Mark Zuckerberg touted Facebook as a champion of “free expression” in a wide-sweeping speech, offering a staunch defense of the social media giant following several rocky years characterized by allegations against the platform of censorship and bias.

Speaking at Georgetown University on Thursday, the Facebook CEO invoked Frederick Douglass, Martin Luther King Jr and Black Lives Matter as a means of positioning Facebook as a champion for freedom of speech.

Zuckerberg defended the company’s decision to allow misinformation in political advertising on the platform, despite high-profile pushback against the policy.

“Given the sensitivity around political ads, I’ve considered whether we should stop allowing them altogether,” Zuckerberg said. “But political ads are an important part of voice – especially for local candidates, up-and-coming challengers and advocacy groups that may not get much media attention otherwise. Banning political ads favors incumbents and whoever the media covers.”

And he also seemed to brazenly rewrite the site’s beginnings, which were reportedly as a “hot or not” game for Harvard students to play, as a platform to share perspectives after the beginning of the Iraq war.

“I remember feeling that if more people had a voice to share their experiences, then maybe it could have gone differently,” he said. “Those early years shaped my belief that giving everyone a voice empowers the powerless and pushes society to be better over time.”

The CEO addressed Facebook’s attempts to enter the Chinese market, saying the company was unable to overcome China’s strict censorship. And he seemed to take a swipe at competitor platform TikTok, the Chinese video sharing app recently gaining huge popularity.

“I wanted our services in China because I believe in connecting the whole world, and I thought maybe we could help creating a more open society,” Zuckerberg said.

“I worked hard on this for a long time, but we could never come to agreement on what it would take for us to operate there,” he said. “They never let us in.”

Zuckerberg said the company now has 35,000 people working on platform security and that the company’s security budget is larger than $5bn – greater than the entire company’s revenue when it went public in 2013.

Zuckerberg’s address was met with swift, and fierce, criticism.

Not-for-profit organizations pushed back against a number of Facebook policies highlighted on Thursday, including those around hate speech and voter suppression. When discussing discriminatory speech, Zuckerberg repeatedly stressed his commitment to “free expression” and said he feared “potentially cracking down too much”.

“Mark Zuckerberg made clear today that he is not only doubling down on a business model that corrupts our democracy, but also fundamentally lacks an understanding of how civil rights, voter suppression, and racism actually function in this country,” said Rashad Robinson, the president of digital anti-hate group Color Of Change.

“Zuckerberg is co-opting civil rights history to justify Facebook policies that undermine our democracy,” said Vanita Gupta, the president of the Leadership Conference on Civil and Human Rights. “Hard to imagine MLK and Frederick Douglass, who he just invoked, supporting FB’s move to protect politicians who rely on misinformation and race-baiting for electoral gain.”

Zuckerberg’s reference to Facebook as the fifth pillar of democracy drew criticism from journalists. The Facebook CEO represents “the antithesis of free expression”, said John Stanton, the co-founder of the Save Journalism Project, in a statement.

“He’s thrown pennies at programs to ‘help’ journalists that, in actuality, are little more than PR stunts intended to provide cover as he puts countless journalists out of work, strips the industry to the bone, and reaps billions in ad revenue,” Stanton said.

Facebook’s policies on allowing misinformation in political advertising have been the subject of intense debate in recent weeks, following the platform’s refusal to take down a Donald Trump campaign ad that made misleading statements about the Democratic presidential candidate Joe Biden.

Facebook has increasingly come under scrutiny as the 2020 elections near, with a number of candidates calling for the breakup of the social media giant.

In an effort to highlight the consequences of the policy, the Democratic senator and presidential candidate Elizabeth Warren published her own misleading advertisement on the social media network.

Many of these issues may be addressed when Zuckerberg testifies next week at a congressional hearing over Libra, Facebook’s new cryptocurrency.

“Look, we know we’re doing a very good job of making everyone angry,” Zuckerberg said.