ADULT SUPERVISION Landmark broadcast indecency decisions • 1969: Supreme Court says free-speech protections for broadcasters are narrower than those for publishers and pedestrians.   • 1978: Court upholds FCC ban on George Carlin's "seven dirty words" and other indecencies on radio, TV "when there is a reasonable risk that children may be in the audience."   • 1995: Appeals court validates a broader FCC indecency ban, but limits it to between 6 a.m.-10 p.m.   • 1997: Supreme Court strikes down law that criminalizes the sending of "indecent or obscene" material to minors online.   • 2000: Court invalidates part of 1996 law that relegated pornography on cable TV to late-night hours.

Industry executives and lawyers, speaking on the condition of anonymity, say such measures raise the stakes, putting them in a position of having to fight a fine even if they are inclined to pay. "The way the law reads now if you pay a fine, it's an admission," said one industry attorney. "Anyone who gets into a three-strikes situation knows they're headed for a revocation hearing, because the law doesn't permit any other result."

Broadcasters have always been held to a higher standard than other forms of media when it comes to material considered indecent. While courts have defended broad free-speech rights of print media, the government has argued -- and courts have backed -- the notion that tighter TV and radio restrictions are needed because publicly licensed broadcast airwaves pervade homes uniquely.

The basic tenet of these indecency regulations is to protect children from exposure to sexually explicit or other "patently offensive" material. As the laws have evolved, indecent material has been deemed a form of protected speech under the Constitution's First Amendment. But its broadcast is limited to the hours of 10 p.m. to 6 a.m., when children are least likely to see or hear it. Attempts to extend such rules to other hours and other forms of media have been knocked down by the courts.

Broadcasters and free-speech advocates argue that much has changed since the Supreme Court last looked at this issue head-on in the Pacifica case, when the court ruled that Mr. Carlin's monologue on a New York radio station was indecent. Since then, new media such as cable television and the Internet have proliferated.

"The only speakers in the marketplace that are subject to the indecency standard are the broadcasters," says Marjorie Heins, director of the Free Expression Policy Project in New York and author of a book on the topic titled "Not In Front of the Children." "The question is whether the Supreme Court will say, 'We've got so much else out there now that it's silly and unfair to subject broadcasters to this indecency standard.' "

Legal experts say that anyone affected by the regulations could contest them as unconstitutional, and that it wouldn't be long before the issue was back before the Supreme Court.

The court's guiding precedent, Pacifica, involved the midday airing of Mr. Carlin's riff on bad language, during which he repeatedly used words he said probably aren't OK to say over the public airwaves. In their 5-4 ruling the justices decided he was right. In particular, the court singled out the special nature of the public airwaves to invade "the privacy of the home where the individual's right to be left alone plainly outweighs the First Amendment rights of the intruder." The majority opinion, written by Justice John Paul Stevens, emphasized "the narrowness" of the ruling and said it "requires consideration of a host of variables."

It was a close call, and dissenting justices were strident in their rebuke. The majority's attempt "to impose its notions of propriety on the whole of the American people [is] so misguided, that I am unable to remain silent," wrote Justice William Brennan, joined by Justice Thurgood Marshall.

Since then, the high court has refused attempts to use this opinion to extend its protection-of-children argument to cable television and the Internet. In 1997, the court struck down a federal law seeking to protect children from pornography and other harmful material on the Internet. In the 7-2 decision, also written by Justice Stevens, the court noted the "emphatically narrow holding" in Pacifica, finding that its extension to the Internet would "suppress a large amount of speech adults have a constitutional right to receive." Three years later, the justices ruled 5-4 to strike down a federal law seeking to restrict adult programming to overnight hours if cable operators couldn't fully scramble the signal.

Even without the new law, another legal avenue opened in April 2003 for those who want to challenge indecency fines. In an unrelated ruling, a Washington appeals court decided that paying any FCC fine would allow a company to seek judicial review.

Write to Anne Marie Squeo at annemarie.squeo@wsj.com¹