A bus stop advertisement by Facebook in Berlin | Sean Gallup/Getty Images Facebook considering limits on targeted campaign ads The possible reining in of political ‘microtargeting’ is part of a broader reassessment of campaign messaging policies.

MENLO PARK, California — Facebook is considering restricting politicians' ability to use highly detailed demographic and personal information to narrowly target would-be voters with ads, policy chief Nick Clegg confirmed Thursday in an interview with POLITICO — in a sign of potential softening of the social network's broadly permissive policy on political advertising.

The possible reining in of political "microtargeting," part of a broader reassessment of Facebook's policies around campaign messaging, comes just weeks after CEO Mark Zuckerberg made two trips to Washington to defend the company against attacks from Democrats who say its hands-off approach distorts democracy. Google is also considering changes to its political ad policy, The Wall Street Journal reported Wednesday, while Twitter last week angered Republicans by announcing it's ending political advertising on its platform altogether.

The result is that all three big online companies remain embroiled in criticism over their approaches to political advertising, a potentially multibillion-dollar market in the 2020 campaign cycle. Facebook dominates that market, raking in $857 million on political and issues-based advertisements between May 2018 and late last month, the company has disclosed. Democrats have been especially harsh on the company's refusal to fact-check political candidates' ads, which Zuckerberg has called a matter of free expression.

The company is standing by that approach. But it's actively discussing making other tweaks to its political ads policy, said Clegg, Facebook's head of policy and communications.

“We’re working on a whole series of possible amendments and changes to our approach on political ads, so it’s not the end of the story," the former British deputy prime minister said at Facebook headquarters.

Republicans have decried limits on political advertising as antithetical to free-speech principles.

Asked if adjustments to the company’s approach to microtargeting is indeed one of the possible changes under consideration, Clegg said yes. NBC News, citing unnamed company sources, first reported earlier this week that Facebook was considering limiting the practice.

Clegg declined to discuss other potential changes, saying the company is still in the decision-making process. But he said Facebook is also looking at "whether users are sufficiently aware of when they’re being exposed political ads as opposed to organic content," the company's term for material such as ordinary users' posts.

Microtargeting lets campaigns tap Facebook's vast caches of data to reach specific audiences with pinpoint accuracy, going after voters in certain neighborhoods, jobs and age ranges, or even serving up ads only to fans of certain television shows or sports teams. It's drawn criticism from people such as Federal Election Commission Chairwoman Ellen Weintraub, who wrote in a recent Washington Post op-ed that the practice makes it "easy to single out susceptible groups and direct political misinformation to them with little accountability, because the public at large never sees the ad."

Any move to restrict the practice would be sure to invite criticism from Republicans, who have decried limits on political advertising as antithetical to free-speech principles. And Democrats will probably say curbing microtargeting does nothing to address their broader concerns about Facebook's political ad policy.

Presidential candidates Joe Biden and Sen. Elizabeth Warren (D-Mass.) are among those who have been hammering Facebook over its policy of declining to fact-check political advertisements, which can result in outright false or otherwise misleading ads running on the site. Zuckerberg staked out an aggressive defense of the company's permissive policy in a speech at Georgetown last month, maintaining that it would be troubling, even un-American, for a private company to make judgment calls on what political campaigns can say to voters.

But potential microtargeting limits and other possible tweaks in the offing signify that the company is open to at least scaling back the wide berth it gives paid political messaging.

“We’re now working actively to reflect, in the face of all the criticisms, on what we should do to adjust our own posture on all this. We want to get this right,” Clegg said. "It's actually quite a good thing in the long run that we're having this debate now rather than two months before the election."

The public face of that debate has up to now pitted Facebook firmly against Twitter and its move to drop all political and issue ads. Twitter's action has drawn its own rebukes, both from Republicans who say they're troubled by the free-speech implications and from liberals like Warren, who recently tweeted that it would let fossil fuel companies "buy ads defending themselves and spreading misleading info" but forbid climate ads "holding those companies accountable. "

Clegg reiterated that, even amid the policy tweaks Facebook is mulling, it won't be following Twitter's lead.

"We don’t think getting out of political ads altogether is the answer," he said, arguing that Twitter's approach has a "ton of downsides," such as the difficulty of determining what counts as a political or issue ad and the disadvantage some argue such a ban places on non-incumbent politicians.

But even more incremental changes like a restriction on microtargeting would also invite further debate.

Alex Stamos, Facebook’s former chief security officer, told POLITICO that curbing microtargeting would help prevent advertisers from bombarding heavily tailored audiences with ads and reduce the incentive for campaigns and advocacy groups to amass personal data on narrow subsets of voters. He said such a step would bring social media advertising more in line with the level of targeting possible in direct mail and television.

On the other hand, Jesse Blumenthal, who leads the tech policy portfolio for the Koch umbrella network Stand Together, contended that microtargeting through Facebook and Google is just a natural evolution of that traditional messaging. Political advertisers have long aimed their messages at specific audiences, buying television ads during certain programs or sending mailers to particular ZIP codes, he said.

“These are private companies and they get to make their own decisions, but, from our perspective, free speech is good and more speech is better,” he said. “These sort of calls to limit or curtail or otherwise diminish political speech are really troubling.”

For his part, Clegg pointed to Twitter's new policy, which Dorsey rolled out in a series of tweets seemingly aimed right at Facebook, as an example of the difficulty of crafting the right policy on political advertisements.

“First day everyone praises it, and now everyone’s saying maybe that’s not quite such a good idea," Clegg said. "We’re all grappling to try to get the right balance."

Steven Overly contributed to this report.

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