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We (can’t) Chat: “709 Crackdown” Discussion Blocked on Weibo and WeChat

April 13, 2017

Toronto, ON – Researchers at the Citizen Lab, based at the University of Toronto’s Munk School of Global Affairs, published a report today that reveals how discussions about a nationwide government crackdown on rights lawyers and activists in China are censored on WeChat and Weibo, two of the leading social networks in China. The crackdown is dubbed “709 Crackdown” as the first enforced disappearances of targeted individuals took place on July 9, 2015, and has since affected over 250 Chinese rights lawyers, law firm staff, activists and their relatives. The researchers tested words from news articles from popular news websites and discovered 44 keywords related to the 709 Crackdown were blocked on WeChat. These keywords were also found filtered on the search function of Weibo. The majority of these keywords include references to the names of individuals targeted by the crackdown.

“WeChat blocks certain combinations of keywords related to sensitive topics such as the ‘709 Crackdown.’  When a message contains the words of a blacklisted keyword combination, it is silently filtered.  Neither the sender nor the intended recipient receive a notification that the message was censored.” – Jeffrey Knockel, Senior Researcher, Citizen Lab, Munk School of Global Affairs, University of Toronto

With 806 million monthly active users, WeChat is the dominant chat application in China and fourth largest in the world. Weibo, China’s Twitter-like service, has reached 313 million monthly active users, almost equal to that of Twitter. Both applications thrive on their huge user base in China and concerned citizens have taken to these popular platforms to advocate for individuals affected by the crackdown. But both platforms must also follow strict content regulations in China. On WeChat, censorship related to the 709 Crackdown is enabled specifically on users with accounts registered to mainland China phone numbers, a consistent pattern Citizen Lab has found in past research.

“These findings highlight the challenges and potential hindrances faced by individuals, NGOs, and the international community in conducting advocacy work related to the ‘709 Crackdown’ as well as many other politically-sensitive cases in China. While there is tremendous global effort to help Chinese rights defenders, many of these messages fail to reach domestic audiences in China due to information control practices on Chinese social media platforms.” – Lotus Ruan, Research Fellow, Citizen Lab, Munk School of Global Affairs, University of Toronto

In addition to keyword filtering, the researchers found evidence of image filtering related to the 709 Crackdown on WeChat, the first documentation of its kind on the app. The researchers documented image filtering on WeChat Moments, a WeChat feature that resembles Facebook’s Timeline where users can share text or image updates with their friends. The greater attention to Moments is possibly due to concerns about posts being spread to larger audiences and leading to mobilization. Similar to keyword filtering, censorship of images is only enabled for China accounts. The filtering is also not transparent.

“Our report serves as a reminder that for a large portion of the world, social media act as gatekeepers of what they can read, speak, and see. When they operate in a repressive environment like China, social media can end up surreptitiously preventing important political topics from being discussed.  Our finding that WeChat is also systematically censoring images as well as text opens up the daunting prospect of multi-media censorship and surveillance on social media.” – Ron Deibert, Director, the Citizen Lab, Munk School of Global Affairs, University of Toronto

The Citizen Lab, based at the University of Toronto’s Munk School of Global Affairs, has extensive experience uncovering Internet censorship practices through network measurement and reverse engineering techniques. Previous work has investigated censorship on WeChat Public Accounts, Sina Weibo, chat apps, video sharing sites and live streaming platforms used in China.


For media inquiries, contact:

Dena Allen
Public Affairs & Engagement
Munk School of Global Affairs
University of Toronto
Telephone: 416-946-0123
Mobile: 416-795-3902

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Title: We (can’t) Chat: “709 Crackdown” Discussions Blocked on Weibo and WeChat
Published By: The Citizen Lab, Munk School of Global Affairs, University of Toronto
Publication Date: April 13, 2017
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