On Jan. 26, Chinese lawyer Xu Zhiyong was given a four-year prison term for “gathering a crowd to disturb public order.” The verdict in the high-profile trial of the founder of the New Citizens Movement, an alliance of activists promoting rule of law among other issues, underlines what the Chinese government fears most: organized social protest.

One of the more mystifying aspects of China’s communist party (CCP) is the extent and kind of criticism it allows. Chinese media are known to lambast government policies on censorship (paywall), pollution, and China’s alliance with North Korea. Criticism of the government is even more common (though admittedly fleeting) on Chinese social media—all of which gives China, and the CCP, a semblance of openness.

Yet, Xu, like many of those who have campaigned for goals that are shared by his government such as reduced pollution and corruption, has been quickly censured.

That’s because the threat Xu and the New Citizen’s Movement pose is the ability to organize. Since 2012, the group has been holding monthly dinners and discussions across as many as 20 Chinese cities. Small-scale demonstrations at government ministries in Beijing and elsewhere have further unnerved officials. The group’s manifesto, now scrubbed from Chinese websites, has specific aims such as improving China’s petitioning process and getting officials to disclose their financial assets.

The ability to organize large-scale demonstration is a common thread for groups that are repressed by the Chinese government, including the Falun Gong, Sichuan earthquake activists, popular bloggers, and even a Nu Skin cosmetics direct sales scheme. A study last year of Sina Weibo found that censors didn’t always wipe online comments criticizing the government but targeted those promoting social mobilization, regardless of the issue.

Indeed, one of Beijing’s charges against Xu is that he took advantage of public sentiment over certain social topics to incite unrest. An editorial (link in Chinese) in the state-owned Global Times justifies the verdict in terms of protecting the country against social upheaval, as in the Arab Spring or China’s own Cultural Revolution. This week, four other members of the group go on trial and another well-known activist, Hu Jia, has been detained.

For the CCP, the most dangerous aspect of the New Citizen’s Movement may be its more subtle appeal. The group is made up of thoughtful, educated Chinese who aren’t seeking revolution but a transition into a society governed by the rule of law and democratic principles—a message that appeals to many Chinese, even those who are wary of widespread social instability. Activists point out that this gradual process, what academics call “reform incrementalism” (paywall) has been successful elsewhere in East Asian societies like Taiwan and South Korea.

But as long as the CCP holds sway over China, groups that can mobilize a decent number of people should be prepared for a crackdown. Even as the party’s leader Xi Jinping moves to liberalize the financial sector and weaken the power of China’s giant state-owned industries, the one monopoly that seems destined to last is the government’s stranglehold over reform itself.