The US Supreme Court has sided with a previous court injunction against a law intended to protect children from sexually explicit material posted online.
The Supreme Court said that the law was unconstitutional because less restrictive ways of shielding children, such as filtering software had emerged since the law was passed in 1998.
Opponents of the COPA argued it was overly broad and would in essence outlaw all adult-theme materials on the internet, including sex advice columns and sexual health-related information, as websites attempt to avoid fines and jail time.
The Supreme Court upheld the appeals court injunction against enforcing the Child Online Protection Act (COPA) of 1998, which allows for a fine of $50,000 (£27,000) a day and a six-month prison sentence for posting online materials that are "harmful to minors".
The Supreme Court's ruling sends the case back to the lower court to decide whether the law violates the First Amendment of the US Constitution.
The case that challenged the law, Ashcroft versus the American Civil Liberties Union (ACLU), pitted US attorney general John Ashcroft against the civil liberties group, representing several publications, including websites which include information on sexually transmitted diseases.
Filtering software, as well as a law against misleading domain names and a law establishing a child-safe dot-kids domain, are less restrictive ways to protect children from sexually explicit materials, argued Justice Anthony Kennedy. New technological methods may have improved filtering software since the law passed in 1998, Kennedy wrote.
"There is a serious gap in the evidence as to the effectiveness of filtering software," Kennedy wrote. "The technology of the internet evolves at a rapid pace."
Kennedy argued that filtering software was likely to be more effective than COPA because COPA does not protect children against websites published outside the US.
Civil liberties and other groups cheered the Supreme Court's ruling, which advocated that parents voluntarily use filtering software to protect children.
Grant Gross writes for IDG News Service