Jailed for a Text: China’s Censors Are Spying on Mobile Chat Groups

Authorities scour private chats on messaging apps for blacklisted words, sensitive images

One night this September, construction supervisor Chen Shouli fired off a joke in a chat group.

“Haha,” he typed on his black iPhone 7, followed by an off-color wisecrack about a rumored love triangle involving a celebrity and one of China’s most senior government officials.

Four days later, he says, the police telephoned, ordering him in for questioning.

“I thought, I haven’t done anything wrong, have I? I’m law-abiding,” recalls Mr. Chen, a wiry 41-year-old. “So I went in. Once I arrived, they wouldn’t let me leave.”

Mr. Chen was locked in a cell for five days, he says. According to the police report, his comment on the WeChat messaging app was deemed “picking quarrels and provoking trouble,” a broad offense that encompasses gang fighting and destruction of public property and is punishable by detention without trial.

.. Zhu Shengwu was an intellectual-property lawyer in cases involving technology firms such as search engine BaiduInc. before taking on a free-speech case this year. He says that monitoring closed chats is akin to eavesdropping in someone’s home.

.. After he called President Xi Jinping a “baozi”—a steamed dumpling—in one WeChat post, and Chairman Mao a “bandit” in another, Mr. Wang was arrested, court records say. A local court in April sentenced him to two years in prison, a term that was reduced to 22 months after a retrial last month.

.. Mr. Guo says he wants to expose what he calls China’s “kleptocrats” and bring rule of law to the country.