James Martin/CNET

Will Facebook be regulated?

CEO Mark Zuckerberg opened the door on Tuesday, telling Congress he'd welcome regulation, if it's the right regulation.

The 33-year-old multibillionaire is testifying before a joint hearing of the Senate Judiciary Committee and Senate Commerce Committee on Tuesday. On Wednesday, he'll make a similar appearance before the House Energy and Commerce Committee.

Zuckerberg's presence on Capitol Hill marks one of the most high-profile mea culpas in tech history. It comes as Facebook addresses questions about the biggest scandal to hit the social network since it was founded 14 years ago. Zuckerberg wants to reassure lawmakers, investors, advertisers -- not to mention Facebook's 2.2 billion users -- that the social network can be trusted with their data.

"My top priority has always been our social mission of connecting people, building community and bringing the world closer together," Zuckerberg said in prepared remarks released Monday and echoed repeatedly to senators. "Advertisers and developers will never take priority over that as long as I'm running Facebook."

Rarely do congressional hearings take on the importance that Zuckerberg's testimony has. The company is embroiled in a data scandal that crosses international borders and reportedly influenced elections. South Dakota Sen. John Thune noted the heightened importance of the testimony as the hearing started.

"The world is listening," he told Zuckerberg.

Zuckerberg acknowledged his company had made mistakes, telling senators the social network is "going through a broader philosophical shift." Facebook's policies have largely been reactive, requiring users to complain about content or posts on the social network, he said on several occasions. That, Zuckerberg, said needs to change.

Many of the senators honed in on the data scandal, in which consultancy Cambridge Analytica reportedly obtained 87 million user profiles, and Russian meddling in the 2016 presidential election. That led to a question from Vermont Sen. Patrick Leahy, who asked Zuckerberg if Facebook had been subpoenaed by Special Counsel Robert Mueller's investigation into Russian meddling in the election.

Zuckerberg said Facebook is working with the special counsel though hadn't himself been interviewed.

Senators also questioned Zuckerberg about how user data is used, particularly for advertising.

"Advertisers tell us who they want to reach and we do the placement," Zuckerberg said. "We do not sell data to advertisers."

Unsurprisingly, senators queried Zuckerberg on regulation, particularly on whether he'd support an opt-in standard for users before they give up their data similar to the European General Data Protection Regulation privacy rule that comes into effect next month. Zuckerberg agreed "in principle" but didn't commit, adding "details matter."

The proceedings slowed at some points, when tech jargon or legal lingo need to clarified. But Louisiana Sen. John Kennedy cut through the dense language giving Zuckerberg a blunt assessment of Facebook's terms of service."Your user agreement sucks," Kennedy said to chuckles, adding it exists to cover Facebook's "rear end." He suggested Facebook rewrite it for average users.

The testimony comes in the wake of the widening Cambridge Analytica scandal, which forced Facebook to acknowledge in March that data on millions of users was shared without their permission. That admission came only after a whistleblower gave the details to The New York Times and The Guardian's Observer, which revealed that University of Cambridge lecturer Aleksandr Kogan had created a personality quiz several years ago that could also collect profile, location and friends data for hundreds of thousands of people.

Kogan was also able to collect information about friends of his app's users, giving data on many as 87 million people's profiles, Facebook said. Kogan then reportedly passed that info to UK-based Cambridge Analytica.

Eventually, Facebook found out about the episode. In 2015, Facebook asked Kogan and Cambridge Analytica to sign documents promising the data had been destroyed. It didn't publicly disclose any of this until a day before the New York Times and Guardian stories were published.

The news that Facebook lost control of its users' data -- and failed to disclose it -- has raised a fundamental question of trust in the world's largest social network. Facebook is a free service that makes its money by capitalizing on the details that its users share. In 2017, the company racked up more than $40 billion in sales.

Now playing: Watch this: Zuckerberg says he's OK with more regulation

Some advertisers have already ditched Facebook, and some users started a #DeleteFacebook campaign on Twitter. Prominent tech executives -- including Tesla CEO Elon Musk and Apple CEO Tim Cook -- have chastized the company. Musk, who deleted Facebook pages for his Tesla and SpaceX companies, said the social network gave him "the willies."

"It's clear now that we didn't do enough to prevent these tools from being used for harm," Zuckerberg said in his prepared testimony. "That goes for fake news, foreign interference in elections and hate speech, as well as developers and data privacy."

Into the lion's den

Public relations and policy experts say Zuckerberg needs to make a convincing apology in Washington. He also needs to reassure lawmakers, who will be tempted to use the event to grandstand. And most of all, he needs to convince us that things will change.

Zuckerberg has begun promising to fix Facebook's "privacy, safety and democracy" issues. Facebook has reset its advertising and data policies. For example, it's stopped working with third-party data providers, such as Acxiom and Experian, to help marketers target ads at Facebook users. It's also booted other data analysis firms, including AggregateIQ and CubeYou, that have been accused of misusing data.

The social media giant is also limiting the data it will share with outside developers. Facebook is going to approve all apps that request access to information such as check-ins, likes, photos, posts, videos, events and groups.

Facebook will also further lock down its "Login" feature, a sign-in tool for apps that Kogan used to collect data. As of last week, software developers won't be able to ask for personal information, such as religious affiliation, political views, relationship status, education and work history.

In the interest of privacy, Facebook also said last week it's disabling a feature that allowed users to search for other users' profiles using phone numbers or email addresses. That left user profiles vulnerable to being "scraped," or collected, by bad actors. The company also put more limits on what information developers could gather from a handful of Facebook services, including its Events, Groups and Pages features. For example, apps will no longer get to see the guest list for an Event page, or the member list for a Group page.

If all that is supposed to restore users' confidence in Facebook, it doesn't seem to be working. In a poll by CBS News, respondents largely said that the company's response to the scandal has been unacceptable and that they also seriously doubt Facebook can protect them in future. (CBS News is a corporate sibling of CNET.)

Originally published April 10 at 5:00 a.m. PT.

Updated at 3:35 p.m. PT: Adds quote from Sen. John Kennedy.

Updated at 2:25 p.m. PT: Adds quote regarding opt-in legislation.

Updated at 1:22 p.m. PT: Adds quote regarding advertising.

Updated at 12:56 p.m. PT: Adds additional quotes from hearing.

Updated at 12:29 p.m. PT: Adds quote from Mark Zuckerberg.

Updated at 11:45 a.m. PT: Adds quotes from hearing.

Updated at 7:09 a.m. PT: Added information about a poll of Americans on Facebook's handing of user data.

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