China's WeChat runs "two-systems" censorship

China's top messaging app, WeChat, operates different censorship policies for accounts created within China and those set up outside the mainland, say researchers at the University of Toronto's Citizen Lab. They have also found that users are no longer being made aware when their messages are being censored. The researchers say it is the first systematic analysis of censorship and filtering on the app. Immutable identity Keyword-based filtering is enabled for WeChat accounts that are registered to mainland Chinese phone numbers. The platform blocks private messages containing certain words and phrases in one-on-one and group chats, but more commonly in the latter, Citizen Lab found. Users with accounts created in China can have their content censored even if they are posting from outside the country. But accounts set up outside the mainland, including in Hong Kong, do not face the same curbs. "The identity a user creates when they register for WeChat determines which system they will be under. This identity is immutable... They will always be locked into the same system," says Citizen Lab. "The idea that such a system is possible is a serious concern for future transnational Chinese citizens - some of whom might in the future even become citizens of other nations." The app's owner, Tencent, has also stopped notifying users if their messages are intercepted, making its filtering operations more opaque, says the study. Triggers Citizen Lab study found that 174 words and expressions, including "Free Tibet" and "ISIS Crisis", triggered censorship. The highest percentage of keyword blocks comprised messages relating to the 1989 Tiananmen Square massacre. Other themes that led to blocking included high-profile corruption cases and references to pro-democracy movements. Tencent did not respond directly to the specific findings of the Citizen Lab report. But it in a response provided to TechCrunch website it said: "Tencent respects and complies with local laws and regulations in countries we operate in to provide a safe and reliable communications ecosystem for our users."