For Wang Fei, the journey from high-flying advertising executive to jobless national hate figure began with an extramarital affair. His disgrace was absolute and immediate. Rarely is there any other outcome after one becomes a target of the "human flesh search engine."

This is the name given to the Internet-powered manhunts that have achieved notoriety across China this year. A human flesh search engine is where thousands of volunteer cybervigilantes unite to expose the personal details of perceived evildoers and publish them on the Web.

The consequences for those on the receiving end often transcend the virtual world and can include loss of employment, public shaming, even imprisonment. Conversely, the most voracious "flesh hunters" are widely seen as the online equivalent of lynch mobs. Many of the participants are too young to draw a loose comparison with the "public criticisms" and purges of the Cultural Revolution more than 40 years ago.

In Wang's case, his wife posted a series of blog posts expressing her devastation over her husband's infidelity and then leapt to her death from their 24th-floor apartment. Almost instantly, an online mob--the human flesh search engine--enraged at Wang's philandering, exploded into life.

Within days, photographs of Wang appeared on numerous Internet forums alongside his phone numbers, address and national ID number. Slogans were painted on his front door. One read: "A blood debt must be repaid with blood."

His lawyer said Wang was forced to resign from advertising agency Saatchi & Saatchi after its Beijing office became subject to abuse and that he was harassed by strangers in the street.

Wang is by no means alone. The human flesh search engine first shot to prominence in 2006, thanks to the macabre actions of Wang Jue, a nurse from Heilongjiang Province.

Now known as the "Kitten Killer of Hangzhou," Wang Jue uploaded a video of herself crushing a kitten to death under her high heels. People identified her location by studying the backdrop to the video and traced the offending pair of stilettos to a purchase made on eBay. The stilettoed murderess eventually issued a public apology, blaming her actions on her devastation following her failed marriage. Both she and the cameraman who recorded the kitten killing lost their jobs.

The Internet is often criticized for allowing, even encouraging, anonymity. Alternate identities are constructed in virtual worlds like Second Life that bear little or no relation to those that create them. Sheltered behind screen names, people post hateful rants on blogs, upload outrageous videos to YouTube and slander authors on Amazon. For better or worse, the human flesh search engine strips away the layers of digital anonymity.

This year, the human flesh search engine rose to the peak of its powers during periods of nationalistic fervor and grief, namely the Olympic-torch relay protests that followed the unrest in Tibet and the earthquake in Sichuan in May. A number of individuals who openly challenged the sense of unity important to so many Chinese were named and shamed, resulting in teary online apologies and, in one case, an arrest.

Collaboration between the online masses to meet a common goal is known as "crowd sourcing" in the U.S. But in China it is the sheer scale of the operation--recruits can be enlisted from an online population of more than 250 million--and the people's "unusually high enthusiasm" that makes the human-flesh-search-engine phenomenon unique, says Xujun Eberlein, an American Chinese author and commentator.

A host of political and cultural factors lie behind this hunger for uncovering hidden identities. They range from what Eberlein terms the "intellectual underemployment" of many educated, working Chinese to the prevalence in China of a "culturally based inquisitiveness that does not have any strong tradition of respecting privacy."

Eberlein also points out that righteousness is one of the five virtues in the Confucian tradition and that "righteous people tend to take matters into their own hands."

Add to these motivations the fact that despite the authorities' strict control over online political content there is a lack of privacy laws in China to prevent people's private details being published on the Web, and the growth potential of the human flesh search engine is apparent.

This may be about to change, largely due to the publicity generated by a high-profile lawsuit filed by Wang Fei, the advertising executive who fell victim to a human flesh search engine after his wife's suicide.

Wang is suing two leading Internet portals that hosted the hunt for his identity as well as an individual for defamation and violating his privacy. The defense argues that since much of Wang's information was already available online, it is not guilty of any wrongdoing.

The lawsuit was filed in March. A verdict has yet to be announced.

Some new privacy regulations have already been set in motion. A law was proposed in August that seeks a three-year jail sentence for officials who are found to leak personal data that could be snapped up by the human flesh search engine.

But any attempt to regulate the Internet in China to prevent further privacy violations is likely to prompt raucous debate.

Two years ago, the government flirted with the idea of introducing a real-name registration system for bloggers and Internet forum users, only to retreat under a barrage of public anger.

The real-name system is already in place on major Web sites in South Korea, but there are many in China who doubt such a move could work in an authoritarian state where dissent is often punished. Xujun Eberlein says that although new privacy laws would help combat the ugly side of the Web manhunts, the price would still be too high.

"There is [a Chinese] adage describing such a situation: You want to kill the rat, but you also have to worry about smashing the treasured dish it is in. The treasured dish ... here is the freedom of speech," she says.

Skeptics of stricter Internet laws point to the positive effects of the human flesh search engine. It can help to tackle corruption by identifying dishonest officials when the media is unable, or reluctant, to report and law enforcement authorities turn a blind eye.

The Internet's important role in media freedom was on display during the aftermath of the Sichuan earthquake in May, when public clamoring for more information loosened constraints over the state-run media, albeit temporarily.

Forget about online privacy laws, argues Eberlein, and concentrate on morals.

"One problem with China's situation is that it lacks moral leaders," she says. "There is a more urgent need for the Chinese people to establish new moral standards or return to traditional ones, such as Confucianism, rather than adding restrictions on the use of the Internet."

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