May 19 (Bloomberg) -- The U.S. Supreme Court upheld a federal law aimed at those who advertise or solicit child pornography, rejecting contentions that the measure will chill free-speech rights.

The justices, voting 7-2, said the so-called pandering provision doesn't criminalize protected speech and is clear enough to pass constitutional muster. The provision was enacted as a part of a broader 2003 measure targeting child pornography.

``Offers to provide or requests to obtain child pornography are categorically excluded from the First Amendment,'' Justice Antonin Scalia wrote for the court. Justices David Souter and Ruth Bader Ginsburg dissented.

The ruling restores one of two charges against a Florida man who admitted possession of sexually explicit images of children. The court upheld a provision that lets prosecutors seek a conviction even when sexually explicit images may be computer generated and might not involve actual children. The Bush administration said the pandering ban, though used sparingly, helps dry up the market for child pornography.

The pandering provision bars soliciting or offering images in a way that ``reflects the belief'' or ``is intended to cause another to believe'' that the depictions are illegal child pornography. The Atlanta-based 11th U.S. Circuit Court of Appeals had said the measure was vague and overly broad.

The law was a response to a 2002 Supreme Court ruling that struck down an earlier law. That statute had banned possession of movies or pictures that appeared to contain child pornography yet actually were generated with computers or with adults who look like minors.

`American Beauty'

The 2002 decision said the law raised legal questions about the award-winning movies ``Traffic'' and ``American Beauty,'' which depict sexual activity by teenagers.

Scalia said Congress had ``responded with a carefully crafted attempt to eliminate the First Amendment problems we identified.''

In dissent, Souter said the 2002 ruling established that only depictions of actual children ``trigger the concern for child safety'' that can overcome free speech concerns. Souter said the pandering provision went too far by punishing people for soliciting or offering images that might not depict minors.

``Without some demonstration that juries have been rendering exploitation of children unpunishable, there is no excuse for cutting back on the First Amendment,'' Souter wrote.

The case before the court concerned Michael Williams, who was sentenced to five years in prison after pleading guilty to pandering and possessing child pornography. His plea agreement let him challenge the constitutionality of the pandering ban.

Williams sent an undercover agent an e-mail claiming he had nude pictures of his 4-year-old daughter. He then posted a computer hyperlink to seven sexually explicit images of children as young as 5.

The case is United States v. Williams, 06-694.

To contact the reporter on this story: Greg Stohr in Washington at gstohr@bloomberg.net.

Last Updated: May 19, 2008 15:37 EDT