ORLANDO, Fla. (AP) - A novel forensics technique introduced in Casey Anthony's murder trial this week has the promise to do what the noses of highly-trained cadaver dogs are able to do - sniff out decomposition and locate hidden bodies.
That technique had never before been used in a criminal case until the trial of the young Florida mother, who is charged with killing her 2-year-old daughter Caylee. It may end up being the most controversial piece of forensics evidence presented in the trial.
Anthony's defense attorneys tried to stop Oak Ridge National Laboratory senior researcher Arpad Vass from testifying for prosecutors, claiming his method was too experimental. The Orlando prosecutor's office has a history of using novel techniques in the courtroom - it was among the first to use DNA evidence in a criminal case.
"His opinions and theories range from the interesting to the bizarre," Anthony's attorneys said in court documents. But Circuit Judge Belvin Perry ruled that any decision about the reliability of Vass' methods should be left to jurors.
The 25-year-old Anthony is accused of killing Caylee in June 2008 and disposing of her body. She faces a possible death sentence if convicted.
Her defense attorney, Jose Baez, says the toddler drowned in the family's swimming pool and that after Casey panicked, her father helped cover up the death, which he denies. The girl's decomposed body was found by a meter reader in some woods near the parents' home in December 2008.
The car's smell has played a role in the case since the beginning.
Shortly after their daughter and granddaughter disappeared, Casey's parents, George and Cindy Anthony, got a notice from a tow lot that her car had been picked up and needed to be claimed or it would be salvaged. They picked up the car and it reeked of a foul odor. George Anthony, a former police officer, and the tow lot operator both said the car smelled like a dead body had been inside.
When the Anthonys tracked down Casey at a friend's house and she couldn't produce Caylee, Cindy Anthony called 911 and told the operator the car smelled like death. Baez says the odor came from a bag of garbage that had been left in the trunk in the hot Florida summer.
Investigators brought in Vass, who had gotten some attention in 2008 for his work using his odor detector to search for buried bodies at a California ranch where convicted murderer Charles Manson and his followers lived in the late 1960s. None were found.
In the Anthony case, Vass and a colleague used a syringe to extract an air sample from a can holding a carpet sample that had been pulled from the Pontiac Sunfire. They then injected the air into an instrument called a gas chromatography/mass spectrometric to identify the substances it contained.
The substances were then compared against a database of more than 400 chemical compounds Vass has identified from the decomposition of bodies at the University of Tennessee Anthropological Research Facility. Donated bodies at the facility, dubbed "The Body Farm," were buried in different depths of soil. Hoods were placed over the locations of the bodies to capture the chemical compounds as they were liberated from the decomposing bodies over four years.
Vass backed up prosecutors' theory, testifying Monday that he smelled an "overwhelmingly strong" odor of human decomposition in the air sample. He told jurors that his machine found high levels of chemical compounds observed when the body breaks down, such as chloroform, in the sample taken from Anthony's car.
Anthony's attorneys claim Vass' tests haven't been duplicated anywhere else and that the researcher has refused to share his database, claiming it is proprietary.
During cross-examination Monday, Baez suggested that Vass stood to make money off of his method if it is adopted by police departments.
"You sir, have a financial interest in your testimony here today, do you not sir?" Baez said Monday.
"Not in my opinion," Vass answered.
But two defense scientists say Vass' technique is too premature for use in criminal cases.
"To allow the presentation in court of the findings ... in this case would lend it an aura of scientific authority not justified by its novel nature," said Barry Logan, an expert in toxicology.
Florida International University analytical chemist Kenneth Furton said no scientifically valid method of identifying human remains based on chemical residue existed.
"Previously touted techniques for locating human remains have not been demonstrated to be reliable," Furton said in court documents. He added that Vass' methods "are still in the experimental stage."