Child Online Protection Act
- Not to be confused with the Children's Online Privacy Protection Act, abbreviated "COPPA"
The Child Online Protection Act (COPA) was a law in the United States of America, passed in 1998 with the declared purpose of restricting access by minors to any material defined as harmful to such minors on the Internet. The federal courts have ruled that the law violates the constitutional protection of free speech, and therefore have blocked it from taking effect. As of 2009, the law remains unconstitutional.
The law was part of a series of efforts by US lawmakers legislating over Internet pornography. Parts of the earlier and much broader Communications Decency Act had been struck down as unconstitutional by the Supreme Court; COPA was a direct response to that decision, narrowing the range of material covered. COPA only limits commercial speech and only affects providers based within the United States.
COPA required all commercial distributors of "material harmful to minors" to restrict their sites from access by minors. "Material harmful to minors" was defined as material that by "contemporary community standards" was judged to appeal to the "prurient interest" and that showed sexual acts or nudity (including female breasts). This is a much broader standard than obscenity.
The federal government was enjoined from enforcing COPA by a court order in 1998. In 1999, the United States Court of Appeals for the Third Circuit upheld the injunction and struck down the law, ruling that it was too broad in using "community standards" as part of the definition of harmful materials. In May 2002, the Supreme Court reviewed this ruling, found the given reason insufficient and returned the case to the Circuit Court; the law remained blocked. On March 6, 2003, the 3rd Circuit Court again struck down the law as unconstitutional, this time finding that it would hinder protected speech among adults. The government again sought review in the Supreme Court.
On June 30, 2004, in Ashcroft v. American Civil Liberties Union, the Supreme Court upheld the injunction on enforcement, ruling that the law was likely to be unconstitutional. Notably, the court mentioned that "filtering’s superiority to COPA is confirmed by the explicit findings of the Commission on Child Online Protection, which Congress created to evaluate the relative merits of different means of restricting minors' ability to gain access to harmful materials on the internet." The court also wrote that it was five years since the district court had considered the effectiveness of filtering software and that two less-restrictive laws had been passed since COPA, one prohibiting misleading domain names and another creating a child-safe .kids domain, and that given the rapid pace of internet development those might be sufficient to restrict access by minors to specific material. The court referred the case back to the district court for a trial, which began on October 25, 2006.
In preparation for that trial, the Department of Justice issued subpoenas to various search engines to obtain Web addresses and records of searches as one part of a study undertaken by a witness in support of the law. The search engines turned over the requested information, except for Google, which challenged the subpoenas. The court limited the subpoena to a sample of URLs in Google's database, but declined to enforce the request for searches conducted by users; Google then complied.
On March 22, 2007, U.S. District Judge Lowell A. Reed, Jr. once again struck down the Child Online Protection Act, finding the law facially in violation of the First and Fifth Amendments of the United States Constitution. In addition to the plaintiffs ACLU et al, several witnesses testified in defense of first amendment rights on the Internet, including the director of the Erotic Authors Association, Marilyn Jaye Lewis.  Reed issued an order permanently enjoining the government from enforcing COPA, commenting that "perhaps we do the minors of this country harm if First Amendment protections, which they will with age inherit fully, are chipped away in the name of their protection." The government again appealed, and the case was heard before the Third Circuit.
On July 22, 2008, the 3rd U.S. Circuit Court of Appeals upheld the 2007 decision. 
- COPA is sometimes confused with COPPA, the Children's Online Privacy Protection Act, which remains in force and limits the ability of sites to offer services to those aged twelve and under without explicit parental consent.