including limitations on the technology that software filtering companies use to gather

and review Web pages, limitations on resources for human review of Web pages, and the

necessary error that results from human review processes.

Because the filtering software mandated by CIPA will block access to substantial

amounts of constitutionally protected speech whose suppression serves no legitimate

government interest, we are persuaded that a public library's use of software filters is not

narrowly tailored to further any of these interests.  Moreover, less restrictive alternatives

exist that further the government's legitimate interest in preventing the dissemination of

obscenity, child pornography, and material harmful to minors, and in preventing patrons

from being unwillingly exposed to patently offensive, sexually explicit content.  To

prevent patrons from accessing visual depictions that are obscene and child pornography,

public libraries may enforce Internet use policies that make clear to patrons that the

library's Internet terminals may not be used to access illegal speech.  Libraries may then

impose penalties on patrons who violate these policies, ranging from a warning to

notification of law enforcement, in the appropriate case.  Less restrictive alternatives to

filtering that further libraries' interest in preventing minors from exposure to visual

depictions that are harmful to minors include requiring parental consent to or presence

during unfiltered access, or restricting minors' unfiltered access to terminals within view

of library staff.  Finally, optional filtering, privacy screens, recessed monitors, and

placement of unfiltered Internet terminals outside of sight lines provide less restrictive

alternatives for libraries to prevent patrons from being unwillingly exposed to sexually

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