Even those who make their livings plumbing the darkest recesses of human behavior say they are appalled and perplexed by the so-called Miami face-eater.
"I've seen a lot of things and I've never seen anything like this," said West Palm Beach psychologist Stephen Alexander, who has examined some of the Palm Beach County's most notorious killers.
"This is so rare, so odd, it's overwhelming," agreed Dr. Bruce Harry, a psychiatrist at the medical school at the University of Missouri-Columbia who lists his interests as "serial killers in health care" and "epidemiology of human violent behavior."
It will be several weeks before toxicology tests reveal what drugs, if any, prompted 31-year-old Rudy Eugene to devour a homeless man's face during an unprovoked attack Saturday afternoon on the MacArthur Causeway. When Eugene ignored orders to stop, police shot him dead.
While eager to learn what drove Eugene to violate one of the most abiding taboos of Western civilization, psychologists and psychiatrists said they suspect it was fueled by a smorgasbord of drugs that tipped the balance for a man who had long suffered deep psychological ills.
"This is very unusual behavior," Alexander said.
The cannibalism alone is one for the record books, he said. "It's extremely rare," he said. "It usually involves severe perversion or mental illness."
However, in Eugene's case, cannibalism wasn't the only oddity. That the assault occurred in a public place, in broad daylight and that Eugene was naked make it all the more gruesome and inexplicable, Alexander said.
Harry agreed. Even the most infamous cannibals, such as Jeffrey Dahmer, performed their despicable acts in private. Convicted in 1992, the Wisconsin man lured more than a dozen young men into his apartment where he killed and dismembered them, keeping some of their body parts as trophies and eating others.
Eugene, in contrast, attacked and ate the face of his victim, Ronald Poppo, along a busy highway with cars and bicycles racing past. Grasping for logic to explain the illogical, Harry suggested that perhaps Eugene thought he knew the homeless man.
"You usually associate the face with personal identification," he said. "My guess would be maybe the man resembled someone who he thought he knew or associated him with someone who had wronged him."
Both he and Alexander suspect illegal drugs were involved. Topping their lists are: methamphetamine, crack cocaine, speed and possibly a synthetic drug cocktail known as bath salts, the latest scourge for authorities.
Bay County Sheriff Frank McKeithen, who has led a campaign to eradicate bath salts from the state, said he hopes the medical examiner in Miami tests Eugene's body to determine if he had taken the concoction. Too often such tests aren't done, he said, which masks the havoc that the dangerous, all-too available and ever-changing chemical cocktails are wreaking statewide.
People, he said, do astonishing things while hyped up on bath salts, a powerful synthetic drug that acts on the brain like a stimulant. One man, he said, ripped the radar unit out of the back of a patrol car with his teeth. Another shot through the floor of his apartment, convinced monsters were attacking him from below. A woman chased her mother with a machete, convinced she had to lop off her head to be safe.
"They're fighting things that aren't there" he said. "They're hallucinating."
Teri Barbera, a spokeswoman for the Palm Beach County Sheriff's Office, said deputies here are familiar with bath salts although they can't quantify how widespread their use has become. Unlike with other illicit drugs, deputies don't have a test they can administer to determine if odd behavior is the result of bath salts, she said.
Dr. David Bohorquez, director of medicine at St. Mary's Medical Center's emergency room in West Palm Beach who also works at Mount Sinai Medical Center in Miami, said he hasn't seen one case involving bath salts.
Both Alexander and Harry said bath salts could explain Eugene's macabre behavior. But, they said, other drugs, combined with mental illness, could as well.
"It's just too bizarre to be explained by a single theory," Harry said.