closely touching our most precious freedoms.”  Keyishian v.  Bd. of Regents of the Univ. of the State of N.Y., 385 U.S. 589, 603 (1967) (internal quotation marks and citation omitted); see also Bantam Books, Inc. v.  Sullivan, 372 U.S. 58, 66 (1963) ("The separation of legitimate from illegitimate speech calls for sensitive tools.”) (internal quotation marks and citation omitted).  Where the government draws content-based restrictions on speech in order to advance a compelling government interest, the First Amendment demands the precision of a scalpel, not a sledgehammer.  We believe that a public library’s use of the technology protection measures mandated by CIPA is not narrowly tailored to further the governmental interests at stake.  Although the strength of different libraries’ interests in blocking certain forms of speech may vary from library to library, depending on the frequency and severity of problems experienced by each particular library, we conclude, based on our findings of fact, that any public library’s use of a filtering product mandated by CIPA will necessarily fail to be narrowly tailored to address the library’s legitimate interests.  Because it is impossible for a public library to comply with CIPA without blocking substantial amounts of speech whose suppression serves no legitimate state interest, we therefore hold that CIPA is facially invalid, even under the more stringent standard of facial invalidity urged on us by the government, which would require upholding CIPA if it is possible for just a single library to comply with CIPA’s conditions without violating the First Amendment.  See supra Part iii. 3.  Less Restrictive Alternatives

The constitutional infirmity of a public library’s use of software filters is evidenced not only by the absence of narrow tailoring, but also by the existence of less restrictive alternatives that further the government’s legitimate interests.  See Playboy, 529 U.S. at 813 ("If a less restrictive alternative would serve the Government’s purpose, the legislature must use that alternative."); Sable, 492 U.S. at 126 ("The Government may . . . regulate the content of constitutionally protected speech in order to promote a compelling interest if it chooses the least restrictive means to further the articulated interest.").  As is the case with the narrow tailoring requirement, the government bears the burden of proof in showing the ineffectiveness of less restrictive alternatives.  “When a plausible, less restrictive alternative is offered to a content-based speech restriction, it is the Government’s obligation to prove that the alternative will be ineffective to achieve its goals.”  Playboy, 529 U.S. at 816; see also Reno, 521 U.S. at 879 ("The breadth of this content-based restriction of speech imposes an especially heavy burden on the Government to explain why a less restrictive provision would not be as effective . . . ."); Fabulous Assocs., Inc. v.  Pa.  Pub.  Util.  Comm’n, 896 F.2d 780, 787 (3d Cir. 1990) ("We focus . . . on the more difficult question whether the Commonwealth has borne its heavy burden of demonstrating that the compelling state interest could not be served by restrictions that are less intrusive on protected forms of expression.”) (internal quotation marks and citation omitted).