Senate tells Mark Zuckerberg: Don't let Facebook become a "privacy nightmare"

The Facebook CEO faces two days of grilling from federal lawmakers this week over privacy, the abuse of data and election interference on the platform.

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Federal lawmakers warned Facebook CEO Mark Zuckerberg against letting his near-ubiquitous social network from becoming a "privacy nightmare" for its billions of users.

"The story you've created represents the American dream," Sen. John Thune (R-S.D.), chairman of the Senate Commerce, Science and Transportation Committee, said to Zuckerberg on Capitol Hill on Tuesday. "You have an obligation to ensure that dream doesn't become a privacy nightmare."

Live Stream: Watch Mark Zuckerberg's Senate committee testimony

Tuesday marks the first of two days of public hearings during which federal lawmakers plan to question the CEO on a range of problems with the Facebook platform, including Facebook's privacy policies, the abuse of user data, use of the platform to interfere with democratic elections and the propagation of hate speech.

Over the past decade -- as Facebook amassed more than 2 billion users around the globe, grew its footprint by squashing or subsuming competitors, and came to dominate the ad industry -- these issues were slowly simmering in the background. They've come to the forefront of international discussion after a series of revelations about the handling of data from Facebook, all sparked by the new that a British consulting firm called Cambridge Analytica mishandled data from millions of Facebook users.

To address these matters, Zuckerberg is testifying in a joint hearing of the Senate Judiciary and Commerce Committees. On Wednesday, Zuckerberg will face the House Energy and Commerce Committee.

For both hearings, Zuckerberg has provided an opening statement in which he takes full, personal responsibility for his company's shortcomings.

Tuesday's joint hearing included 44 members of the Senate -- nearly half of the legislative chamber, signifiying how seriously the Congress is taking the issues.

Thune called the hearing "extraordinary," noting that Facebook's more than 2 billion users represent more than 1500 times the population of his state.

"Facebook's incredible reach is why we're here today," he said. "We're here today because of what you've described as a breach of trust."

Over the past few weeks, as the bad headlines continued to accumulate, Facebook has announced several steps the company is taking to counter election interference on the platform and to improve user security and privacy. For instance, the company last week noted that it was disabling a feature that let users look up other people by their phone number or email address. The feature, Facebook said at the time, was being abused by malicious actors who used it to scrape public profile information.

Facebook's steps so far are "unlikely to be enough," Thune said, noting that the Cambridge Analytica controversy is unlikely to be an isolated event.

"One reason so many people are worried about this incident is what it says about how Facebook works," he said. That users "may have technically consented to making their data available doesn't make people feel any better."

Some highlights from the hearing:

Is Facebook a Monopoly? Sen. Lindsey Graham (R-S.C.) posed this question to Zuckerberg, to which he retorted,

"It certainly doesn't feel like that to me!"

That question came after Graham grilled Zuckerberg over who, exactly, Facebook's competition is. Zuckerberg started to answer in a methodical way, first listing major technology companies like Google and Apple.

Graham cut him off to phrase the question in another way: "If I buy a Ford and it doesn't work, well, I can buy a Chevy. If I'm upset with Facebook, what's the equivalent?" Zuckerberg told the senator, "The average American uses eight different apps."

Zuckerberg is evasive about data mining for political purposes: Sen. Maria Cantwell (D-WA) asked Zuckerberg, "Do you know who Palantir is?" referencing the data mining company founded by Peter Thiel, a Facebook board member.

During this line of questioning, Zuckerberg said, "I'm not really familiar with what Palantir does."

Cantwell asked about Palantir's relationships to Facebook and to Cambridge Analytica. Zuckerberg said he was not aware whether Palantir has scraped data from Facebook, and he conceded he was not certain whether any Facebook employees worked alongside Cambridge Analytica as they assisted various political campaigns.

The senator also asked whether Zuckerberg had heard of "Total Information Awareness," a Bush-era Pentagon program aimed at using surveillance and data mining for national security purposes. Cantwell mused about Zuckerberg, "Is this guy outfoxing the foxes, or is he going along with a major trend in the information age to harvest information for political forces?"

Zuckerberg on using AI to identify hate speech: Responding to how the company tries to root out hate speech, Zuckerberg told lawmakers, "Determining if something is hate speech is very linguistically nuanced."

The company has struggled to do so, even though it's already successfully applied AI to flag potential terrorist propaganda on the platform, Zuckerberg said. He said he's optimistic that "acorss a five to 10 year period" Facebook will be able to apply AI to effectively flag potential hate speech.

Addressing hate speech in Myanmar: Facebook has been used in Myanmar to propagate hate speech and incite violence against Rohingya Muslims, a group facing an ethnic cleansing campaign. Zuckerberg told lawmakers that Facebook has hired dozens of more Burmese language content reviewers. The company is also working with civil society in Myanmar to identify "hate figures," Zuckerberg said, to remove specific people rather than specific pieces of content from the platform.