A new document calls into question the extent of Yahoo's cooperation with Chinese authorities in the arrest and imprisonment of Chinese journalist Shi Tao, sentenced in April, 2005, to 10 years in prison for revealing state secrets.

An English translation of the Beijing State Security Bureau's Notice of Evidence Collection, issued to the Beijing Representative Office of Yahoo (HK) Holdings, says, "According to investigation, your office is in possession of the following items relating to a case of suspecting illegal provision of state secrets to foreign entities that is currently under investigation by our bureau. ..."

The translation of the notice was posted last week by The Dui Hua Foundation, a nonprofit human rights organization.

In congressional testimony in February 2006, Yahoo general counsel Michael Callahan denied that Yahoo knew the charge.

"When Yahoo China in Beijing was required to provide information about the user, who we later learned was Shi Tao, we had no information about the nature of the investigation," Callahan said. "Indeed, we were unaware of the particular facts surrounding the case until the news story emerged. Law enforcement agencies in China, the United States, and elsewhere typically do not explain to information technology companies or other businesses why they demand specific information regarding certain individuals."

In a blog post Sunday, Rebecca MacKinnon, assistant professor at the University of Hong Kong's Journalism and Media Studies Centre, noted the discrepancy between Yahoo's professed ignorance of the charge and the charge spelled out in the notice. "Now we know that when Callahan said 'We had no information about the nature of the investigation,' he was not telling the truth," she said.

MacKinnon said that this is significant because, as Joshua Rosenzweig, manager of research and publications for The Dui Hua Foundation, put it, "One does not have to be an expert in Chinese law to know that 'state secrets' charges have often been used to punish political dissent in China."

Shi Tao was an editor and reporter for Contemporary Business News, a Chinese newspaper. According to Human Rights Watch, he was detained in November, 2004 for revealing state secrets and subsequently formally arrested. The Chinese government charged him with taking notes on a government memorandum entitled "A Notice Regarding Current Stabilizing Work" and subsequently outlining the content of the memorandum in a pseudonymous Web posting to a discussion forum hosted in a foreign country.

Yahoo provided account information that prosecutors used to link Shi Tao's Yahoo e-mail account to the computer at the Contemporary Business News office associated with the pseudonymous posting, according to Human Rights Watch.

"We strongly disagree with the characterization of Mr. Callahan's testimony," said Yahoo spokesperson Jim Cullinan. "His testimony to Congress last year was accurate and forthright. In regards to the Shi Tao case, Mr. Callahan's testimony stated that Yahoo China did not know Mr. Shi's identity, and the Chinese government did not provide the facts surrounding the case or disclose that the nature of China's investigation was related to dissident activity. The document in question supports Mr. Callahan's testimony."

Yahoo and other Internet companies like Google and Microsoft have consistently stated that they are required to abide by the law in all countries where they do business. All three have asked the U.S. government to treat censorship as a trade barrier.

"We appeal to the U.S. government to do all it can to help us provide beneficial services to Chinese citizens lawfully and in a way consistent with our shared values," said Callahan in his testimony last year.

Shi Tao is eligible for release on Nov. 24, 2014.