Practically every U.S.-owned search engine has caved to the Chinese government's demands that they censor political Web sites in China. But none of them seem to agree on just what sites need censoring. Google, at times, blocks Chinese users' access to the BBC while Yahoo! permits it. Yahoo! sometimes filters out Voice of America--Google doesn't. And Microsoft removes entries from the Chinese version of Wikipedia from its results while every other search engine includes them--even the dominant Chinese search engine Baidu.com.

Confused? So are the search engines themselves, says Nart Villeneuve, a researcher at the University of Toronto's Open Net Initiative. In a study released on Wednesday, he points to the wild variation in search engine censorship in China as a sign that the Chinese government isn't handing companies a uniform list of censored sites but leaving them to guess at which sites are contraband.
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In a congressional hearing before the U.S.-China Economic and Security Review Commission on Wednesday, ONI director Ron Deibert held up the study as evidence of the complicity of U.S. firms in China's control of the media. Worse, he argued, they seemed to be doing more than China's dictators required to repress information.

"This kind of self-selection raises the prospect of anticipatory over-blocking, in which content not officially blocked by China ends up being filtered because of the eagerness of search engines," Deibert said.

Read the entire article here

Read the my testimony to US Congress here

Read Nart's research paper here