Sheryl Sandberg and Twitter CEO Jack Dorsey first faced the Senate Select Intelligence Committee, before Mr Dorsey was questioned on his own by the House Energy and Commerce Committee.
Notably absent from the proceedings was Google, after the firm failed to send a senior executive to Washington. In place of a Google representative, the Senate committee left an empty chair.
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Live Updates
12:00
With two-and-a-half hours to go until Sheryl Sandberg follows in the footsteps of her boss, here's a reminder of how Mark Zuckerberg's hearing went in April.
As it happened: Mark Zuckerberg tells Congress his own data was taken through Facebook
After navigating nearly five hours of questions from 44 US senators on Tuesday about the abuse of citizen's data, Facebook founder Mark Zuckerberg has done it all again on Wednesday. Once again, he was attacked on a range of fronts: as well as the company's failure to protect its users data, politicians questioned the site's perceived bias against conservative voices, and its use for selling illegal materials like drugs.
12:10
Both Twitter CEO Jack Dorsey and Facebook COO Sheryl Sandberg have already prepared statements to read at the opening of their hearings.
In her 10-page testimony, Sandberg admits Facebook's past mistakes but says the company is making efforts to address the issue of election interference on its platform.
"We were too slow to spot this and to slow to act," Sandberg will say. "That's on us. This interference was completely unacceptable. It violated the values of our company and of the country we love."
13:49
For his part, Jack Dorsey will argue in his opening statement that "Twitter does not use political ideology to make any decisions."
Twitter has long tried to position itself as a platform that encourages free speech, however it has struggled to strike the right balance when it comes to hate speech.
According to a recent report in The Wall Street Journal, Dorsey personally intervened in order to reinstate the account of far-right firebrand Alex Jones.
14:05
Here's the opening to Twitter boss Jack Dorsey's prepared statement:
Thank you for the opportunity to appear before the Committee today so I may speak to you and the American people.Twitter’s purpose is to serve the public conversation. We are an American company that serves our global audience by focusing on the people who use our service, and we put them first in every step we take. Twitter is used as a global town square, where people from around the world come together in an open and free exchange of ideas. We must be a trusted and healthy place that supports free and open discussion.Twitter has publicly committed to improving the collective health, openness, and civility of public conversation on our platform. Twitter’s health is measured by how we help encourage more healthy debate, conversations, and critical thinking. Conversely, abuse, malicious automation, and manipulation detracts from the health of our platform. We are committed to hold ourselves publicly accountable towards progress of our health initiative.Today, I hope my testimony before the Committee will demonstrate the challenges that we are tackling as a global platform. Twitter is approaching these challenges with a simple question: How do we earn more trust from the people using our service? We know the way earn more trust around how we make decisions on our platform is to be as transparent as possible. We want to communicate how our platform works in a clear and straightforward way.
14:25
Notably absent from today's proceedings is a representative of Google.
Beside the Twitter and Facebook execs will be an empty chair, symbolizing the fact that the tech giant didn't deem it necessary to send a senior figure.
Instead, Google offered to send its top lawyer, Kent Walker, but the Senate Intelligence Committee declined.
Walker compiled written testimony for the occasion, and even if he doesn't get a chance to deliver it verbally himself, you can read in a blog post he published it yesterday.
14:38
The hearing is underway, and we start with some words by Chairman Richard Burr about the recently passed John McCain.
McCain's place at the hearing is marked with a single white rose on a black cloth.
"He will be dearly missed," Chairman Burr says.
14:43
Chairman Burr's says in his opening remarks that "business as usual" for these tech firms is not good enough.
"We've identified the problem, now we've got to find a solution," he says.
14:46
He also adds a jibe at Google for failing to send the "right senior executive".
His sentiments are echoed by Vice Chairman Mark Warner, who takes over from Burr. He says he is "deeply disappointed" in Google for not taking the issues being discussed today seriously enough.
14:49
Apparently Alex Jones is in the building...
14:58
The far right conspiracy theorist has been the subject of a lot of debate surrounding free speech on the social media platforms, which saw him removed and then reinstated to Twitter earlier this month.
You can read the full story here:
Twitter has finally banned Alex Jones. Except it hasn't at all
CEO Jack Dorsey previously said that Jones had not broken any of his site's rules
15:01
Meanwhile, inside the hearing, Facebook COO describes the situation as an "arms race" between her company and nefarious actors.
15:04
Twitter CEO Jack Dorsey is up now to deliver his opening statement. And, of course, he's live tweeting it.
15:06
Here's Dorsey live tweeting his opening remarks. Some coordination there to speak and tweet at the same time.
15:20
The pattern of questions echo those faced by Facebook CEO Mark Zuckerberg in April. Many of them are technical questions about the platforms, demonstrating some of the Senators' lack of fundamental understanding of how these companies work.
Vice Chairman Warner blames Facebook for a lack of transparency when it comes to what its doing with people's data and why. "Most users are in the dark," he says.
15:29
Alex Jones update: He has entered the hearing, and is apparently spectating from the front row.
15:48
Both Dorsey and Sandberg seem unperturbed by the presence of the InfoWars host.
Sandberg responds to a question by Senator Martin Heinrich by saying Facebook is getting smarter at detecting and preventing threats to elections.
Dorsey echoes her words, detailing AI tools to recognize patterns of behavior that allow people to artificially amplify information.
15:53
On the topic of so-called Fake News, Sandberg says: "Finding the line between what is hate speech and what is misinformation is very, very difficult."
15:56
The hearing is in recess now, and a live video of Alex Jones is being shared, appropriately, on social media.
He is prowling the corridors behind the hearing and looks and sounds very purposeful – though it's still not clear what his purpose actually is.
"I'm here to face my accusers," he barks to no one.
15:58
The conspiracy theorist just managed to corner a Senator, though the poor quality of the video stream makes it difficult to determine which one.
Jones' words are clear though: "Stop violating the first amendment... Shame on you, you un-American tyrant."
The hearings went slightly better than Mr Zuckerberg's venture to the Capitol in April, when members of Congress needed explanations of some of the platform's basic functions. This time, they challenged the executives with hard-hitting questions about foreign actors and political bias.
The questioning was interrupted several times by conservative media figures like Alex Jones and Laura Loomer. Both were escorted out of the hearing, but continued broadcasting their views loudly to reporters waiting in the hallways.
