The World Wide Web contains a wide array of sexually explicit material, including hardcore pornography. Access to the Internet is widely available in homes, schools, and libraries across the country. Children may discover this pornographic material either by deliberately accessing pornographic Web sites or by stumbling upon them. Congress first attempted to protect children from exposure to pornographic material on the Internet by enacting the Communications Decency Act of 1996. The CDA prohibited the knowing transmission over the Internet of obscene or indecent messages to any recipient under 18 years of age. It also forbade any individual from knowingly sending over or displaying on the Internet certain 'patently offensive' material in a manner available to persons under 18 years of age. The CDA's regulation of indecent transmissions, and the display of patently offensive material see §223(d), ran afoul of the First Amendment. The CDA lacked the precision that the First Amendment requires when a statute regulates the content of speech' because, '[i]n order to deny minors access to potentially harmful speech, the CDA effectively suppressed a large amount of speech that adults ha[d] a constitutional right to receive and to address to one another.' Technology had no effective method for a sender to prevent minors from obtaining access to its communications on the Internet without also denying access to adults, its open-ended prohibitions embrace[d],' not only commercial speech or commercial entities, but also 'all nonprofit entities and individuals posting indecent messages or displaying them on their own computers in the presence of minors, and the CDA did not define the terms 'indecent' and 'patently offensive.' Congress went back to the drawing board and eventually the Child Online Protection Act was signed into law. COPA prohibits any person from 'knowingly and with knowledge of the character of the material, in interstate or foreign commerce by means of the World Wide Web, making any communication for commercial purposes that is available to any minor and that includes any material that is harmful to minors.' COPA applies only to material displayed on the World Wide Web. COPA covers only communications made 'for commercial purposes.' COPA restricts only the 'material that is harmful to minors.' COPA defines 'material that is harmful to minors' as 'any communication, picture, image, graphic image file, article, recording, writing, or other matter of any kind that is obscene or that-- '(A) the average person, applying contemporary community standards, would find, taking the material as a whole and with respect to minors, is designed to appeal to, or is designed to pander to, the prurient interest; '(B) depicts, describes, or represents, in a manner patently offensive with respect to minors, an actual or simulated sexual act or sexual contact, an actual or simulated normal or perverted sexual act, or a lewd exhibition of the genitals or post-pubescent female breast; and '(C) taken as a whole, lacks serious literary, artistic, political, or scientific value for minors.' ACLU (P) filed a lawsuit challenging the constitutionality of the statute. Ps feared that they would be prosecuted under COPA because some of that material 'could be construed as `harmful to minors' in some communities.' Ps claimed that COPA violated adults' rights under the First and Fifth Amendments because it (1) 'create[d] an effective ban on constitutionally protected speech by and to adults'; (2) '[was] not the least restrictive means of accomplishing any compelling governmental purpose'; and (3) '[was] substantially overbroad.' The District Court granted P's motion for a preliminary injunction, barring the Government, Ashcroft (D), from enforcing the Act until the merits of Ps' claims could be adjudicated. The District Court concluded that P had established a likelihood of success on the merits. COPA constituted content-based regulation of sexual expression protected by the First Amendment, the statute, under this Court's precedents, was 'presumptively invalid' and 'subject to strict scrutiny.' It was not apparent that COPA was the least restrictive means of preventing minors from accessing 'harmful to minors' material. D appealed. The Third Circuit affirmed. COPA's use of 'contemporary community standards' to identify material that is harmful to minors rendered the statute substantially overbroad. 'Web publishers are without any means to limit access to their sites based on the geographic location of particular Internet users,' the Court of Appeals reasoned that COPA would require 'any material that might be deemed harmful by the most puritan of communities in any state' to be placed behind an age or credit card verification system. The Supreme Court granted certiorari. The Supreme Court reversed, Ashcroft v. American Civil Liberties Union, 535 U. S. 564. On remand, the Third Circuit again affirmed, concluding, inter alia, that COPA was not the least restrictive means available for the Government to serve the interest of preventing minors from using the Internet to gain access to harmful materials. The Supreme Court granted certiorari.