Google's decision to filter sensitive topics from Web searches in China is a major triumph for the regime's campaign to have the Internet censor itself, observers said Thursday, amid mounting criticism of the move.

However, scholars who study the Internet in China said free speech advocates still had room for optimism.

While China's grip on Web content appears to be tightening, communist authorities can't stop the overall trend toward access to more information and greater transparency, they said.

Mountain View, Calif.-based Google Inc. said its decision to launch a sanitized version of its famed search engine using China's ".cn" suffix was aimed at reaching China's massive Internet audience. It defended the move as a trade-off.

The new site, launched on Wednesday, omits independent Web sites from searches about human rights, Tibet and other topics sensitive to Beijing. Instead, users are directed only to Web sites espousing the government's views on such issues.

One prominent human rights advocate, U.S. Congressman Chris Smith, R-N.J., said it was "astounding" that Google, whose company motto is "Don't Be Evil," would cooperate with such censorship "just to make a buck."

"Many Chinese have suffered imprisonment and torture in the service of truth — and now Google is collaborating with their persecutors," said Smith, who has called for legal sanctions against U.S. technology companies that aid Chinese Web censorship.

Amnesty International said such cooperation clearly curtailed freedom of expression and information, calling Google's policy "short-sighted."

"Agreements between global corporations and the Chinese authorities have entrenched Internet censorship as the norm in China," the group's secretary general, Irene Khan, said from the World Economic Forum in Davos, Switzerland.

Despite the criticism, Google may have little cause for worry in the long-run. Similar complaints against Yahoo! and Microsoft Corp.'s MSN.com for submitting to China's censorship rules have so far failed to gel into any serious consumer or legal action against them.

Smith has invited all three companies to testify at a Feb. 16 hearing to examine how U.S. Internet companies operate in China.

John Palfrey, executive director of Harvard University's Berkman Center for Internet and Society, called Google's move "another step in a long series of steps that the Chinese government is taking to control the information environment."

But while the new site "puts to test its corporate motto," Google should take credit for avoiding privacy issues by refusing to locate its email and blogging functions on Chinese servers, he said.

Google had to set up a filtered version of its search site if it wanted business opportunities in China, including access to Chinese servers and inexpensive programming expertise, said Xiao Qiang, director of the China Internet Project at the University of California, Berkeley.

"It's not that much of a surprise," Xiao said.

However, both he and Palfrey agreed that the Internet remains a force for a more open society.

"Government censorship can slow down, but can't reverse this trend," Xiao said.