In late June, two days after Twitter put a fifth warning label on one of President Trump’s tweets, Sen. Ted Cruz tweeted he was joining Parler, calling it “a platform [that] gets what free speech is all about.”

The social media site, which has been likened to a conservative Twitter, is on a tear with people who say Twitter and Facebook are silencing conservative voices. In one week, it gained 1 million users, bringing its total to 2.8 million users by early July.

Some of its most prominent users are part of the conservative establishment. Trump’s former campaign director Brad Parscale is on Parler, as is Eric Trump, the president’s son, and White House press secretary Kayleigh McEnany. Conservative commentator Dan Bongino announced in mid-June he had taken an ownership stake in the company.

A crackdown by Twitter and, more reluctantly, Facebook, against messages from President Trump that the companies said violate their policies is fueling Parler’s rise. Parler bills itself as a place for “free expression without violence and a lack of censorship,” key words many conservatives have picked up as a rallying cry to promote the app online.

Parler chief executive and co-founder John Matze said the app welcomes all voices. But the company appears to cater to a right-wing base fed up with what they view as censorship on traditional social media sites.

“We initially attracted conservative users because they felt disenfranchised by other social media platforms,” Matze said in an email sent through a spokesperson.

But Parler is quickly discovering the limits of free expression. On June 30, Matze used Parler to explain its house rules, apparently frustrated with some of Parler’s new users testing the limits of its free-expression motto by posting pornographic images and obscenities.

Parler is facing the same evolution bigger social media companies have confronted for years — balancing free expression with creating safe and inviting online communities. Twitter early on referred to itself as “the free-speech wing of the free-speech party.” Facebook chief executive Mark Zuckerberg maintained through the company’s early years that it is not a publisher, but a neutral platform. Facebook is still a place for free expression, Zuckerberg said in a speech last year, but he acknowledged some speech that is harmful and infringes on others’ rights shouldn’t be allowed.

Online conversations are complicated. Facebook has a six-part document outlining its community standards. Twitter has eight separate sections under its set of rules that just oversee safety. Facebook and Google-owned YouTube pay tens of thousands of content moderators to review material on their sites and enforce their policies.

Sites that have operated on the fringe with lax rules and a strong stance that people should be able to say just about anything they want have often become platforms for hate, violence and vitriol, such as 8chan and Gab. Those sites are more susceptible to being shut down when their back-end providers decide not to support them. Last year, 8chan was knocked offline for three months by a server hardware provider after the site was condemned for allowing manifestos and live streams of deadly shootings to spread.

Henderson, Nev.-based Parler launched nearly two years ago with private investors who have grown over time to include Bongino and early bitcoin advocate Jeffrey Wernick. Wernick wrote a Fox News opinion piece in support of Parler this month, saying Twitter and Facebook are using “technology intended to liberate, instead to subjugate.”

The social media site didn’t burst into the spotlight until June. Twitter had labeled five of the president’s tweets with warnings. Trump retaliated by signing an executive order that opened the door for an Internet shield law to be reconsidered. Facebook announced it would start labeling posts from politicians who violate its policies. Republican politicians and pundits called out the companies, saying they were biased against conservatives.

Two Republicans on the House Judiciary Committee asked Parler last week to meet with the panel to discuss social media competition.

“Parler differentiates itself on the quality and features of its platform — namely, its commitment to not ‘censor or editorialize, share or sell user data,’ ” Reps. Jim Jordan (R-Ohio) and F. James Sensenbrenner Jr. (R-Wis.) wrote. “This commitment positions Parler in stark contrast to Twitter, which has made increasingly clear in recent weeks and months that only users who refrain from expressing certain unfavored political beliefs are welcome to fully participate on its platform.”

Twitter spokeswoman Katie Rosborough reiterated what the company has insisted for years, that it is not biased against any group.

“Twitter enforces the Twitter Rules impartially for everyone on our service around the world, regardless of their background or political affiliation,” she said.

Facebook has gone out of its way to accommodate conservative voices, notably Trump, The Washington Post found. Facebook left Trump’s controversial May and June posts unlabeled — including one that said “when the looting starts, the shooting starts” in reference to protests that erupted after the police killing of George Floyd. But after harsh criticism from civil rights advocates and its own employees, the company announced an updated policy that will allow it to label posts from public figures that violate its policies but that it deems “newsworthy.”

Facebook declined to comment. The company has previously maintained it is not biased against any group. “Our policies, and how we apply them, can have a huge impact, so we have a responsibility to apply them evenly, without favoring one side or another and without devaluing the principle of free expression,” Nick Clegg, the vice president of global affairs and communications at Facebook, wrote in a blog post about alleged bias last year.

Social media experts point out many conservative politicians, notably Trump, perform well on Twitter because the company rewards posts that get more attention. Trump’s account is among the most popular on Twitter, with more than 83 million followers.

Some users, including Matze, are calling for people to exit Twitter altogether, using the hashtag #Twexit on Parler. But it seems unlikely a sizable number of people will leave Twitter. Even the politicians promoting Parler online still have active Twitter accounts. And Parler has a long way to go if it wants to appeal to the masses across a broad political spectrum.

Twitter has 166 million monthly average users and Facebook has 2.6 billion each month. Parler says it has a total audience of 2.8 million users.

“I’m a big Twitter fan, but Twitter censors a lot,” said Christina Herrera, an antiabortion advocate and new Parler user who lives in Hayward, Calif. “Whatever they define as hate speech goes.”

She said she is watching Parler closely to see how it holds up its free-expression mantra, but is hopeful. Still, she doesn’t plan to leave Twitter, where most of the online conversation around her advocacy takes place. And she’s hoping more diverse voices join Parler.

“I would rather there be a mix,” she said. “No one wants just an echo chamber.”

Parler’s app and website mimics Twitter in some ways — a news feed shows recent updates from accounts that users follow, and much of it includes links to news articles or political statements. It has fewer personal updates or pictures than Facebook or Instagram. Users can make new posts, or “parleys,” or “echo” others’ posts, which works like a retweet on Twitter.

On Parler, new users are prompted to follow popular accounts, including Republican Sen. Rand Paul (Ky.) and far-right commentator Laura Loomer. People share news articles from right-leaning organizations including Breitbart News and the Daily Caller. Some decry rules for mandatory mask-wearing. There is a fair amount of discussion around calls to support the police and encouraging people to buy Goya products after its chief executive supported Trump.

Parleyers, as the company calls its users, also have more casual conversations; they discuss Bible verses, share recipes or devise ways to persuade Trump to join the app. (Trump’s campaign has a Parler account but the president does not.)

Parler’s Matze said the app has “broad ideological diversity” and recently gained some zoomers and Black Lives Matter supporters.

“You know @parler has been a success when you see how many liberal snowflakes have come here to reply to every parley Nazi & Racist,” a fan account for Trump posted on the site recently.

Although it has become the poster child for free expression online, Parler since its inception has had a long list of community guidelines that outline what it won’t allow, including obscenity, terrorist content and “fighting words,” or calls to incite violence.

Those standards were tested in late June when Matze, apparently frustrated with some of the company’s new customers, posted a response to complaints on Twitter from people who said they were banned on Parler.

“Here are a few basic rules we need you to follow on Parler,” he wrote. He added some bullet points building off the company’s existing guidelines, with more specificity, including, “When you disagree with someone, posting pictures of your fecal matter in the comment section WILL NOT BE TOLERATED.”

Some of Parler’s new users are testing the bounds of its free-speech doctrine. Beth Bourdon, a public defense attorney in Orlando who says she has leftist political views, joined along with a couple of friends to “show them what free speech is.”

Bourdon said she was banned from Parler without notice after she and some friends spoke up against many of the viewpoints on the site and she posted a photo that some could consider explicit.

Parler said it has brought on 200 volunteer content moderators. The company’s support team posted on Parler that it needed volunteers because it is “experiencing a high number of brigading attacks from individuals who wish to see us fail!”

Matze said he does not see any conflict between the company’s guidelines and promoting free speech.

“The purpose of the restrictions is to create a proper town square without people ruining it by violating it with speech not protected by the First Amendment or FCC guidelines, while still allowing everyone to illustrate their point without experiencing any ideological censorship,” he said in an email.

Parler’s guidelines attribute many of its rules to Federal Communications Commission regulations and Supreme Court decisions, but social media companies are actually subject to very few laws when it comes to material posted on their sites. A law called Section 230 shields them from liability for nearly everything their users post online. Trump and his supporters — including Cruz (R-Tex.) — have attacked that law recently, saying it gives social media companies too much free rein.

“That’s the irony — content moderation is always necessary,” said Daniel Kreiss, a media professor at the University of North Carolina at Chapel Hill. “Just depends where you draw the line.”