Motion seeks to exclude testimony from professor
TULSA, Okla. (AP)--An expert scientist's testimony in a poultry litter pollution trial should be excluded because it's unreliable, confusing and unfairly prejudicial if presented to a jury, 13 Arkansas poultry companies claim in a new legal motion.
In a 431-page document filed May 8 in federal court, the companies want a judge to exclude the testimony of Valerie Harwood, a professor at the University of South Florida. Harwood is one of Oklahoma's expert witnesses in the state's 2005 lawsuit against the companies over allegedly polluting the 1 million-acre Illinois River watershed with bird waste.
A trial is expected to begin in September.
"As we explained in court last year, claims of scientific breakthroughs by experts working under the direction of lawyers in litigation should be viewed skeptically," said Gary Mickelson, a spokesman for Tyson Foods, one of the companies named in the lawsuit. "Science should be developed in laboratories and universities, not in courtrooms."
Charlie Price, a spokesman for the attorney general's office, said, May 11, that it wasn't surprising the companies were attempting to exclude the testimony.
"This is a normal, pretrial motion to which we will respond," he said. "We expect more of these motions to be filed in the weeks leading up to trial."
Harwood testified last year in a related case that she had identified a poultry litter-specific "biomarker," and reportedly traced a path that contamination from poultry waste travels from fields into the watershed.
Her science played a key role in Oklahoma's request for a federal injunction to prevent poultry companies from disposing of the waste in the watershed, a practice thousands of farmers have employed there for decades as a cheap fertilizer.
But last September, a federal judge ruled against an injunction, saying Oklahoma had not yet met its burden of proving that bacteria in the watershed are caused by poultry litter application, instead of sources like cattle manure and septic systems.
The judge also rejected Harwood's research and that of another expert witness, geochemist Roger Olsen, labeling their testimony as "not sufficiently reliable" because their work had not been peer reviewed or published.
That fact is noted in the new motion by the poultry companies: " ... defendants have confirmed the weaknesses in her methodology; and, in fact, Dr. Harwood's work has been severely criticized and rejected by a leading journal to which it was submitted for peer review," according to the court document.
In its rejection of Harwood's research, the Applied and Environmental Microbiology journal noted several concerns about the submitted work.
Among the most serious was "the potential for application of the method to other geographic regions, as other studies have shown that these biomarkers lose specificity when tests are conducted using samples from a broader geographic field."
Companies named in Oklahoma's lawsuit include Tyson, Tyson Poultry Inc., Tyson Chicken Inc., Cobb-Vantress Inc., Cal-Maine Foods Inc., Cargill Inc., Cargill Turkey Production L.L.C., George's Inc., George's Farms Inc., Peterson Farms Inc., Simmons Foods Inc., Cal-Maine Farms Inc. and Willow Brook Foods Inc.