U.S. Magistrate Judge Laurel Beeler in San Francisco issued a preliminary injunction at the request of a group of U.S. WeChat users, who argued the prohibitions would violate the free-speech rights of millions of Chinese-speaking Americans who rely on it. The app, which was supposed to disappear from U.S. app stores on Sunday, has 19 million regular users in the U.S. and 1 billion worldwide.

The ruling means that neither WeChat nor TikTok, another Chinese-owned mobile app targeted by President Donald Trump’s executive order, will become immediately unavailable in the U.S. Trump cited national security concerns in banning the apps, but TikTok Inc. and the WeChat users’ group have said the president is trying to bolster his re-election chances by attacking China and Chinese companies.

WeChat “serves as a virtual public square for the Chinese-speaking and Chinese-American community in the United States and is (as a practical matter) their only means of communication,” the judge wrote in the ruling, dated Saturday and released early Sunday. Effectively banning it “forecloses meaningful access to communication in their community and thereby operates as a prior restraint on their right to free speech.”

The judge found the government provided insufficient evidence of a security threat. “Certainly the government’s overarching national-security interest is significant,” she wrote. “But on this record — while the government has established that China’s activities raise significant national security concerns — it has put in scant little evidence that its effective ban of WeChat for all U.S. users addresses those concerns.”

The Department of Justice and Commerce Department didn’t immediately respond to requests for comment. The government is likely to appeal the ruling.

The ruling will probably survive if it’s appealed to the Ninth Circuit, said Carl Tobias, a law professor at the University of Richmond.

“Judge Beeler’s ruling seems very careful especially in clearly finding that plaintiffs have sufficiently satisfied the requirements for entering a preliminary injunction on the First Amendment claim,” Tobias said. “The judge also treats the weaker portions of both plaintiffs’ and the government’s arguments, especially the lack of evidence presented by the government, and finds that plaintiffs have the better of it.”

Michael Bien, an attorney for the U.S. WeChat Users Alliance, said the U.S. “has never shut down a major platform for communications, not even during war times.”

“There are serious First Amendment problems with the WeChat ban, which targets the Chinese American community and trampled on their First Amendment guaranteed freedoms to speak, to worship, to read and react to the press, and to organize and associate for numerous purposes,” he said in a statement.

The U.S. has claimed that WeChat is a threat because its owner, Tencent Holdings Ltd., is intertwined with the Chinese Communist Party, which can use the app to disseminate propaganda, track users, and steal their private and proprietary data. It’s a similar argument that the administration has used to target the TikTok app, while also forcing a sale of that app’s U.S. operations.

TikTok Delay

The U.S. government on Saturday delayed its plan to prohibit downloads of TikTok, the popular video-sharing app, after Trump said he approved Oracle Corp.’s bid for the U.S. operations of TikTok “in concept.” The TikTok ban was also set to go into effect Sunday, but the order has been delayed until Sept. 27. TikTok on Friday filed suit in Washington, D.C.

At a court hearing Saturday, Bien said the restrictions on WeChat are a far cry from the “narrowly tailored” measures that the government is required to impose so as not to unnecessarily curtail people’s constitutional rights.

Michael Drezner, a lawyer for the the government, said at the hearing that the anxiety and uncertainly U.S. WeChat users may experience because of the prohibitions doesn’t entitle them to an order halting the implementation of the restrictions. Their reliance on WeChat is the result of China’s ban on other social media, which has made WeChat the exclusive, Chinese government-controlled option for them to communicate with people in China, according to Drezner.

Drezner also noted the app will remain available for use by people who already have it on their phones, although its use will degrade over time because updates won’t be available. But Beeler responded that the ability for the app to function would be “essentially eviscerated.”

Beeler had rejected a request for a preliminary injunction on Friday, which the users had sought on the grounds that the executive order was too vague. The Commerce Department on Friday detailed which transactions with WeChat and its Chinese parent company won’t be allowed under the Aug. 6 executive order. The judge scheduled the hearing Saturday in response to a revived request from the users group.