It was a stark change from the morning hearing, when Senate Intelligence Committee members were more collegial and appeared to share similar concerns with Facebook and Twitter over disinformation and foreign influence on their site.
The top Democrat in the House hearing, Representative Frank Pallone of New Jersey, accused his Republican counterparts on the committee of having political motives behind their accusations.
“President Trump and many Republicans have peddled conspiracy theories about Twitter and other social media platforms to whip up their base and fund-raise,” Mr. Pallone said. “I fear the Republicans are using this hearing for those purposes instead of addressing the serious issues raised by social media platforms that affect Americans’ everyday lives.”
Representative Joe Barton, a Republican of Texas, said: “We wouldn’t be having this discussion if there wasn’t a general agreement that your company had discriminated against conservatives.”
Mr. Dorsey, who read opening remarks from a phone while live-tweeting, said the company has found no evidence of political bias.
“Looking at the data, we analyzed tweets sent by all members of the House and Senate, and found no statistically significant difference between the number of times a tweet by a Democrat is viewed versus a Republican, even after our ranking and filtering of tweets has been applied,” Mr. Dorsey said.
Representative Mike Doyle, a Democrat of Pennsylvania, accused Representative Kevin McCarthy, the majority leader, of sounding the alarm of anti-conservative bias for political gains.
He described those accusations as a “load of crap.”
— Cecilia Kang
Dorsey Avoids Taking Sides
As House lawmakers threw political jabs in the hearing, Mr. Dorsey managed to steer clear of taking sides.
Representative Kathy Castor, Democrat of Florida, asked Mr. Dorsey if he felt manipulated by Republican politicians who have raised accusations of anti-conservative bias for fund-raising purposes.
Mr. Dorsey demurred.
“I do believe there is growing concern around power companies like ours hold,” Mr. Dorsey said. “People do see us as a digital public square and that comes with certain expectations.”
Representative Ben Luján, Democrat of New Mexico, asked Mr. Dorsey to compare the number of bot accounts Twitter took down that followed President Trump versus President Obama. Mr. Luján knew the answer to his own question. (Two million follower accounts for Obama were taken down versus 320,000 for Mr. Trump, a sign, Mr. Luján suggested, that Twitter was not biased against Republicans.)
Mr. Dorsey, however, did not weigh in the issue.
“Not sure of those details,” Mr. Dorsey said. “But it was a broad-based action across Twitter.”
— Cecilia Kang
An Interruption, Followed by Auctioneering
Roughly 90 minutes into the afternoon hearing, right-wing activist Laura Loomer stood up from her seat in the back of the room and began yelling over committee members to “stop the bias.”
Holding up her cellphone camera so that she could film her own interruption, Ms. Loomer accused tech companies of holding a bias against conservative voices. As committee members asked her to take her seat so that they could resume their discussions, one lawmaker decided to take matters into his own hands.
Representative Billy Long, Republican of Missouri, imitated an auctioneer’s patter, running a live auction as Ms. Loomer repeated her accusations in an ever-louder voice. Mr. Long owned an auction business for decades.
Leaning close into his microphone and speaking in a steady, rapid-fire voice, Mr. Long called out, “Fifty cents, a dollar!” as Ms. Loomer was escorted from the room.
Mr. Long’s performance drew laughs from lawmakers of both parties.
— Sheera Frenkel
A Glossary of Terms Used in the Hearing
Lawmakers and Mr. Dorsey are using a lot of jargon in Wednesday afternoon’s House hearing. Here are explanations of some of those terms.
Shadow banning Shadow banning is a moderation tactic for online discussions that hides an individual’s comments from other users involved in the conversation without letting the person know that their comments are hidden. The practice is intended to limit the impact of trolls and abusers without instigating them to create fresh accounts to continue their behavior.
Conservative Twitter users have recently rallied around claims that Twitter shadow bans users based on their politics. In July, President Trump tweeted that he would look into the “discriminatory and illegal practice.” However, Twitter says it does not shadow ban users. Twitter’s algorithmic timeline ranks tweets based on a number of factors, causing some tweets to appear higher in the timeline than others.
Signal Twitter ranks tweets based on what the company calls signals. Signals include a user’s actions on Twitter, as well as actions that other accounts make when interacting with a user’s account. Signals are often specific to a particular user’s account — for instance, if you follow a certain celebrity or politician, their tweets might appear higher in a search than tweets from other users. Twitter also considers signals of authenticity, such as whether a user has verified his phone number or email address, when ranking tweets. If a user is blocked or muted by a large number of accounts, their tweets might appear lower in search or in the Twitter timeline.
Bot A Twitter bot is an automated account that publishes tweets without human intervention. Some bots publish useful information like automated earthquake alerts, but bots are also used in some harassment and misinformation campaigns to amplify certain messages over the voices of human users.
Downranking This is the practice of displaying particular tweets or users lower in timeline and search. When Twitter introduced its service, it displayed all tweets in chronological order. As the service grew, Twitter switched to a timeline ordered by an algorithm. In the new timeline, Twitter attempts to rank tweets based on quality and relevance. Tweets that Twitter’s algorithm flags as low-quality are downranked. Twitter also sometimes hides tweets behind a warning that tells the user that the content could be abusive or offensive.
— Kate Conger
Executives Pressed on Opioid Ads
Senator Joe Manchin III, Democrat of West Virginia, asked the executives about their responsibilities to control harmful behavior on their platforms.
He noted that the illegal sale of opioids on their platforms still exists. Mr. Manchin asked if the companies felt that they should bear some responsibility for deaths related to opioid sales on their platform.
Neither Mr. Dorsey nor Ms. Sandberg answered that question directly, and they stressed the importance of laws that protect internet platforms from lawsuits.
The executives said they could be open to further reforms to a law that provides a safe harbor from liability to internet companies, Section 230 of the Communications Decency Act. The law, passed in 1996, is considered the Holy Grail of internet policy, providing broad protections that are credited with the rapid growth of Silicon Valley.
But they said that the protection also allows them greater freedom to police bad behavior without fear of legal actions.
“We benefit from a lot of protections it gives,” Mr. Dorsey said.
“The safe harbor of 230 has been very important in enabling companies like ours to do proactive enforcement without increasingly our liability,” Ms. Sandberg said. “So we would like to work very closely on how this is enacted.”
— Cecilia Kang
How Do You Tell Users Something Is Fake?
Lawmakers pressed the two executives on how their platforms notify users of foreign influence campaigns.
Ms. Sandberg said Facebook is getting better at letting users know of fake accounts and ads. She raised the example of an event in Washington, D.C., that was promoted by an inauthentic account. When Facebook detected the account, the company took down the event and notified users who indicated their interest in attending.
[Take our test to see if you can spot the deceptive Facebook post.]
Senator Susan Collins, Republican of Maine, criticized Twitter for Russian activity that affected her account but that was only brought to her attention by researchers from Clemson University.
Mr. Dorsey admitted that Twitter needed to improve its process of detecting fake accounts and notifying users, and said the company wants to work more with academics.
“We do believe in transparency and a big part of where we need the most work,” Mr. Dorsey said.
— Cecilia Kang
Senators Hint at Regulation
Regulation is coming. Senators made that clear in their statements to Ms. Sandberg and Mr. Dorsey. But the precise form of that legislation is unclear.
“Congress is going to have to take action here,” said Senator Mark Warner, Democrat of Virginia. “The era of the Wild West in social media is coming to an end.”
Several lawmakers indicated that they saw an opening for regulation related to election interference on social media platforms, because they considered it a threat to national security. Other senators appeared to favor a privacy approach, focusing on individual rights to control personal data.
Data privacy, said Senator Ron Wyden, Democrat from Oregon, would serve as the “foundation” of legislation that he has previously discussed with Twitter and Facebook.
Social media companies are resigned to the notion that regulation is on its way. Twitter and Facebook have endorsed the Honest Ads Act, a proposal that would require more transparency about who is paying for online ads, and have begun building so-called ad transparency centers on their platforms.
But expect some resistance from the tech giants. In a white paper, Mr. Warner proposed 20 legislative possibilities. When pressed on one of the proposals, Ms. Sandberg replied, “We don’t think it’s a question of whether regulation, we think it’s a question of the right regulation.”
— Kate Conger
Contrasting Styles from Tech Executives
Ms. Sandberg and Mr. Dorsey’s opening statements before the Senate hearing displayed their obvious differences.
Ms. Sandberg, who was born in Washington, and spent years living there during her time at the Treasury Department, appeared confident in her opening remarks. Speaking clearly and with practiced pacing, she complimented the committee’s previous work on election interference.
Mr. Dorsey stumbled during his opening, forgetting to turn on his microphone and reading from a cellphone he held in his hand. He added that he was also live-tweeting his opening remarks through his Twitter account.
While Ms. Sandberg made consistent eye contact with the senators, Mr. Dorsey appeared to be reading from his phone between questions.
— Cecilia Kang and Sheera Frenkel