WASHINGTON, D.C.: The Supreme Court heard opening arguments in a landmark case that could determine the fate of free speech on the Internet. In the first time the electronic medium has come before the high court, the government is asking justices to uphold the 1996 Communications Decency Act, a never-enforced law making it a felony to put indecent words or pictures online. Justices spent much of the day trying to make a real-world analogy that would help them apply current law to the net. Justice Sandra Day O'Connor suggested the Internet could be considered a public arena, "much like a street corner or a park." Justice Stephen Breyer said the Internet "is very much like a telephone," adding that the law could "make large numbers of high school students across the country guilty of federal crimes" for having online conversations about their sexual experiences. Justice Antonin Scalia countered that in any context it's lawful for government to require that pornographic material be kept away from children. "We say "tough luck, you have to sell it in stores." In laying out the government case, Justice Department lawyer Seth Waxman argued that "The Internet threatens to give every child a free pass into the equivalent of every adult bookstore and every adult video store in the country." But the challengers, an attorney representing a free-speech coalition and companies including America Online and Microsoft, told the court the measure amounts to government censorship of adults' right to free speech. "The government cannot reduce the adult population to reading or viewing only what is appropriate for children," said lawyer Bruce Ennis. The decision, due out in June, will be a tough one for the nine justices. Although most of them have never explored the Web, its future depends on their choice.