blocking software and alternative methods used by public
libraries to protect children from material harmful to minors.
Finally, there are other less restrictive alternatives to
filtering software that further public libraries' interest in
preventing patrons from unwillingly being exposed to patently
offensive, sexually explicit content on the Internet. To the
extent that public libraries are concerned with protecting
patrons from accidentally encountering such material while using
the Internet, public libraries can provide patrons with guidance
in finding the material they want and avoiding unwanted material.
Some public libraries also offer patrons the option of using
filtering software, if they so desire. Cf. Rowan v. Post Office
Dept., 397 U.S. 728 (1970) (upholding a federal statute
permitting individuals to instruct the Postmaster General not to
deliver advertisements that are "erotically arousing or sexually
provocative").


With respect to protecting library patrons from sexually
explicit content viewed by other patrons, public libraries have
used a variety of less restrictive methods. One alternative is
simply to segregate filtered from unfiltered terminals, and to
place unfiltered terminals outside of patrons' sight-lines and
areas of heavy traffic. Even the less restrictive alternative of
allowing unfiltered access on only a single terminal, well out of
the line of sight of other patrons, however, is not permitted
under CIPA, which requires the use of a technology protection
measure on every computer in the library. See CIPA Sec.
1721(b)(6)(C) (codified at 47 U.S.C. Sec. 254(h)(6)(C)), CIPA Sec. 1712
(codified at 20 U.S.C. Sec. 9134(f)(1)(A)) (requiring a public