The person capable of being the serial killer in the Gilgo Beach murders could be someone who goes through daily life unnoticed and may even seem "charming" to potential victims, said a former FBI profiler.
"The general public tends to think we need to be looking for a monster that oozes green slime and acts crazy, but that is just not the case," said Mary Ellen O'Toole, a former FBI special agent for 28 years who worked in the agency's Behavioral Analysis Unit. "They look as normal as you and me."
Such a killer would simply see his victims as prey, she said, and would be adept at hiding psychopathic traits, she said.
But the discovery of a second disposal site and more remains at Tobay Beach, that expert said, also leaves open the possibility that more than one murderer has found a convenient disposal site by the dunes of Long Island's South Shore.
"In a case as extensive as this, you would keep up parallel avenues of investigation," O'Toole said. "Detectives would already be keeping an open mind to at least the possibility that they are looking for more than one offender."
There have been cases where more than one perpetrator was at work -- such as the killings of more than a dozen women attributed to Derrick Todd Lee, known as "The Baton Rouge Serial Killer," and Sean Vincent Gillis, from the mid-1990s to the earlier part of this decade in Louisiana.
Sgt. Donald Stone, with the Baton Rouge Police Department, said both men were dumping bodies "in the same parish," overwhelming law enforcement agencies. Both men are behind bars, but it wasn't easy. "It was a rare occurrence," Stone said. "We had all our resources on it, and then anybody else we could use" in the investigation.
While evidence is examined, investigators here can consider who would zero in on young prostitutes selling sex on Craigslist, O'Toole said.
Serial murderers who are also sexual killers are usually men who "are very glib and charming" and can appear harmless.
They may even be men who get married and have children and "the trappings of living in society," she said.
Typical traits, experts say, include charm, a grandiose sense of self-worth and lack of remorse. They're also pathological liars and thrill-seekers who tend to be cunning and manipulative.
"One of the most profound characteristics and traits is that they have no empathy for other people," O'Toole said.
Based on the ways the bodies have been disposed of, out of reach and difficult to find even for police with trained dogs, experts agree the killer or killers do not want to be caught.
Vernon Geberth, a homicide and forensic consultant and former lieutenant commander with the NYPD, believes such a killer may be on the lookout for a new, undisturbed dumping site.
"He is definitely monitoring the case, reading the newspapers, following the news reports, but that won't stop him from killing," Geberth said. "He is a prolific serial killer who is highly organized."