The trial of three former Peanut Corporation of America (PCA) executives for allegedly causing a salmonella outbreak that killed 9 people and sickened over 700 more begins this week, and will feature key expert witness testimony in support of federal prosecutors. Brothers Stewart and Michael Parnell, along with former PCA quality control manager Mary Wilkerson, are charged with felonies for distributing contaminated peanuts, and experts from the Center for Disease Control (CDC) as well as private food laboratories look to aid the government’s case.
CDC Expert a Late Addition to PCA Trial
Key to the government’s prosecution of PCA’s executives is expert witness, Dr. Ian Williams, chief of the Outbreak Response and Prevention Branch at the CDC. Dr. Williams is the head of the CDC department that works with epidemiologists and other public health officials who investigate outbreaks of foodborne illnesses in the United States, and has a PhD in Infectious Disease Epidemiology from the Johns Hopkins School of Hygiene and Public Health.
In addition to his education and career qualifications, Dr. Williams has been chosen as a food contaminant expert witness due to his involvement in numerous multistate illness outbreaks since he began working with the CDC in 1994. Defense attorneys took exception to Dr. Williams because he was a late addition to the government’s witness list, but his qualifications and experience will contribute to the trial and he looks to be an important expert witness during the upcoming proceedings.
Additional Expert Witnesses to be reviewed during Trial
The government will call other food safety expert witnesses to demonstrate the PCA executives were aware of the peanut contamination, including Tracey Buchholz, the corporate director of quality for Deibel Laboratories Group. Deibel Labs is a food safety organization, and Mr. Buchholz has been called to testify about food quality in an effort to show that PCA either knew, or should have known, its peanuts presented a serious health risk – thus aiding prosecutors build the argument that PCA’s leadership team’s failure to prevent the salmonella outbreak is a criminal offense.
Buchholz and other potential expert witnesses will be reviewed for admissibility during the course of trial by presiding judge, W. Louis Sands. Judge Sands has cleared a total of 8 expert witnesses to offer testimony bolstering the government’s prosecution, and will allow for additional time during trial to hear arguments about other experts whose testimony may prove valuable. Expert witnesses must not only be qualified, but also be prepared to offer testimony that is both reliable and relevant to the issues at hand.
Defense Expert Witness Rejected
As blogged about here, the approval of the government’s expert witnesses comes shortly after Judge Sands rejected Mr. Parnell’s request for a neuropsychologist’s expert testimony explaining that the defendant’s ADHD prevented him from having the necessary mental capabilities to be aware of the extent of the peanut contamination. After a seven hour Daubert hearing regarding expert witness admissibility, Judge Sands determined that Dr. Joseph Conley’s unique expert testimony regarding the impact of ADHD lacked “a link with the allegations” in the PCA trial, and was therefore not relevant to the criminal proceedings.
With the PCA criminal trial set to begin, jurors will hear testimony from several expert witnesses that the government has prepared to explain the nature of contaminated food outbreaks, and connect the defendants’ behavior with the fatal peanut-born salmonella incident. Prosecutors hope to use the testimony of food safety experts to demonstrate that the three PCA executives knowingly distributed the unhealthy peanuts in violation of federal law, and are consequently guilty of causing the deadly salmonella outbreak.