claim, we think that our findings of fact on public libraries, their use of the Internet, and the technological limitations of Internet filtering software, see supra Subsections ii.D-E, and our framing of the legal issue here, would allow the Supreme Court to decide the issue if it deems it necessary to resolve this case.  The doctrine of unconstitutional conditions “holds that the government ’may not deny a benefit to a person on a basis that infringes his constitutionally protected . . . freedom of speech’ even if he has no entitlement to that benefit.”  Bd. of County Comm’rs v.  Umbehr, 518 U.S. 668, 674 (1996) (quoting Perry v.  Sindermann, 408 U.S. 593, 597 (1972)).  In this case, the plaintiffs argue that CIPA imposes an unconstitutional condition on libraries who receive E-rate and LSTA subsidies by requiring them, as a condition on their receipt of federal funds, to surrender their First Amendment right to provide the public with access to constitutionally protected speech.  Under this theory, even if it does not violate the First Amendment for a public library to use filtering software, it nonetheless violates the First Amendment for the federal government to require public libraries to use filters as a condition of the receipt of federal funds.  The government contends that this case does not fall under the unconstitutional conditions framework because:  (1) as state actors, the recipients of the funds (the public libraries) are not protected by the First Amendment, and therefore are not being asked to relinquish any constitutionally protected rights; and (2) although library patrons are undoubtedly protected by the First Amendment, they are not the funding recipients in this case, and libraries may not rely on their patrons’ rights in order to state an unconstitutional conditions claim.  It is an open question in this Circuit whether Congress may violate the First Amendment by restricting the speech of public entities, such as municipalities or public libraries.  The only U.S.  Supreme Court opinion to weigh in on the issue is a concurrence by Justice Stewart, joined by Chief Justice Burger and Justice Rehnquist, in which he opined that municipalities and other arms of the state are not protected by the First Amendment from governmental interference with their expression.  See Colum.  Broad.  Sys., Inc. v.  Democratic Nat’l Comm., 412 U.S. 94, 139 (1973) (Stewart, J., concurring) ("The First Amendment protects the press from governmental interference; it confers no analogous protection on the Government."); see also id. at 139 n.7 ("The purpose of the First Amendment is to protect private expression and nothing in the guarantee precludes the government from controlling its own expression or that of its agents.”) (quoting Thomas Emerson, The System of Freedom of Expression 700 (1970) (internal quotation marks omitted)).  The Court has subsequently made it clear, however, that it considers it to be an open question whether municipalities acting in their capacity as employers