WASHINGTON (CNN) -- The U.S. Supreme Court ruled Monday that a law aimed at banning sexually explicit material available to minors on the Internet is not unconstitutional simply because it relies on "community standards."
But the justices did not rule on several other aspects of the Child Online Protection Act, and sent the case back to an appeals court for further review.
The opinion says the government continues to be barred from enforcing the law until a Circuit Court rules in the case.
The law passed by Congress is the second attempt to shield children from online pornography. The first law passed in 1996 was declared unconstitutional because it violated the First Amendment's free speech guarantee.
This time the high court left the question of the constitutionality of the act unanswered.
In a majority opinion by written Justice Clarence Thomas, the court said only that the law's "reliance on 'community standards' to identify what material is 'harmful to minors' does not itself render the statute substantially overbroad for First Amendment purposes."
Thomas was joined in most portions of the fractured opinion by Justices William Rehnquist, Sandra Day O'Connor, Antonin Scalia, and Stephen Breyer. Three justices wrote separate opinions concurring in the conclusion. Only Justice John Paul Stevens dissented, saying the law should have been declared unconstitutional.
The Supreme Court has long held that one test of whether sexually explicit material may be banned is whether it violates local community standards. Free speech advocates have claimed that in the age of the Internet, when information is available everywhere, the producers of the material cannot and should not be required to ensure they do not offend the various standards of communities across the nation.
The opinion left room for the Third U.S. Circuit Court of Appeals to find the Child Online Protection Act (COPA) unconstitutional on other grounds.
"The court expresses no view as to whether COPA suffers from substantial overbreadth for reasons other than its use of community standards, whether the statute is unconstitutionally vague. ... Prudence dictates allowing the Third Circuit to first examine these difficult issues."
The Justice Department said it was "pleased" with the decision.
"Congress carefully drafted the law to put Internet pornography on the same footing as material offered for sale in bricks-and-mortar bookstores or convenience stores, where children are protected from inadvertent viewing because magazines are wrapped in brown paper or are kept behind the counters," said the department's chief spokeswoman, Barbara Comstock in a brief written statement.
"As the Child Online Protection Act undergoes further review, the Justice Department will take all available steps to support the act and keep our nation's children safe from viewing the pornography for sale on the Internet."
She made no mention of the limited reach of the ruling, or the continued hold on enforcing the law.
The case, Ashcroft vs. ACLU, was argued before the justices