An Indiana lawyer urged the Supreme Court yesterday to allow the state to enforce "traditional notions of what constitutes public decency" and prohibit nude barroom dancing.

But the attorney for erotic dancers and adult businesses told the court it "is not the business of the state" to decide what is protected art and what may be banned -- "to determine which is trash and which is value." The First Amendment, said the lawyer, Bruce J. Ennis Jr., "leaves that to the individual."

The court heard oral argument yesterday in Barnes v. Glen Theatre, in which the justices are being asked to decide whether Indiana's public indecency law violates the free speech rights of dancers. The state says the dancers must wear pasties and G-strings to comply with the law.

A federal appeals court disagreed, ruling that the nude dancing at issue was "inherently expressive," conveying an emotional message of eroticism and sensuality, and was, therefore, entitled to First Amendment protection.

Defending the state law, Indiana Deputy Attorney General Wayne E. Uhl told the court that Indiana prohibits people walking naked down the street, or strolling naked into a bar, and should also be allowed to prohibit the same conduct by those who dance there.

He said the dancing was not speech because it did not communicate a message -- an argument that Justice John Paul Stevens suggested would allow Indiana to prohibit tap dancing without violating the First Amendment.

Even if it is speech, Uhl said, the restriction is like prohibiting actors from smoking marijuana in a play -- an act that the state could still prohibit even though the play is protected by the First Amendment.

Ennis told the court that dance is "one of the oldest forms of human communication and is inherently expression of emotions and ideas." Since the conduct is inherently expressive, he said, the fact that it involves nudity should not remove the normal First Amendment protections that apply.

"The statute isn't addressed to dancing at all," said Chief Justice William H. Rehnquist. "It's addressed to public nudity."

"Nobody is stopping her from dancing," said Justice Antonin Scalia. "They have stopped her from going about nude . . . just as they have murder laws in Indiana whether they're dancing or not."

Ennis emphasized that the state has power to prohibit the dancing at establishments that serve liquor or in places where unwilling viewers will be exposed to it, and could enact zoning restrictions to limit where the dancing takes place.

The court has suggested in the past that nude dancing is "not without" First Amendment protections, but the justices have never squarely decided the issue. Although speech that is obscene is not shielded by the First Amendment, Indiana in this case has conceded that the dancing would not be considered obscene under the standards set out by the high court.

Uhl initially seemed to tell the court that some nude dancing, like opera, would still be allowed because, unlike nude barroom dancing, it involved expression. Later he said the statute imposed a "blanket ban" on nude dancing.

A number of justices had seemed troubled about how -- if some nude dancing is allowed and some is banned -- that choice would be made. Scalia asked whether it was "the good taste clause of the Constitution. How does one draw that line, between Salome and the Kitty Kat Lounge?" he asked.

"Are you really confident that we could make the distinction between dancing that is not part of a larger form of artistic expression and dancing that is artistic expression?" asked Justice Anthony M. Kennedy. "We would be really striking out in a very new direction, wouldn't we?"

Justice David H. Souter said the dancers in this case may believe that "the medium" -- nude dancing -- "is the message."

Justice Sandra Day O'Connor questioned Uhl about how he could argue that music is expression protected under the First Amendment -- as it is under a 1989 court ruling -- but dance is not. "Explain that," she said. "You think some of the music played in the {1989} case conveyed a message?"

When Uhl said in response to her question that the state could not prohibit sale of a videotape that showed the same dancing, O'Connor asked: "Why can you ban the real thing and not the videotape of it?"