The senators groused and grimaced and expressed general disapproval with all that has gone wrong at Facebook, but they stopped short of giving its chief executive, Mark Zuckerberg, reason for panic on Capitol Hill on Tuesday.
Zuckerberg's five-hour grilling by 44 lawmakers confirmed Facebook is in for a prolonged period of government scrutiny, but also highlighted how unprepared Congress is to impose game-changing rules on the world's biggest social network.
Once lawmakers finally got Zuckerberg where they wanted him — under oath and forced to answer all their questions about Facebook's role in the 2016 election and its lax privacy protections — they struggled to articulate how exactly they want his company to change.
The proceedings brought into stark relief how San Francisco Bay Area innovation can be more nimble than Washington bureaucracy. Zuckerberg had to spend a good deal of time explaining the basic workings of Facebook, such as how its Messenger app functions. The biggest revelation to come out of the hearing may have been that Facebook has been approached by special counsel Robert S. Mueller III and is cooperating with his investigation into Russian meddling in the 2016 presidential election.
As the highly anticipated hearing that was supposed to be a reckoning for Facebook stretched toward evening, the company's stock price lifted; investors watching it did not see signs that lawmakers were equipped and ready to rein in the company.
Instead, the lawmakers mostly aired grievances. They had many.
Among the notable exchanges was one in which Sen. Richard J. Durbin (D-Ill.) demanded of Zuckerberg: "Would you be comfortable sharing with us the name of the hotel you stayed in last night?" No, Zuckerberg would not. Durbin emphasized that the loss of control of such personal details by Facebook users necessitated the hearing.
They drilled down on privacy invasions and other issues dogging Facebook, such as foreign operatives using the platform to influence elections, a proliferation of hate speech and calls for ethnic violence in Myanmar, and its vulnerability to discriminatory marketing practices. Again and again, Zuckerberg was asked how the data of 87 million unsuspecting Facebook users landed in the hands of Cambridge Analytica, a political consulting firm that worked on the Trump campaign.
"We didn't take a broad enough view of our responsibility, and that was a big mistake. It was my mistake, and I'm sorry," Zuckerberg said in his opening statement.
California Sen. Dianne Feinstein demanded to know why Cambridge Analytica wasn't banned when Facebook learned it had abused the platform years ago. California Sen. Kamala Harris demanded to know why Facebook waited until the media learned of the abuse — only months ago — to inform its users about it.
"In retrospect, we clearly view it as a mistake that we didn't inform people," Zuckerberg said. "Knowing what we know now, we should have handled a lot of things differently."
If the tech icon who favors hoodies and gray T-shirts felt out of place in his Washington attire of a dark suit and bright blue tie, it didn't show. Zuckerberg — who is also scheduled to appear before the House Energy and Commerce Committee on Wednesday — confidently answered questions and rarely stumbled.
Pressed on whether Facebook should be regulated more, Zuckerberg said he would support the "right regulations" that "capture the nuances of how these services work."
Working in Facebook's favor is the reluctance of Republicans to impose rules more strict than those the company already seems to be embracing. But even they warned they are tired of the company's long history of abusing the trust of users, publicly apologizing and then repeating the cycle again.
"I don't want to vote to have to regulate Facebook, but by God I will," said Sen. John Kennedy (R-La.). "I just don't feel like we are connecting. There are going to be a whole bunch of bills introduced to regulate Facebook. It is up to you whether they pass or not."
The Menlo Park, Calif., company has been on the defense since it downplayed the effect of Russian interference on its platform during the 2016 presidential election. The widening Cambridge Analytica scandal has also resulted in a new Federal Trade Commission investigation into whether Facebook violated a 2011 consent decree requiring the company to properly inform users about changes to their privacy settings.
The biggest threat to Facebook, however, would be new regulations that challenge the company's lifeblood: access to increasing amounts of personal data from its 2 billion users.
Such access is necessary, Zuckerberg argued, to support Facebook's ad-driven business model.
"We want to offer a free service anyone can afford," Zuckerberg told the lawmakers. "It's the only way we can reach billions of people."
Rather than wait for regulation, Facebook in recent days has announced a slew of changes aimed at boosting transparency for users and limiting how much data is accessible to outside apps. Zuckerberg has also expressed support for the Honest Ads Act, a bipartisan proposal to apply the same disclosure rules to political ads online as those on television or print media.
Sen. Lindsey Graham (R-S.C.), however, challenged Zuckerberg on the issue of competition, asking the executive if he thought Facebook was a monopoly.
"It certainly doesn't feel that way to me," Zuckerberg said, eliciting chuckles in the room.
Asked if new privacy rules introduced by European regulators were appropriate, Zuckerberg was less than specific in his response. "I think they get things right," he said, drawing even more laughter.
After the hearing, Graham said the "dark side" of Facebook needs to be addressed, and the government may not have the tools to address it. "It could possibly take the creation of new laws and regulations to deal with this platform," he said in a statement.
Some Democrats are ready to impose them immediately. Sen. Richard Blumenthal (D-Conn.) said Facebook's business model would always favor data collection over user privacy and security, and new laws are needed to keep it in check.
"We've seen the apology tours before," Blumenthal said. "I don't see how you can change your business model unless there are specific rules of the road."
He and Sen. Ed Markey (D-Mass.) pressured Zuckerberg to support their Consent Act, which would require tech companies to get explicit permission from users before using or sharing their personal data.
Zuckerberg said he supports the principle of consent but declined to endorse any such bill, saying "the details [of a bill] matter a lot." Markey retorted that the act is a carbon copy of the new European regulation Facebook is going to have to live with starting next month.
But the measure has limited traction in a Congress conflicted about how to oversee a tech powerhouse that has had a profound effect on democracy but operates in a way many still struggle to understand. The platform is so widely used by voters that any unintended consequences of regulations could have considerable political fallout.
One of the few senators able to rattle Zuckerberg was Sen. Ted Cruz (R-Texas), who complained the platform was censoring conservative content.
"There are a great many of Americans deeply concerned Facebook and other tech companies are engaged in a pervasive pattern of bias and political censorship," Cruz said. Among his complaints: The muting of a Chick-fil-A appreciation page and the page of Trump supporters Diamond and Silk.
Zuckerberg said Facebook was a platform for all ideas and dismissed a suggestion from Cruz that conservatives were not getting hired at the company. He said Facebook did not fire Oculus VR founder Palmer Luckey because of his political ideology, but would not elaborate on the reason for the termination.
Concerns that the company is also failing to police at the fringes were also fired at Zuckerberg.
Senators pressed him about the spread of misinformation and hate speech in Myanmar that has fueled additional violence against the Southeast Asian nation's Rohingya minority group. Sen. Christopher Coons (D-Del.) asked why the onus always seems to be on users to flag problematic content rather than the company itself.
He relayed an anecdote involving an erroneous photograph he discovered of himself that was being shared on Facebook..
"Isn't it Facebook's job to better protect users?" he asked.
Zuckerberg acknowledged the problems exist — but suggested the company is already ahead of Congress in addressing it. He noted there are 20,000 employees engaged in monitoring and security at Facebook, and the company is "hiring dozens of more Burmese language content reviewers."
Along with that human oversight, Zuckerberg proposed a technological solution to a technological problem.
He said artificial intelligence and sophisticated algorithms will be part of the company's broader plan to weed out bad actors on its platform. Lawmakers posed few questions on that.
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6:30 p.m.: This article was entirely rewritten to include broader political context.
4:40 p.m.: This article was updated with comment from Sen. Maggie Hassan.
3:50 p.m.: This article was updated with comments from Sens. Kamala Harris and John Kennedy.
3:10 p.m.: This article was updated with comment from Sen. Dean Heller.
2:25 p.m.: This article was updated with details about testimony regarding Myanmar.
2:15 p.m.: This article was updated with comment from Sen. Christopher Coons.
1:50 p.m.: This article was updated with comment from Sen. Richard Blumenthal.
1:30 p.m.: This article was updated after questions from Sen. Ted Cruz.
1:15 p.m.: This article was updated after questions from Sen. Amy Klobuchar.
12:55 p.m.: This article was updated after questions began to focus on regulation.
12:10 p.m.: This article was updated after the hearing began.