Willard Case: Search For Dna Clues It Took Nearly 18 Months. One Suspect Was Cleared. Lab Results Pointed To Arthur Bomar, Police Say.

Arthur Jerome Bomar Jr. was getting agitated. Sitting in a boxy room on the ground floor of the Delaware County Courthouse, the burly Bucks County man was playing a cat-and-mouse game with criminal investigators.

It was Oct. 15. Bomar, a paroled murderer, had been brought in from Camp Hill Prison, where he had spent the previous month beginning a three-to-seven-year sentence for a series of thefts.

But it was not theft that interested the detectives. It was the mystery that had haunted law-enforcement officials in the suburbs for more than a year: the rape and murder of Aimee Willard.

They were eager to charge Bomar with the slaying of the 22-year-old college athlete, a police officer's daughter killed on June 20, 1996, after being abducted from an off-ramp on the Blue Route. The detectives had what they felt was good evidence, both circumstantial and scientific. Early DNA tests had pointed toward Bomar.

But the prosecutors wanted more.

Over the next six weeks, investigators would use methods old and new to get the final elements needed to charge Bomar with killing Willard, a crime he denies any part of. They saw a moment of weakness in their suspect and tried to coax a confession.

At the same time, 300 miles away, scientists at a state police lab worked through each painstaking step of the DNA fingerprinting process, seeking conclusive evidence that the DNA found in semen taken from Willard's body was Bomar's.

The prosecutors in the Delaware County District Attorney's Office were in no hurry to bring a charge, sources said.

Bomar, 38, wasn't going anywhere. He was off the streets. Why not be patient and wait for the final DNA evidence to come back from the lab?

That gentle tug-of-war between prosecutors and detectives had been going on for a while when, on Oct. 14, prison officials told county authorities that Bomar had been found with a sheet around his neck. They called it a suicide attempt, though it was unclear whether he had intended to kill himself.

``We thought he might be in a psychologically weak moment,'' a law-enforcement source said.

So, the next day, they hauled him in for questioning. Sources said Bomar seemed ready to say something. At one point, he put his hand over his face and banged the table. But he stopped short.

``He became more interested in listening than talking,'' said an investigator who described how Bomar probed detectives on how much they knew about his alleged connection to Willard.