President Joe Biden has signed a bill to ban TikTok, starting a nine-month countdown until the social media app’s Chinese parent company ByteDance will be forced to sell it or have it be removed from US app stores.

The proposed ban has generated furor on Capitol Hill — and online — since it first passed the House as a standalone bill last month.

TikTok has not actively pursued any buyers (despite former Treasury Secretary Steven Mnuchin, among others, having expressed interest) and is now vowing to challenge the ban in court.

“We believe the facts and the law are clearly on our side, and we will ultimately prevail,” TikTok said in a statement. “The fact is, we have invested billions of dollars to keep US data safe and our platform free from outside influence and manipulation.”

There has already been a revolt from users over First Amendment concerns. Last month, the social media app told its users to call their members of Congress in protest of the new bipartisan bill, arguing that a ban would infringe on their constitutional right to free expression and harm businesses and creators across the country.

Teens and older people alike reportedly pleaded with congressional staff, saying they spend all day on the app. Creators posted on TikTok urging their followers to do the same. Some offices decided to temporarily shut down their phone lines as a result, which meant that they couldn’t field calls from their constituents about other issues either.

Lawmakers in both parties didn’t take kindly to the impromptu lobbying frenzy. Some characterized it as confirmation of their fears that the Chinese-owned app — which is already banned on government devices — is brainwashing America. The overrun phone lines were merely “making the case” for the bill, Rep. Chip Roy (R-TX) wrote on X.

The White House has backed the bill from the beginning, reportedly providing technical support to legislators when they were drafting it (even as Biden’s reelection campaign has started using TikTok for voter outreach).

It’s not clear whether the ban will survive legal scrutiny. A federal court recently overturned a Montana law that sought to ban TikTok. Though legislators have argued that it is narrow in scope and would not amount to a total ban on TikTok that would violate the First Amendment, some legal experts believe otherwise.

“In my view, this loaded gun is a ban in all but name, and banning TikTok is obviously unconstitutional,” said Ramya Krishnan, a staff attorney at the Knight First Amendment Institute at Columbia University. “This ban on TikTok is materially the same [as the Montana ban] in all the ways that matter.”

Is a TikTok ban unconstitutional?

The constitutional law here appears straightforward: Congress can’t outright ban TikTok or any social media platform unless it can prove that it poses legitimate and serious privacy and national security concerns that can’t be addressed by any other means. The bar for such a justification is necessarily very high in order to protect Americans’ First Amendment rights, Krishnan said.

Lawmakers argue that the bill under consideration isn’t actually a total ban. Rather, it would enact a new authority to ban apps in “narrowly defined situations” when they are controlled by a foreign adversary, New Jersey Rep. Frank Pallone, the ranking Democrat on the Energy and Commerce Committee, said before the committee in March. He compared the bill to historical efforts to prevent foreign ownership of US airwaves due to national security concerns.

“It is no different here, and I take the concerns raised by the intelligence community very seriously,” he said.

Other House lawmakers have criticized TikTok for attempting to portray the bill as a total ban.

But legal experts say that an indirect ban may still be unconstitutional under the First Amendment. Civil society groups including the American Civil Liberties Union and the Center for Democracy and Technology (CDT) wrote in a recent letter to federal lawmakers that jeopardizing access to TikTok — “home to massive amounts of protected speech and association” — also “jeopardizes access to free expression.” There are also arguably less restrictive and more effective means of protecting any national security interests at stake in this bill, they asserted, considering the Chinese government could continue to access Americans’ data in other ways.

“This bill would functionally ban the distribution of TikTok in the United States, and would grant the President broad new powers to ban other social media platforms based on their country of origin,” they said in the letter.

Many experts believe it is unlikely that the government will be able to meet the high standard to prove that TikTok poses privacy and national security concerns that can’t otherwise be resolved, said Kate Ruane, director of CDT’s Free Expression Project. Lawmakers have publicly cited concerns about the Chinese government using the app to spy on Americans and to spread propaganda that could be used to influence the 2024 presidential election.

Though TikTok has repeatedly insisted that it has never shared user data with the Chinese government nor been asked to do so, a former employee of ByteDance has alleged in court that the government had nevertheless accessed such data on a widespread basis for political purposes during the 2018 protests in Hong Kong. And in December, TikTok parent company ByteDance acknowledged it had fired four employees who accessed the data of two journalists while trying to track down an internal leaker.

“TikTok is Communist Chinese malware that is poisoning the minds of our next generation and giving the CCP unfettered access to troves of Americans’ data,” Rep. Elise Stefanik (R-NY) said in a statement. “We cannot allow the CCP to continue to harness this digital weapon.”

However, national security experts have also questioned the rationale behind a ban. Mike German, a former FBI special agent and fellow at the Brennan Center for Justice’s Liberty and National Security Program, told Al Jazeera that, like many American apps, TikTok collects data on its users that a foreign government could theoretically use for its own hostile purposes. But those governments could just as well buy Americans’ data on a legitimate open market, where the sale of that data remains unrestricted.

And even if lawmakers did provide more evidence of national security concerns, it’s still not clear that the ban would pass legal muster.

Courts have already applied strict scrutiny to previous attempts to ban TikTok. A federal judge blocked the Montana TikTok ban — which also imposed a financial penalty on TikTok and any app store hosting it each time a user accesses or is offered the ability to access the app — before it was scheduled to go into effect in November.

Montana lawmakers justified the ban as a means of protecting the privacy interests of consumers in the state. But US District Judge Donald Molloy wrote in his ruling that the law overstepped the Montana legislature’s powers and left “little doubt that Montana’s legislature and Attorney General were more interested in targeting China’s ostensible role in TikTok than with protecting Montana consumers.”

Former President Donald Trump also twice tried to ban TikTok via executive action, only for courts to strike down his proposal both times. However, he recently changed his tune, arguing that banning TikTok would benefit Meta CEO Mark Zuckerberg and Facebook, which he referred to in a post on his social media platform Truth Social as a “true enemy of the people.”

Banning TikTok won’t solve lawmakers’ underlying concerns

Comprehensive digital privacy legislation is the only way lawmakers can truly address the privacy and national security concerns they’ve raised about TikTok, Ruane said.

“That would be a better path forward,” she said.

Her organization, the Center for Democracy and Technology, has supported a bipartisan bill that passed a committee vote in 2022: the American Data Privacy and Protection Act. It included provisions requiring companies to allow consumers to consent to or reject the collection of their data, to allow consumers to download and delete the data being collected on them, to require consumers’ affirmative consent to share that data with a third party, and more.

It was the culmination of a decades-long effort to regulate the collection, use, and sale of consumer data, similar to the European Union’s regulatory efforts. It would have tasked the Federal Trade Commission and state attorneys general with enforcing the law and preempted the patchwork of privacy laws that have been enacted at the state level in the absence of comprehensive federal legislation.

However, the privacy bill stalled in Congress and was not reintroduced; Ruane said it’s unclear why. Now lawmakers have instead succeeded in passing a TikTok ban — without solving the underlying privacy concerns.

“This bill would fail to protect us from the many threats to our digital privacy posed by criminals, private companies, and foreign actors,” said David Greene, civil liberties director at the Electronic Frontier Foundation, before it was passed. “Comprehensive data privacy legislation is the solution we need — not bans of certain categories of apps.”

Update, April 24, 1:05 pm ET: This story, originally published March 9, has been updated multiple times, most recently with the news that Biden has signed the ban into law.