Edward Smart, father of abducted 14-year-old Elizabeth Smart, took a lie detector test over the weekend. Marc Klaas knows what he's going through.

Klaas' 12-year-old daughter, Polly, was abducted from her bedroom and killed in 1993, and he also had to take a lie detector test. Investigators said it's a natural path because most abductors are acquaintances or family members.

"The numbers inevitably lead you back home," Klaas said.

The Justice Department will not quote firm statistics in child abduction cases, saying they're too difficult to compile and that there is no database of such incidents.

But a Justice report put together 12 years ago said acquaintances were responsible for 27 percent of kidnappings, strangers were responsible 24 percent of the time, and family members 49 percent of the time.

Police said Edward Smart and other family members are not the focus of the investigation into last week's disappearance of the 14-year-old girl.

Elizabeth was allegedly taken from her bedroom at gunpoint. Her 9-year-old sister was in the room with her at the time. The younger girl said she didn't report the abduction to her parents for almost two hours because the man threatened her.

Salt Lake City Police Chief Rick Dinse said Tuesday that the investigation was looking at those who had access to the neighborhood or the house, although not necessarily a family member. He said investigators have received some promising leads.

The National Center for Missing and Exploited Children reports that the murder of an abducted child is a rare event, with about 100 such incidents per year.

At least one expert said factoring in statistics doesn't help the investigation.

"There's research ... that if a child is abducted and murdered the child will probably be murdered in under three hours. This research for all practical purposes is not useful," said Kenneth Lanning, a retired FBI agent who specialized in crimes against children for 20 years. He now heads up CAC Consulting _ named after the FBI's Crimes Against Children division.

Investigators "need to move quickly for a number of reasons, and this fatalistic idea that she was taken and murdered immediately isn't part of that," he said. "You wouldn't do anything different if it was a 1 in 10 chance or a 1 in a million chance."

While Lanning cautions against focusing on statistics, he said investigators should keep some probabilities in mind.

"One of the things we statistically know when you're dealing with a child abduction that it is usually someone who lives or works in the area. The probability that someone flew in from Memphis and abducted this girl would be low," he said.

(Copyright 2002 by The Associated Press. All Rights Reserved.)