Chinese Police Hunt Overseas Critics With Advanced Tech

For Chinese security forces, the effort is a daring expansion of a remit that previously focused on Chinese platforms and the best-known overseas dissidents. Now, violations as simple as a post of a critical article on Twitter — or in the case of 23-year-old Ms. Chen, quoting, “I stand with Hong Kong” — can bring swift repercussions.

Actions against people for speaking out on Twitter and Facebook have increased in China since 2019, according to an online database aggregating them. The database, compiled by an anonymous activist, records cases based on publicly available verdicts, police notices and news reports, although information is limited in China.

“The net has definitely been cast wider overseas during the past year or so,” said Yaxue Cao, editor of, a website that covers civil society and human rights. The goal is to encourage already widespread self-censorship among Chinese people on global social media, she said, likening the purging of critics to an overactive lawn mower.

“They cut down the things that look spindly and tall — the most outspoken,” she said. “Then they look around, the taller pieces of grass no longer cover the lower ones. They say, ‘Oh these are problematic too, let’s mow them down again.’”

Chinese security authorities are bringing new technical expertise and funding to the process, according to publicly available procurement documents, police manuals and the government contractor, who is working on overseas internet investigations.

In 2020, when the police in the western province of Gansu sought companies to help monitor international social media, they laid out a grading system. One criterion included a company’s ability to analyze Twitter accounts, including tweets and lists of followers. The police in Shanghai offered $1,500 to a technology firm for each investigation into an overseas account, according to a May procurement document.