The new law, swiftly passed this week as part of an unrelated foreign aid package, will give the Biden administration another chance to dismantle an app it says the Chinese government can use to mass-gather Americans’ data and secretly shape their beliefs. But legal experts say there’s no certainty to how a new court challenge will be resolved.

Some legal scholars said the law could help the government avoid the fate of previous ban attempts because it no longer binds itself to ill-fitting case law, such as former president Donald Trump’s invoking of the International Emergency Economic Powers Act in 2020, and is crafted to guard against a First Amendment challenge by making the law less about content and more in line with the government’s restrictions on foreign ownership in industries such as banking and transportation.

But other experts said the law still trips over constitutional hurdles and fails to make a convincing case that the government could resolve its concerns only by forcing the sale of the app.

Susan Ariel Aaronson, a research professor at George Washington University who studies international trade and data rules, said the law also might raise questions among judges because it appears designed to penalize TikTok rather than focus on broader issues, such as data privacy and algorithmic transparency, that lawmakers have otherwise ignored.

“So if an American buys it, it’s all okay?” she said. “It makes no sense whatsoever. Does the problem exist or not?”

Biden’s signing of the law on Wednesday started a 270-day clock, which could extend to a full year, during which the government has ordered TikTok to be sold to a non-Chinese buyer. If ByteDance does not divest by then, the administration said it would work to block TikTok from Apple’s and Google’s app stores, effectively banning it nationwide as soon as January, a day before the presidential inauguration.

TikTok executives, however, have pledged to challenge the law in court and will probably push a judge to pause the law until the case is resolved, potentially tying it up for months — particularly if any appeal makes its way to the Supreme Court.

All of the action is likely to play out past November, when the election could redraw the composition of Congress and the White House — and possibly shift the government’s appetite for a drawn-out brawl.

“Rest assured: We aren’t going anywhere,” TikTok chief executive Shou Zi Chew said in a TikTok video on Wednesday. “We are confident, and we will keep fighting for your rights in the courts. The facts and the Constitution are on our side, and we expect to prevail again.”

Legal scholars said the new law showed that TikTok’s congressional critics, with help from administration officials, worked to distance themselves from the court-rejected orders of the past. The law also gives ByteDance more time to sell than the initial House bill’s provision of six months, potentially deflecting a TikTok claim that the law violates its rights of due process.

But the law could be weakened, others said, by the fact that the United States does not ban foreign ownership of U.S. media companies. The Federal Communications Commission voted in 2013 to relax its long-standing rule concerning foreign investment in radio and TV.

The arguments of TikTok’s critics in Washington that the app poses a grave national security threat due to its susceptibility to Chinese espionage and propaganda also could unwind in court due to lack of evidence, some legal scholars said. The government has yet to provide evidence that the Chinese government has used the app for either purpose, and TikTok has repeatedly disputed such claims.

Trump’s effort to ban the app in 2020 was overturned by federal judges who said the government had not shown sufficient proof of harm to justify violating Americans’ speech freedoms. Montana’s statewide TikTok ban was halted last year by a federal judge who said it carried a “pervasive undertone of anti-Chinese sentiment” and violated “the Constitution in more ways than one.”

Proponents of the new law hope it will withstand First Amendment challenges by arguing that Americans’ speech rights aren’t curtailed just because the app has new management.

Others said any court discussion of Project Texas, the $1.5 billion proposal TikTok made to the Biden administration to respond to concerns about the security of U.S. data, could end up undercutting arguments in favor of the law. During its years of negotiations with the Committee on Foreign Investment in the United States, a nine-agency group known as CFIUS, TikTok pledged to carve off the company’s U.S. operations into a domestic subsidiary subject to close federal oversight and control. But the government has yet to publicly outline why the proposal was not enough.

That will probably become a factor because judges run speech-related laws through a First Amendment test that asks whether they use the “least-restrictive means” to resolve the problem. The judge who overruled Trump’s 2020 ban, for instance, said it would have undercut more of Americans’ speech freedoms than was necessary to address the government’s concerns of a “hypothetical” threat.

“The United States has never blocked a communications platform of this size that so many Americans use, and the First Amendment and free speech are still huge hurdles for the government to overcome,” said Caitlin Chin-Rothmann, a researcher at the Center for Strategic and International Studies, a foreign policy think tank. “They haven’t explained to the public why Project Texas or comprehensive privacy legislation were not suitable alternatives.”

Sarah Bauerle Danzman, a senior fellow at the Atlantic Council who served as a CFIUS case officer for the State Department in 2019, said she believed the law offers a more airtight legal argument than the past federal and state cases. The argument from TikTok’s defenders that the law does not resolve the bigger concerns of data privacy and algorithmic transparency, she said, might prove irrelevant in court, where it will be assessed on its own merits.

“Judges should not be in the business of putting forward their most elegant solution to the problem,” she said. “They should be determining whether the path Congress chose is constitutional or not.”

The bigger issue for the government, she said, might be what to do if it wins in court and TikTok doesn’t comply. China has vowed to block any sale of its underlying algorithm using export-control rules, which could leave U.S. officials with a thorny choice: forcibly enact an unpopular ban, or back down and risk emboldening companies to believe the government is not as powerful as it claims.

“I suspect that’s really where the U.S. government is spending most of its time war gaming and strategic planning,” she said.

The courts have traditionally given broad leeway to the government’s concerns about national security, even over First Amendment claims. But the Supreme Court also held in 1965 that Americans had a constitutional right to receive foreign propaganda — setting a precedent that has yet to be reconsidered for the digital era.

“The First Amendment means that the government can’t restrict Americans’ access to ideas, information, or media from abroad without a very good reason for it — and no such reason exists here,” said Jameel Jaffer, executive director of the Knight First Amendment Institute at Columbia University.

The sponsors of the TikTok bill said the measure targets not just TikTok, but also any apps or websites “controlled by a foreign adversary,” such as China or Russia, that pose a “clear national security threat.” Legal experts said that broader language will strengthen the government’s defense in a constitutional challenge.

But TikTok and ByteDance are named specifically in the bill text, and an earlier version of the bill posted online was titled “TIKTOK.XML” — both of which legal scholars said they expect TikTok to raise in court.

Sen. John Thune (R-S.D.) and other lawmakers argued that a law targeting TikTok could be overturned because the Constitution prohibits “bills of attainder,” designed to punish a particular group or individual without a trial. The new law would also target other ByteDance apps popular in the United States, including the social network Lemon8 and video editor CapCut.

Some scholars said the government also could be tripped up by statements from members of Congress threatening to restrict TikTok due to its content.

Rep. Mike Gallagher (R-Wis.), who sponsored the TikTok bill before resigning last month to reportedly join the American defense contractor Palantir, has said TikTok is “digital fentanyl addicting our kids” and “brainwashing our youth” into supporting Hamas. Other lawmakers have said they were spurred to support the TikTok bill because they believed, without evidence, that the video app had improperly promoted pro-Palestinian videos, possibly to accomplish some Chinese political goal.

That sort of rhetoric could end up helping the company in court by supporting its claims that it had been singled out, said Jason Waite, an international trade and regulatory attorney at the law firm Alston & Bird. “TikTok will likely bring up their own words against them,” Waite said. “They’ll make hay of some of the rhetoric, which was very much targeting them.”

A separate provision in the bill restricting data brokers from selling Americans’ sensitive information to foreign buyers also could end up backfiring, Waite said, by showing that a less restrictive way exists to handle the government’s TikTok concerns.

“If we can pass laws to prevent the data from leaving the United States, couldn’t we just address the problem there?” he said. “If the government at this very moment is working on restricting the transfer of personal data, it begs the question about whether forcing a divestment is the least restrictive means.”

Some members of Congress have noted that the government could face a tough path to convince Americans that the legal morass is worth the cost. Only 38 percent of the U.S. adults polled by Pew Research Center last fall said they supported a federal TikTok ban.

“Many Americans, particularly young Americans, are rightfully skeptical. At the end of the day, they’ve not seen what Congress has seen,” Sen. Mark R. Warner (D-Va.) said Tuesday. “What they have seen, beyond even this bill, is Congress’s failure to enact meaningful consumer protections on Big Tech and may cynically view this as a diversion — or worse, a concession to U.S. social media platforms.”

But at least one prominent account has pledged to continue to use TikTok as the law winds its way through court: Biden’s reelection campaign, whose videos have received more than 3 million “likes.” A few hours before Biden signed the bill, the campaign posted a clip from a Biden event captioned with three smiling emoji.