The U.S. Supreme Court will consider the constitutionality of a federal law that expands the definition of child pornography in an effort to crack down on cybersex prowlers.

The high court will hear a First Amendment quarrel today and decide if two phrases in the PROTECT act of 2003 are unlawfully vague and overbroad. The court is expected to take the case under advisement after oral argument and issue its opinion before the end of its current term in June 2008.

The issue surfaced after Michael Williams pled guilty on two counts of child pornography: possessing the material and "pandering" (promoting) the images.

In an Internet sting operation, Williams offered sexually explicit pictures of his 4-year-old daughter to an undercover federal agent; authorities found 22 images of underage children on Williams' computer.

Following Williams' appeal, the 11th Circuit Court of Appeals overturned the pandering conviction, calling the PROTECT act's language "impermissibly vague and facially unconstitutional."

The pandering section of the PROTECT act — adopted by Congress as the Prosecutorial Remedies and Other Tools to End the Exploitation of Children Today Act — was the latest of several attempts by Congress to strengthen penalties for Internet predators.

In one of those attempts Congress passed an anti-pornography law that prohibited the creation of computer-generated images of children. The Supreme Court struck it down in 2002 for infringing on freedom of expression.

Juan Becerra, Salt Lake City FBI spokesman, said if the court upholds Williams' appeal it would take an arrow out of law enforcement's quiver. But, he said, "We're still going to go after these guys as hard and aggressively as before."

Becerra also said the Wasatch Front leads the nation in child pornography investigations, arrests and convictions.

"Pandering" specifically prohibits advertising, promoting, presenting or soliciting "any material or purported material in a manner that reflects the belief, or that is intended to cause another to believe, that the material or purported material" contains child pornography.

The controversy grows out of the two subjective phrases, "reflects the belief," and "intended to cause another to believe," which Williams claims are too vague and smother free speech. A person does not have to posses the unlawful material to be charged with pandering; merely describing it in a way that "reflects the belief" that one possesses it is enough.

Congress said such a strict law is necessary because "even fraudulent offers to buy or sell unprotected child pornography help to sustain the illegal market for this material."