Last month, though, the American Library Association found at least 200 instances since late 2001 in which police targeted libraries in a hunt for information.

In one case, the names of people checking out books on Osama bin Laden were requested.

Because Section 215 makes it illegal for anyone involved in a search to make it public, there was no way the ALA study could determine if the actions were Patriot Act-approved.

The responses were anonymous to protect librarians.