It seems Jose Baez saved the big guns for the end. Little by little, over the course of the past week and a half, Casey Anthony’s defense lawyers have tried to chip away at the prosecution’s battery of scientific evidence that suggests Anthony killed her two-year-old daughter, Caylee. On day 29, they took the biggest swing yet at discrediting the most compelling — but also the most controversial — forensic evidence.
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Prosecutors attempted to prove that Anthony stashed Caylee’s body in the trunk of her car based on decomposition odor analysis, the study of chemicals released when a body decomposes, that prosecutors say were found in Anthony’s trunk. Dr. Arpad Vass, a scientist at the Oak Ridge National Laboratory, testified early in the trial that the presence of certain chemicals proves that there was a decomposing body in the trunk of the car.
But some experts questioned the validity of Vass’s methods and whether they should have been admitted in court. “It’s what the state calls ‘state of the art.’ It’s what I call ‘not ready for prime time,'” Dr. Lawrence Kobilinsky, head of the Forensic Sciences Department at the John Jay College of Criminal Justice, told TIME.“It’s not junk science, but it never should be brought into a courtroom at this stage.”
The defense has already called one expert whose testimony refutes Vass’s theory, but today’s witness, Dr. Kenneth Furton, a chemistry professor who studies the chemistry of human decomposition, directly refuted Vass’s techniques. “It’s my expert opinion that there’s currently no instrumental method that has been scientifically validated to the level that it could be used to identify the presence or absence of human decomposition,” Furton said.
Furton’s testimony goes further than refuting damaging evidence; it calls into question whether Vass’s analysis should have been admitted in the first place. If Anthony is convicted of murdering her daughter, Baez will almost certainly argue that Furton’s testimony reflects the opinions of the greater scientific community. Florida, which adheres to the Frye standards of admitting scientific evidence, requires that the scientific community clearly support a technique before it can be used in a trial.
Today’s testimony came after an abrupt recess on Saturday where Casey was examined by three psychologists, who determined she is competent to continue with the trial. The defense is expected to wrap up its case this week.
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