Obtained by ABC NewsBy MATTHEW MOSK, ABC News

(WASHINGTON) -- When the lead investigator in the manhunt for escaped murderer Lester Eubanks came to Washington, D.C., this summer to meet with U.S. Marshal Service top brass, he made a special diversion to the behavioral sciences unit, whose offices are deep in the bowels of the agency’s sprawling headquarters.

“We were looking for a different perspective – a real outside-the-box thinker – who could possibly give us insight,” Deputy U.S. Marshal David Siler explained.

Siler had spent years dissecting the shards of evidence surrounding the 1965 murder of 14-year-old Mary Ellen Deener, Eubanks’ 1973 escape from an Ohio prison and his series of false identities to remain at large. ABC News profiles this case in our podcast, "Have You Seen This Man?," hosted by "The View's" Sunny Hostin.

Siler wondered if a psychological profile could help fill in some of the many gaps in his probe. He reached out to the U.S. Marshals Service chief psychologist Dr. Michael Bourke for answers.

Bourke is a former prison psychologist who runs the Behavioral Analysis Unit, a team of mental health experts, forensic scientists and criminologists who can help deputies dig into the mindsets of the fugitives they are seeking.

“We took a look at behavioral patterns and habits and other aspects of psychology that might inform how they direct their energy,” Bourke told ABC News. “In that mix is where you hope there's a breakthrough.”

The role of profiling in criminal investigations has seeped into popular culture through books and television shows like "Mindhunter" and "Criminal Minds." Experts said the potential for a deep psychological analysis to help uncover helpful ideas for finding Eubanks should not be underestimated.

“It can be a tremendous benefit to investigators,” said Bradley Garrett, a former FBI profiler and hostage negotiator who consults for ABC News. “It can help you to pull out behaviors that would give you indicators of what he might be connected to today.”

Bourke’s team looked at two main aspects of the Eubanks case. They looked for clues about his personality that might give Siler new directions for his search. And they provided guidance for how Siler could approach interviews with potential witnesses who may know something about Eubanks’ whereabouts but be reluctant to talk.

One important takeaway of the review, Bourke said, was his belief that Eubanks remains dangerous, calculating and at times impulsive, even as a man in his late 70s.

“What you see in him is an absence of caring and the ability to flip a switch and have his conscience disappear,” Bourke said. “He is absolutely capable of committing serious acts of harm.”

Even though much of the material in Eubanks' file dates back decades, Bourke said it is “extremely hard” for a grown adult to alter the way he interacts with others.

This aspect of Bourke’s analysis mirrored comments from the man whose mother harbored Eubanks in the early years after his escape in the 1970s. Darrell Banks, a cousin of Eubanks, was a teenager at the time. But he shared the belief that Eubanks would struggle to avoid some kind of physical conflict.

“With his personality and his physical stature, he had to end up getting in some kind of trouble with somebody, somewhere,” Banks told ABC News. “He can't control that temper that he had indefinitely without losing it once or twice at the wrong time, OK? Guaranteed, something happened, somewhere, at some point in time.”

Bourke said he believes the Marshals should prioritize finding ways to use DNA from Eubanks’ relatives to help track him down.

“I would say there is a probability that his DNA was taken from some sort of violent act or sexual act and is now sitting in a box [of evidence] somewhere,” Bourke said. “That’s a distinct possibility.”

Bourke also encouraged investigators to continue to seek help from friends and relatives of Eubanks – many of whom have been stubborn in their refusals to assist the Marshals.

The Marshal Service recently took the unusual step of doubling the reward money for information leading to Eubanks’ capture to $50,000, the most the service has offered for a 15 Most Wanted fugitive.

“I don’t know his family members,” Bourke said. “But I would almost bet that there is someone out there in his family that recognizes that doing the right thing for the family of Mary Ellen would add a little bit of justice back into the world.”

Siler said he thinks the consultation will benefit the investigation. Their input “opened up several other possibilities to target Eubanks and his associates,” he said.

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