Forensic Pathology Device Sniffs Out Dead Air
August 13, 2008
“The Body Farm,” as the University of Tennessee Forensic Anthropology Facility has been known since inspiring Patricia Cromwell’s novel, was opened in 1971 by Dr. William Bass, who recognized the need for research into human decomposition after police repeatedly asked for his help analyzing bodies in criminal cases. What began as a small patch of land where one body was allowed to decompose in the open air for the sake of science has developed into a 3-acre complex that contains remains of around 40 individuals at any given time. Now, the Knoxville facility has been recruited by Orange County detectives for help in their continuing investigation into the disappearance of toddler Caylee Anthony.
After cadaver dogs responded to an odor emitting from the white Pontiac found abandoned by the child’s mother, Orlando investigators tapped The Body Farm for assistance in testing air samples from the trunk of the car. Using a sort of “artificial nose” which pulls air through a tube into a spectrometer chamber, the scientists will be looking for the presence of certain chemical compounds that are released only by a decomposing body. “After we die and the bacteria proliferate in our body and start breaking down our muscles and our fat and organs, vapors, gases, are formed with beautiful names like cadaverine (ph) and putrescine (ph) that are a particular structure that are easily picked up in the toxicology lab if they’re collected from the area, the air that the body was in,” says forensic pathologist Dr. Michael Baden. “If there was a dead body in the trunk of the car and they collected the air sample, they should be able to find those chemicals.”
Researchers at UT Knoxville could not say how long the air testing process will take, but results will be turned over to Orange County detectives once complete.
Would the results of the sniffer test in the Caylee/Casey Anthony case be admissable evidence in FL?
Have sniffer test results been accepted as true forensic evidence in any cases?
If so, in what states has sniffer tests been allowed?
Thank you
Pat Nelson
What an excellent question, Pat!
It does appear that the “sniffer test” will be admissible. “Gas chromatography” is not a new science, this particular test is merely a new application of it. Gas chromatography is one of four technologies used in breathalyzer tests, which are, of course admissible in court (see here) and is considered one of the two most reliable (albeit most expensive) of the four (see here).
Other applications for the technology are constantly being developed and are admissible in court, according to this excellent piece on forensic toxicology, which states, in part: “Scientists and researchers continue to improve and discover new means of separating, analyzing, and identifying chemical substances. Techniques are becoming more specialized, and technologies are being combined to create ever more sensitive and sophisticated tests. Two increasingly important approaches to chemical detection and identification are gas chromatography, a method of separating substances, and mass spectrometry, a method of measuring the mass of molecules. These techniques allow investigators to identify with reasonable certainty—admissible in a court of law—minute amounts of toxic substances found in the bodies of victims or in trace evidence collected at crime scenes.”
As to the particular case of Caylee Anthony, the Orlando Sentinel states that “air samples from her car were sent to the University of Tenn. Body Farm and those results confirmed the investigator’s preliminary conclusions” (that the trunk had contained a decomposing body) and WESH, Orlando states that “a prosecutor said that these odor results are admissible in court as forensic evidence, but he cautioned that they are not nearly as strong as DNA evidence,” so it remains to be seen how much weight a jury will assign to the test.
As much as I hate to quote from Nancy Grace’s show due to her complete disregard for the presumption of innocence of the Duke lacrosse team, this CNN transcript does contain some passages very relevant to your question. Asked if the test is considered reliable, forensic pathologist Dr. Michael Arnall, said, “It`s a new technology. The scientists at the University of Tennessee have published the results in scientific journals. And they`ve collected the air over decomposing bodies and they`ve characterized the compounds that one finds in that air. They`ve taken that air and they`ve put it through a relatively well established technology. That`s gas chromatography. But the new technology that they`ve brought to bear is they`ve characterized the specific compounds that are found next to a decomposing dead human body.” Asked specifically about the admissibility of the test, attorney Doug Burns said, “I think it`s going to boil down to the use of experts. In other words, Jane, they`ll prepare an expert report, they`ll give it to the other side. The other side will have an opportunity to have their own expert look at it and analyze it. It`s hard to say definitively. It`ll be up to the judge. I mean, if it`s a brand-new technology, maybe not. But I think it probably would be admissible.”
Finally, although your question was specifically asking about the admissibility of the “artificial nose,” this article from Forensic Magazine contains some fascinating information, including a chromatogram of armpit samples showing the uniqueness of scent and the admissibility of scent-evidence obtained via sniffing-dogs: “U.S. courts have diverse views about the admissibility of scent lineup evidence. In Winston v. State (Tex. App. 2002), for example, an appellate court noted that 37 states and the District of Columbia admit scent trailing evidence to prove the identity of the accused. As a relatively new use of the canine’s olfactory skill, the scent lineup will require scientific proof of reliability before identification evidence can withstand judicial scrutiny in all U.S. courts. Until then, the scent lineup remains a valuable tool for law enforcement during an investigation.”
I hope this has been helpful, Pat and, again, thank you so much for the thought-provoking question!