Cadaver dogs helped sniff out a key lead this week in the case of four missing young men in Pennsylvania.
The working dogs led authorities to the remains of 19-year-old Dean Finocchiaro — the first of four missing Bucks County, Pa., men uncovered in a quadruple homicide investigation — buried on a 90-acre Solebury Township farm.
“I don’t understand the science behind it, but those dogs could smell these poor boys 12-and-a-half feet below the ground,” District Attorney Matthew Weintraub said.
That’s fairly deep for a burial, according to Mary Cablk, a detection expert and associate research professor at Nevada’s Desert Research Institute.
“Certainly when (a suspect has) access to equipment, they can dig down deep,” she told the Daily News. “Twelve and a half is pretty deep. That’s quite deep to cover up a homicide.”
And the science behind the corpse-sniffing pooches’ work, it turns out, is simple enough.
“The dogs are trained just like any other detection dog,” Cablk said. “You teach them: ‘This is what I’m looking for. When you smell it, go to it and communicate to me that you found it.’”
In this case, handlers train the dogs — most often German shepherds, labradors and golden retrievers — on the scent of death.
“Scent is made up of cells and what are called volatile fatty acids,” veteran cadaver dog trainer Marcia Koenig told The News. “Basically what you’re looking for is air exchange for it to come up through the soil.”
“And with four people in one area, there’s much more scent to come up,” she added of the Bucks County homicide investigation.
The canines’ ability to detect the rising scent hinges on the kind of soil, how tightly it’s packed, and how long the remains have been there, Koenig said.
A dog could have difficulty, for example, finding remains just six inches deep in tightly compacted clay, she said. Meanwhile, roots from vegetation can help provide a way for the scent to come out.
Many handlers train the dogs on placenta, blood or soil from where a person has decomposed, said Koenig, who has worked with search dogs since 1972.
“You reward them for indicating on the scent of decomposition,” she told The News. “The more the dogs work, and the more the dogs practice, the better they get at being able to get faint smells.”
It’s also important to only reward the dog for going to a human scent, not an animal scent, she added.
“If they go to the dead animal, we don’t get mad or anything,” Koenig said. “We just say, ‘No, that’s not going to get you a reward. Leave it and get back to work.’”
Though cadaver dogs tend to be accurate, Cablk said, “no detection dog is going to be perfect any more than any human is going to be perfect.”
“If they’re in the right area, and they’re well trained and they have good handlers, they’re likely to find it,” Koenig added.
In the case of the missing Pennsylvania men, the chances were likely high: Investigators had already narrowed the search perimeter to property owned by the parents of Cosmo DiNardo, who would ultimately confess Thursday to participating in the four murders.
“There was a high probability that they would find them, and obviously they did,” Koenig said. “It’s a good find, sad as it is.”