Facebook chief executive Mark Zuckerberg drew fresh ire from Democratic presidential candidates, free speech experts and civil rights advocates, who argued his speech in Washington this week failed to acknowledge the problems the tech giant’s practices create.

The swift, broad nature of the criticism — including from the daughter of the Rev. Martin Luther King Jr. — largely centered on Zuckerberg’s acknowledgment of the dangers of disinformation and the potential for an “erosion of truth” online, even as he defended Facebook’s rules that allow politicians, including President Trump, to lie in their election ads.

Sen. Elizabeth Warren (D-Mass.) late Thursday charged that Zuckerberg’s speech “shows how little he has learned from 2016,” when Russian agents spread propaganda to influence the last presidential race, “and how unprepared Facebook is to handle the 2020 election.”

“Facebook is actively helping Trump spread lies and misinformation,” she added in a series of tweets. “Facebook already helped elect Donald Trump once. They might do it again — and profit off of it.”

This month, Facebook declined to take down an ad from Trump’s campaign that contained falsehoods about former vice president Joe Biden, prompting widespread criticism from the party. Biden’s 2020 presidential campaign, which had requested its removal, similarly expressed outrage with Zuckerberg after his Georgetown speech. Biden spokesman Bill Russo said in a statement that the Facebook leader cloaked company policy “in a feigned concern for free expression.”

Zuckerberg’s remarks Thursday were a rare, public attempt to explain his vision of free expression in the digital age. He called on the United States to set an example for tailored regulation, and stressed that Facebook must stand strong against governments that seek to “pull back” on free speech in the face of heightened social and political tensions.

In doing so, Zuckerberg defended the company’s policy around political ads. “I think we’re in the right place on this,” he told The Washington Post in an interview before his address. “In general, in a democracy, I think that people should be able to hear for themselves what politicians are saying."

Zuckerberg presented his beliefs — that societies tend to regret the instances in which they limit one’s right to express their views — through the lens of history, at one point citing King, his letter from Birmingham jail and his arrests for peaceful protest.

But the Facebook leader’s remarks soon raised eyebrows with a member of King’s family: his daughter, Bernice King. The civil rights leader tweeted she hoped to help Zuckerberg “understand the challenges #MLK faced from disinformation campaigns launched by politicians,” adding that such campaigns “created an atmosphere for his assassination.”

Writing in The Post, Sherrilyn Ifill, the president of the NAACP Legal Defense Fund, raised additional alarms, saying she feared Zuckerberg is “ill-equipped” to address the threat of voter suppression. She cited the attempts by Russian agents during the 2016 election to divide Facebook users on issues of race, specifically targeting African American users, and she highlighted the possibility that a politician could try to discourage turnout among people of color.

In response, Facebook said Friday it plans to host Bernice King for meetings at its Menlo Park, Calif., headquarters next week. “Their perspectives are critically important and we are committed to continuing the ongoing dialogue,” Roberta Thomson, a spokeswoman for the tech giant, said about the reaction from civil rights leaders. “Our work is far from over.”

Free speech advocates, meanwhile, exited Zuckerberg’s speech with conflicting feelings — supportive of his clarion call for governments and private-sector companies to help users express themselves while questioning whether the tech giant’s policies meet its top executive’s own vision.

“He’s sitting and talking to American college students at Georgetown, but who’s he really talking to — it’s live-streamed around the world — is a global audience,” said Kate Klonick, a fellow at the Information Society Project at Yale Law School who is studying Facebook’s work. “I think, at the end of the day, that is a good thing.”

But Klonick said the reality is more complicated, pointing to the fact that some researchers feel Facebook “is not consistent” when it comes to enforcing its own rules.

Facebook maintains detailed policies prohibiting harmful content, including hate speech, terrorist propaganda and violent imagery. Rebecca MacKinnon, director of Ranking Digital Rights, a nonprofit research initiative at New America’s Open Technology Institute, said Facebook had been too opaque about how those standards are enforced. She pointed to her organization’s 2019 report, which found Facebook provided too little detail about content it removes at the requests of governments or third parties, including on the two other social services it owns, WhatsApp and Instagram.

“He glossed over a lot of issues that relate to how speech is organized, optimized, and moderated on the platform currently,” she said. “That has huge impact on society and on human rights.”

“I hope it pushes organizations and individuals and whomever to hold Facebook accountable on this,” added Jillian York, the director for international freedom of expression at the Electronic Frontier Foundation. “You talk the talk, and now you’ve got to walk the walk.”