A suspended University of Pittsburgh neurologist arrested in an undercover sex sting will spend at least a few more days in jail while a federal judge contemplates letting him out pending trial or keeping him behind bars because the government considers him a threat to children.

Dr. Wesley Farris II, 38, of Fox Chapel, a Pitt faculty member and nationally recognized expert on Alzheimer's disease, appeared yesterday in shackles and a jailhouse jumpsuit before U.S. District Judge David Cercone. Judge Cercone listened to nearly three hours of arguments before saying he'll take the case under advisement.

Dr. Farris is charged with arranging to have sex with a 10-year-old girl at the Quality Inn in Oakland on March 5.

But the girl didn't exist, and her "uncle," with whom Dr. Farris had negotiated the tryst, was an undercover U.S. Immigration and Customs Enforcement agent.

In the federal court system, a suspect must prove why he shouldn't be locked up pending trial. The burden of proof is on the defendant, not the government.

But to bolster their case, prosecutors called on James T. Clemente, supervisory special agent at the FBI Behavioral Analysis Unit in Quantico, Va., who is in town for a conference on forensic science.

Agent Clemente, a child molester profiler, testified that his knowledge of Dr. Farris's "elaborate" actions in securing a child for sex would categorize him as a preferential offender. That's someone attracted to children of a certain age, gender or body type.

Preferential offenders are considered among the most dangerous to the community, which is why Assistant U.S. Attorney Soo Song argued that Dr. Farris remain locked up.

But Dr. Farris's lawyer, Paul Boas, argued that extensive supervised release conditions, including GPS monitoring and house arrest at his parents' home in Virginia, are enough to protect the community.

Mr. Boas also said his client will undergo medical treatment in Pittsburgh and Virginia to control his sexual appetite for children. "If you're attracted to young children, it's like being gay," he said. "There's nothing you can do about it."

Judge Cercone said he'd rule after he reviewed a treatment plan for Dr. Farris and had a chance to read a bunch of supportive letters submitted by various doctors and professors on Dr. Farris's behalf.