Wichita ? The things serial killers take away from crime scenes are not meaningless mementos. Those who study the cases say such trophies are important in understanding how BTK may have gone years without satisfying his hunger to kill.

In the BTK case, the timeline of killing stretches to 1991, with gaps as long as eight years between the victims, and a 14-year reprieve between the last death and Dennis Rader’s arrest.

Experts agree that regardless of the time between a serial killer’s murders, fantasies can be satisfied with a glimpse of his trophies.

“That is why they take trophies and photos,” said Marilyn Bardsley, a serial killer expert who edits CourtTV’s online crime library. “They can try to recreate that thrill of dominating and killing somebody.”

Police haven’t said if they’ve confiscated anything from Rader’s house that may have belonged to a BTK victim. But over the years, BTK’s mailings to authorities and the media have included tokens from his victims’ homes.

“The way he was taunting police, he was reliving the killing from a long time ago,” said Steven Egger, a criminologist at the University of Houston-Clear Lake who wrote a book on serial murderers, “The Killers Among Us.”

The souvenirs killers take from their dead allow them to relive their actions in their mind. It’s often a sexually gratifying experience.

Still, Bardsley said the enjoyment such trophies could bring was no replacement for actually killing again.

“That thrill wears off,” she said.

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