Amnesty International is taking Yahoo to task over the company's role in the imprisonment of a Chinese journalist and is urging it to use its influence to get him released.

The human rights organisation launched an 'appeal for action' campaign on Tuesday, calling on people to write to Yahoo co-founders and directors Jerry Yang and David Filo requesting that they intercede on behalf of Shi Tao.

The journalist is serving a 10-year prison sentence after a Chinese court convicted him in April 2005 of divulging state secrets to foreigners. The California company played a part by turning over evidence in the form of email from Tao's Yahoo account to Chinese authorities.

Tao had sent email in April 2004 to a pro-China democracy website in New York regarding a Chinese government warning about possible unrest ahead of the 15th anniversary of the Tiananmen Square massacre.

Yahoo has said in the past that its decision to co-operate with the investigation is in line with its policy of abiding by the laws of the countries in which it operates, a position criticised by other groups, including Reporters Without Borders.

"Imprisoned for peacefully exercising his right to freedom of expression, a right entrenched in international law and the Chinese Constitution, Shi Tao is considered a prisoner of conscience," Amnesty International declared in its call to action, posted in its website. "Companies must respect human rights, wherever they operate. Yahoo’s business ethics are becoming questionable as a result of its role in assisting the Chinese government to sentence Shi Tao."

In its call to action web page, Amnesty International provides a model letter people can send to Yang and Filo, requesting that Yahoo:

  • use its influence to get Shi Tao released;
  • stop any actions that could undermine human rights in countries in which it operates;
  • ensure that all Yahoo units uphold human rights responsibilities;
  • develop an "explicit" human rights policy.

"I am alarmed that in the pursuit of new and lucrative markets, your company is contributing to human rights violations. Yahoo should urgently give consideration to the human rights implications of its business operations. The Universal Declaration of Human Rights calls upon every organ of society, which includes companies, to respect human rights," the model letter reads.

Yahoo has invested heavily in China in recent years, including $1bn (about £560m) last year to buy a stake in China-based and $120m (£68m) in 2003 to buy Hong Kong-based 3721 Network Software.

Yahoo didn't immediately reply to a request for comment about Amnesty International's campaign.

Amnesty International, based in London, has recently also criticised Google and Microsoft for complying with demands from the Chinese government to censor internet content on their websites.