We find that there are plausible, less restrictive alternatives to the use of software filters that would serve the government’s interest in preventing the dissemination of obscenity and child pornography to library patrons.  In particular, public libraries can adopt Internet use policies that make clear to patrons that the library’s Internet terminals may not be used to access illegal content.  Libraries can ensure that their patrons are aware of such policies by posting them in prominent places in the library, requiring patrons to sign forms agreeing to comply with the policy before the library issues library cards to patrons, and by presenting patrons, when they log on to one of the library’s Internet terminals, with a screen that requires the user to agree to comply with the library’s policy before allowing the user access to the Internet.  Libraries can detect violations of their Internet use policies either through direct observation or through review of the library’s Internet use logs.  In some cases, library staff or patrons may directly observe a patron accessing obscenity and child pornography.  Libraries’ Internet use logs, however, also provide libraries with a means of detecting violations of their Internet use policies.  These logs, which can be kept regardless whether a library uses filtering software, record the URL of every Web page accessed by patrons.  Although ordinarily the logs do not link particular URLs with particular patrons, it is possible, using access logs, to identify the patron who viewed the Web page corresponding to a particular URL, if library staff discover in the access logs the URL of a Web page containing obscenity or child pornography.  For example, David Biek, Director of Tacoma Public Library’s main branch, testified that in the course of scanning Internet use logs he has found what looked like attempts to access child pornography, notwithstanding the fact that Tacoma uses Websense filtering software.  In two cases, he communicated his findings to law enforcement and turned over the logs to law enforcement in response to a subpoena.

Once a violation of a library’s Internet use policy is detected through the methods described above, a library may either issue the patron a warning, revoke the patron’s Internet privileges, or notify law enforcement, if the library believes that the patron violated either state obscenity laws or child pornography laws.  Although these methods of detecting use of library computers to access illegal content are not perfect, and a library, out of respect for patrons’ privacy, may choose not to adopt such policies, the government has failed to show that such methods are substantially less effective at preventing patrons from accessing obscenity and child pornography than software filters.  As detailed in our findings of fact, the underblocking that results from the size, rate of change, and rate of growth of the Internet significantly impairs the software filters from preventing