Efforts to shield children from pornography, obscenities and other materials inappropriate for young eyes continue to hit legal obstacles that raise questions about how much online smut is protected by First Amendment rights (search).

The Supreme Court earlier this month agreed to hear arguments over the 1998 Child Online Protection Act (search), a law that criminalized online transmission for commercial purposes of material harmful to minors. First-time violators face six months in jail and $50,000 in fines.

The case centers on whether preventing indecent material from reaching children via e-mail inboxes, pop-up ads and certain Web sites leads to censorship of legal material.

"The speech that you want to regulate here is speech that is OK for adults to get … yet at the same time, you want it to not be available to minors on the Internet," said Lee Tien, senior staff attorney for the Electronic Frontier Foundation (search). "This is fundamentally a real, real hard thing to do."

COPA and state obscenity laws allow communities to set local standards for what is offensive and to outlaw certain types of erotic materials that don't meet those standards. Solicitor General Ted Olson (search), who is arguing the government's case in court, has said that COPA creates a reasonable solution to the proliferation of online pornography.

But opponents of the law say that applying community standards to online material is difficult because Web sites are pervasive regardless of their point of origin. In other words, more conservative parts of the country could sue Web sites hosted in more liberal areas, claiming that the Web company's reach extends into their communities but doesn't meet local standards for decency.

In February 1999, a U.S. District Court in Philadelphia agreed with civil liberties groups, the content industry and Internet companies who argued that the law was unconstitutional; the U.S. government appealed the ruling to the U.S. Court of Appeals for the Third Circuit (search).

In June 2000, the appeals court also prevented COPA from going into effect and said it wasn't possible to apply to the Internet "contemporary community standards (search)" of material acceptable for children.

In May 2002, the Supreme Court upheld the injunction but said the standards question alone does not make the law unconstitutional, and sent the case back to the lower court for more review. The high court earlier this month agreed to review the case after the Third Circuit upheld its original ruling. It is expected to hear the case later this year or in the early part of next year.

Experts say the courts haven't gotten yet to the meat of the issue — community standards — and they're hoping that this time around, the Supreme Court will do just that.

"These are arguments we've been waiting for since 1998" since each of the lower courts' rulings were made on technical grounds, not merit, said Tim Johnson, spokesman for Rep. Mike Oxley, R-Ohio, a co-author of the COPA law.

"Obviously, we hope the future of the act is that it will finally be upheld by the Supreme Court," Johnson told Foxnews.com.

Robert O'Neil, director of the University of Virginia's Thomas Jefferson Center for the Protection of Free Expression (search), said he doesn't think it's been proven that community standards can't do the job effectively.

"There hasn't been any record developed … demonstrating the inapplicability or undependability of community standards," O'Neil said. "Until there is more evidence to that effect, I'm not sure there's going to be a majority of this court to strike it down."

But even those who say the law does more harm than good agree that something should be done to prevent children from getting a hold of pornography.

The Center for Democracy and Technology (search), the Electronic Frontier Foundation and the American Civil Liberties Union (search) support a less restrictive approach to preventing access by children, including placing more emphasis on educating parents to decide for themselves how to regulate what their children see.

The technology industry has introduced a myriad of tools to help parents, such as filters and green spaces that attempt to keep online smut at bay.

"The tools are still not perfect … but they're getting better," said Ari Schwartz, associate director for CDT. "We feel that if more time and effort were spent on helping parents and teachers understand how to use these tools, then you would create a good marketplace and get better tools out of the process."

But Oxley and the law's supporters argue that the technology industry has already had enough time to make inroads in this area but has not. They add that legislation is obviously needed.

"In five years, the tech industry has had an opportunity to address this and so far, we have not had a foolproof way to, in essence, put a brown paper bag over these sites," Johnson said.

COPA was Congress' second attempt to crack down on harmful material on the Internet.

Congress previously passed the Communications Decency Act of 1996 (search), whose Internet indecency provisions were struck down on First Amendment grounds by the Supreme Court in the 1997 decision ACLU v. Reno.

"We're going to get through this," Tien said. "Do we have the answers? No, but I think this next round is just another opportunity for [the courts] to clarify their thinking."