The 3rd District US Court of Pennsylvania ruled that the law, which required public libraries to filter web content, violated the First Amendment right of free speech.
The Children's Internet Protection Act (CIPA) came into effect in the US on 20th April 2001, intended to protect minors from access to internet pornography. It obliges schools and public libraries where more than one computer is connected to the internet to use filtering software blocking images defined as "obscene", "child pornography" or otherwise "harmful to minors."
The law also requires adults to get permission to access such material. Libraries which fail to comply are barred from receiving federal funds.
After the law was enacted, the American Library Association and the American Civil Liberties Union sued the federal government claiming that the law violated consitutional provisions of free speech. The Pennsylvania District Court accepted their arguments and ruled that CIPA was "invalid" under the First Amendment.
The court also found that CIPA could not be enforced anyway, reasoning that "because of the inherent limitations in filtering technology, public libraries can never comply... without blocking access to a substantial amount of speech."
The Justice Department appealed the ruling. The Supreme Court will hear oral arguments in spring 2003.
CIPA can be found at:
www.filteringinfo.org/pdf/001218cipa.pdf