Emmanuel Jean Pierre is an aspiring writer who plans to release her first young adult novel later this year. And, for now at least, he’s a mail carrier for the US Postal Service who’s hungry for a regular creative outlet.

And for that he turns to TikTok, where he is known as Manny the Mailman and is a rising star in the online community known as #mailtok, a hashtag with 24.5 million views.

Jean-Pierre, who is from Morristown, New Jersey, has attracted 215,500 followers on the video app where he posts from his mail truck during lunch breaks most days. The videos cover topics ranging from how to spot spam to the moment a colleague had to deliver a package of live snakes.

“There are a lot of people who don’t know anything about the post office other than that we deliver the mail,” he said. “This becomes something different that shakes up my schedule.”

It’s also something Congress is making increasingly difficult, as government workers like Jean-Pierre are caught in the middle of a geopolitical fight between the United States and China over digital surveillance and foreign control of the media that now reaches into the millions. of people daily.

People who view TikTok as a national security threat have worked for years to limit the Chinese-owned video app’s reach on their driving of data from Americans and concerns about who in China have something to say about the content. The US military has banned TikTok on government-owned devices and urged troops to delete it even from personal phones. As of last month, all federal workers are prohibited from having TikTok on their work phones.

But some searches on TikTok reveal a different reality: Some government employees really like to post there and haven’t stopped doing so.

Army pilots post videos from inside flying helicopters. Park rangers talk about the wonders of nature. An air traffic controller dissects a near miss on an airport runway. And foreign service officers recruit future diplomats from underrepresented groups.

Their use of TikTok indicates how difficult it can be to enforce the latest restrictions on the app or any new restrictions politicians may propose.

“TikTok is a good audience for climate change,” said Peter Kalmus, a climate scientist at NASA’s Jet Propulsion Laboratory, who stressed that he was speaking for himself, not the agency.

He has amassed 253,800 followers on TikTok after posting just 22 videos. He opened his account last year after he was arrested in an act of civil disobedience outside a Chase Bank office for their investments in fossil fuels. The first video of him has received 1.3 million views.

Kalmus, like Jean-Pierre, uses a personal phone to post and doesn’t claim to speak on behalf of his agency, but the track record of federal restrictions has left federal workers and contractors wondering how long they can keep using TikTok. without consequences

In some places, using a personal device is not enough to get around TikTok’s restrictions. Students at some public universities are prohibited from using the app on campus networks, as a result of orders from state governors.

Kalmus said it would be a shame if the restrictions were extended.

“It is exactly the audience that needs to hear about climate change,” he said. “They are more prepared to hear about climate change than the Twitter audience. They are younger. It doesn’t feel so polarized.»

He said he’s concerned about TikTok’s Chinese ownership, but doesn’t think he has anything on his personal phone to be ashamed of. And he said that there is compensation.

«It still looks like it’s possibly worth the risk to get to the climate hearing,» he said.

The fight for the future of TikTok has pitted its Chinese parent company, ByteDance, and its American investors against foreign policy hawks who criticize its ties to China. The app is in talks with the Biden administration about new security measures, but so far there is no agreement and media investigations into TikTok have continued to turn up examples of privacy bugs.

Caught in the middle are government workers who, more than others, live at the whims of legislators. Federal employees have also been prime targets for hacking attempts, including a massive data breach revealed in 2015 that officials attributed to China.

It’s unclear if any federal agency is enforcing the latest ban related to government-owned devices. The No TikTok on Government Devices Act gave the White House Office of Management and Budget 60 days to come up with guidelines, and it has about a month before that deadline. The office declined to comment.

The office of Sen. Josh Hawley, R-Mo., who sponsored the new law, did not respond to a request for comment on how it will be enforced. This week, he revived legislation proposing a complete national ban on TikTok.

It’s not known precisely how many federal workers use TikTok, but certain hashtags show the breadth of its popularity. In addition to #mailtok, there is #rangertok, #foreignserviceofficer, #borderpatrolagents and others for different jobs and agencies.

John Sullivan said he had never posted on TikTok until last summer when he was working for the US Forest Service in Colorado’s Arapaho National Recreation Area.

“I’m 35 years old, so I don’t know anything about TikTok,” he said. (TikTok doesn’t publish exact data on the ages of users, but it has long been skewed toward the young.)

Then one slow day, a 22-year-old colleague suggested recording a video and together they created an educational message about the dangers of toxic algae found in Colorado. Sullivan used a cucumber as a pointing device and began calling himself the Cucumber Ranger.

“Every time we had some free time, we would go around, I would put on my uniform and cap, we would go out and shoot a video. Our job was recreation, and a lot of it was informing the public,” she said.

Sullivan said they used their personal phones and were careful not to use hashtags that implied endorsement by the Forest Service. But the hashtag #rangertok shows that he has a lot of company among federal employees. (The hashtag has 40 million views on TikTok, though many of those are from videos posted by state and local park rangers.)

The government is well practiced in banning technology when it comes to hardware, such as telecommunications components made by the Chinese company Huawei, or software if it is highly specialized, as in the aerospace industry.

But banning a social media app is a different project, especially when it’s available in a web browser.

Many videos of government workers are informative and provide experience outside of the usual channels—for example, a postman explaining why a house might get jumped on a delivery route if a vehicle is clogging a mailbox. Others offer advice on how to apply for federal jobs that are hard to get, even in the Foreign Service.

Public relations staff at some federal agencies said they had no plans to interfere with what federal workers were doing on their own.

“Those TikTok users are speaking in their personal capacity,” said Emma Duncan, a spokeswoman for the Federal Aviation Administration, which employs air traffic controllers.

Sullivan, who worked at the Forest Service, said he enjoyed using TikTok and might use it again for future government work, but said it wouldn’t be a big loss for him if he faced restrictions. He said that he remembers the heyday of MySpace.

“At first, it would be a loss, but the way I see social media working, a few months from now, a new social media app would take its place,” he said.