Legal experts say the episode highlights problems with the law that can make companies or individuals liable for linking to sites they do not control. And it has turned Google, whose business is built around a database of two billion Web pages, into a quiet campaigner for the freedom to link.

The church sent a complaint to Google last month, saying that its search results for "Scientology" included links to copyrighted church material that appears on a Web site critical of the church. Under the Digital Millennium Copyright Act of 1998, which was intended to make it easier for copyright holders to fight piracy, the complaint meant that Google was required to remove those links quickly or risk being sued for contributing to copyright infringement.

The site in question, Operation Clambake (www.xenu.net), is based in Norway, beyond the reach of the United States copyright act. The site portrays the church as a greedy cult that exploits its members and harasses critics. Andreas Heldal-Lund, the site's owner, says the posting of church materials, including some internal documents and pictures of church leaders, is allowable under the "fair use" provisions of internationally recognized copyright law.

When Google responded to the church's complaint by removing the links to the Scientology material, techies and free-speech advocates accused Google of censoring its search results. Google also briefly removed the link to Operation Clambake's home page but soon restored it, saying the removal had been a mistake.

At that point, according to Matthew Cutts, a software engineer at Google, it started developing a better way to handle such complaints. "We respond very quickly to challenges, and not just technical challenges but also these sort of interesting, delicate situations, as well," Mr. Cutts said.