LEWISTON – Disregard the pauses between killings to work in a local restaurant. Ignore the smile. Put aside the second, third and fourth slayings.

Understanding Christian C. Nielsen – accused in the Labor Day weekend slayings of four people in Newry and Upton – all goes back to the first killing, says a nationally known expert on serial killers.

“I don’t believe he ever intended to kill four people,” said Casey Jordan, a criminologist and lawyer who teaches at Western Connecticut State University.

Of all the notorious killers she has interviewed – “Gainesville Ripper” Danny Rolling, Kendall Francois and Gianni Versace’s killer Andrew Cunanan – none planned any further than the first death, she said.

Maybe the other killings in the Maine case were to get rid of witnesses, Jordan said. Or maybe he’d begun to like killing.

“What happens different in serial killers is the ‘whatever’ factor,” she said.

Once they’ve killed someone and assured for themselves a life in prison if caught, serial killers can become more dangerous and erratic, she said

Perhaps Nielsen went there.

“We can only guess because so little information has been released yet,” said Jordan, who was interviewed by telephone from her Connecticut home.

She also warned that authorities may never learn what drove Nielsen, who, police say, has confessed to the crimes, to shoot and dismember people.

“Sometimes it’s part of a fantasy life only they understand,” she said.

State police arrested Nielsen on Sept. 4 after receiving a report of a dead body at the Black Bear Inn in Newry. When they arrived, they found the remains of innkeeper Julie Bullard, 65; her daughter, Selby Bullard, 30; and Selby Bullard’s friend, Cynthia Beatson, 43. The three women had been shot and dismembered. Police later found the remains of James Whitehurst, 50. His body had been burned in nearby Upton.

According to a police affidavit filed with the courts, Whitehurst was the first victim, killed on Friday, Sept. 1.

“It’s a very, very important case,” said Jordan, who is disappointed that more national attention has not been paid to it.

“It’s terrible because it affected ordinary people, people who could be you or I,” she said. “These victims are not Natalie Holloway, Elizabeth Smart or JonBenet. And there’s nothing better (that) TV likes than a manhunt.”

Jordan knows. She has appeared on TV as an analyst for CNN, “America’s Most Wanted,” Court TV and the NBC Nightly News.

The Newry slayings commanded Jordan’s interest because she has just completed a book about killers titled “Hybrid Killers: A Sign of the Times.”

When compared to the profile killers of the 1970s, ’80s and early ’90s, “This guy doesn’t fit,” Jordan said.

It’s her contention that while the number of murders has declined in recent years, the murderers have become more complex.

Serial killers are craftier than ever. They are learning to be more efficient than before, using knowledge from a variety of places, including movies and TV.

“They watch ‘CSI,’ too,” she said.

Their problems also seem more complex.

That might easily be seen in the relationship between Whitehurst and Nielsen, if there was a relationship, Jordan said.

“I can think of 100 reasons why the two might have argued,” she said.

The dismemberment of the victims might also suggest that he had problems with control, she said.

For people who work with meat, such as hunters or cooks, dismemberment of the victims is not as rare as it is for others, she said.

And for someone who kills, such an activity might not seem so horrific.

Not that a normal person could do it. Something has to snap.

“It’s not so much a snap as an implosion that takes place,” Jordan said.

Everything that made this human being a person is reduced somehow, she said. Often, they don’t remember what they did or they recall their actions as if they were done by someone else.

After the first slaying, Nielsen probably experienced near-paralyzing paranoia, Jordan said. Perhaps fear of being discovered is what led him to return to work that Sunday night, possibly after killing both Whitehurst and the elder Bullard.

Kendall Francois, who confessed to killing eight women in upstate New York in the late 1990s, told Jordan of his fear as he left one of his killings to return to work as a school security guard.

And the grin Nielsen wore as he first appeared in court?

“It disturbed me, too,” she said, seeing echoes of “Son of Sam” killer David Berkowitz. “I can’t make too much of that.

“Perhaps it was a defense mechanism,” she said. “Maybe he was nervous. I don’t think it was meant to offend.”