Yahoo yesterday asked a court to dismiss a lawsuit accusing the Internet giant of abetting torture and abuse of pro-democracy writers in China.

Yahoo acknowledged releasing personal user information about the writers to the Chinese government, but said it had to comply with the country's lawful request and therefore cannot be held liable. Its 40-page response was filed yesterday in U.S. District Court for Northern California.

Advocacy groups view the suit as an important test case because it asks U.S. courts to punish corporations for human rights violations abroad. Internet companies such as Yahoo entering the booming Chinese market have had to alter user policies or allow censorship in order to comply with the country's laws.

The lawsuit was filed this spring by The World Organization for Human Rights USA on behalf of the imprisoned writers.

Two Chinese writers who used Yahoo's e-mail service to distribute their work are serving 10-year prison sentences. Shi Tao, a reporter and editor at Contemporary Business News in China, was arrested in November 2004 for publishing a document that the Chinese government considered a state secret and pleaded guilty. Wang Xiaoning, an author and editor of pro-democracy publications, was arrested in September 2002 and convicted for "incitement to subvert state power." Both are believed to have been abused and tortured while in custody, according to the lawsuit.

In its response, Yahoo argued that it did not "willfully" provide information about the online activities of the writers.

"Defendants cannot be expected, let alone ordered to violate another nation's laws," the company said in its filing. Chinese law requires anyone who receives a request for information as part of an investigation to comply and prohibits challenging such a request in the Chinese courts, Yahoo said in its filing.

Morton Sklar, the human rights organization's executive director, questioned whether the Chinese government's request for information was lawful. "But even if it was lawful in China, that does not take away from Yahoo's obligation to follow not just Chinese law, but U.S. law and international legal standards as well, when they do business abroad," Sklar said in a statement.

Yahoo spokeswoman Kelley Benander said in a statement that the company supported freedom of expression around the world and would continue to work with human rights organizations "on a global framework for technology companies operating in countries that restrict free expression and privacy."

"The real issue here is the plaintiffs' outrage at the behavior and laws of the Chinese government," she said. "The U.S. court system is not the forum for addressing these political concerns."