At 2:18 AM on Aug. 26, a long-distance bus carrying 37 passengers collided with a tanker loaded with highly flammable methanol on a Chinese highway in Shanxi Province. Both vehicles burst into flames, killing 36 passengers. Pictures of the accident began to circulate on Sina Weibo, the most popular Chinese micro-blogging site that is similar to Twitter, which is banned in China. Through social media, Chinese expressed their condolences to the families of the deceased. But soon the attention of Weibo users was drawn not to images of the accident itself but to a certain individual who had shown up at the crash scene.

Shortly after the tragedy, Yang Dacai, chief of the Shanxi provincial work safety administration, was caught grinning widely amid the wreckage. As Weibo users tried to figure out who this strangely smiley official was, pictures of Yang wearing luxury watches went viral. Following a now predictable path of online outrage in China, Weibo users rallied to launch against Yang what is locally called a “human-flesh search,” the online collaboration of Chinese to uncover information about a person, often in order to expose corrupt officials or other moral transgressors. Yang was quickly dubbed “the smiling brother,” and his laughing visage became September’s most comical Internet meme.

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Like other authoritarian regimes, the Chinese Communist Party considers freedom of speech perilous to its rule. For its 280 million Chinese users, Weibo is an online space where they can enjoy a modicum of free expression. Although the service faces constant interference by China’s army of online censors, vigorous debate still occurs on Weibo’s margins. Most importantly, the authorities at times appear to see the utility in allowing the masses to check some of the most flagrant abuses of power at the local level.

One day after the Shanxi accident, Sina Weibo users posted five photos of Yang wearing five different luxury watches, including a $63,000 Vacheron Constantin and a $10,000 Rolex. Many netizens questioned how a government worker who would have not been making more than $15,000 a year could afford so many expensive watches on his public salary. In a nation struggling with rampant local corruption, Yang soon acquired another nickname: “watch brother.”

On Aug. 29, Yang apologized for his unfortunate behavior at the scene of the accident. “In fact I was not smiling at that time,” he wrote on his Weibo account. “My facial expression was a little relaxed. What I did was just to make my colleagues feel more comfortable.” Yang reiterated that he bought these five luxury watches with savings accumulated over a 10-year period.

However Yang’s explanation did not dispel suspicion. On Aug. 30, Sina Weibo detectives found photos of Yang sporting another four luxury watches. On the same day, the Shanxi provincial discipline committee told state news media that it would launch an investigation of the watch brother and publicize the result of the inquiry. On Sept. 21, Yang was relieved of his position and accused of serious discipline violations.

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Yang is not the first Chinese official who was dismissed after cyber scrutiny. In December 2008, Zhou Jiugeng, head of the land bureau of Nanjing, said he would punish those real-estate developers who dared to sell their houses at a below-cost price. In a country gripped by real-estate fever, Zhou’s speech triggered angry responses all over the country. Soon he became the target of a human-flesh search; photos of Zhou that had been posed online were pored over by Internet sleuths. Netizens honed in on Zhou’s $16,000 $ Vacheron Constantin watch, luxury car and cigarettes. Eventually, he was placed under investigation and was later sentenced to 11 years in prison on a bribery conviction.

The Chinese government has publicly acknowledged the country’s graft problem. But using online fervor to bring down corrupt individuals can be a dangerous exercise. On Sept. 24, China Digital Times, a website run out of the University of California, Berkeley, reported that searches for the phrase “watch brother,” had been blocked on Sina Weibo. What was at first acceptable appears now to be a little too sensitive, especially as China is facing a delicate generational power shift in the coming weeks.

Despite hopes of catching corrupt local officials, stability is the utmost priority of the Chinese government. “With a once-a-decade political transition coming, the propaganda officials dislike seeing too many social pressures being aired on Sina Weibo,” says Zhan Jiang, a social-media professor at Beijing Foreign Studies University. “The whole [smiling-brother] event is nothing but a farce. Our conventional scrutiny mechanism has totally lost its efficiency and credibility. Only with the help of the new media can we find corrupt officials.”

Hu Xijin, editor of the Global Times, a newspaper that is part of the Communist Party-run People’s Daily group, lamented the political reality that has led to the rise in human-flesh searches of officials: “This event reflects the pathetic truth that our government’s credibility is disappearing very quickly,” he wrote on Sina Weibo. “The government should do something to change this.”

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That‘s easier said than done. And for all its power, Weibo can be used as an anti-graft weapon only when the government allows it to function in such a manner. “The microblogging site has other limitations,” says professor Zhan. “When we observe officials wearing watches, belts and glasses or using certain cigarettes, we can get clues about their possibly corrupt lifestyles. But we cannot look into every official. To some extent, the ‘watch brother’ is just unlucky compared with his corrupt colleagues who have not been discovered.”

Still, for every scandal that lights up Weibo, another one quickly takes its place. On Sept. 21, the same day when news trickled out of “smiling brother’s” dismissal, the Chinese social-media sphere was titillated by renewed interest in last year’s story of Wang Xiangui, an official from the local taxation bureau of Guiyang in southern China, who lost his cell phone. His flirtatious texts with seven mistresses circulated again on Sina Weibo in late September, making his case one of the most popular topics on the microblog site for days. Wang, married and in his forties, sent numerous texts to his consorts. “Where shall we meet tonight?” went one of his few G-rated messages. “Shall we book a room or just see each other in your home?” In the unrelenting news cycle, this year’s smiling brother had been outdone by last year’s texting husband.

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