From The Ergoweb® Learning Center

Roxarsone-tainted Chicken Litter: A Red Flag for Forensic Ergonomists

A noted human factors expert and psychology professor, Arthur D. Fisk, Ph.D., PHFP, was disqualified as an expert witness in April in one of a string of lawsuits brought in Arkansas against the poultry industry. It’s an unremarkable suit that is attracting little media interest, but it promises to become a cautionary case study for forensic ergonomists.

The case centers on a growth-enhancer used in chicken feed called Roxarsone. Lawsuits claim Roxarsone, 3-nitro-4-hydroxypher ylarsonic acid, breaks down into arsenic in chicken litter. According to the allegations the litter, spread as fertilizer in the Prairie Grove area of Arkansas, has caused adverse health effects that include cancer. Representatives of the companies, which include Alpharma, Alpharma Animal Health, Cal-Maine Farms, Cargill, George’s, Peterson, Simmons and Tyson Foods — refute the claim.

Michael and Mary Green, whose son, Michael, suffered from leukemia as a child, are the lead plaintiffs in one of suits, and theirs will be the first to go to trial.

Dr. Fisk, known to many people by his middle name, Dan, is a psychology professor at the Georgia Institute of Technology. He is also a past president of the Human Factors and Ergonomics Society. Some 130 scientific publications and 125 scientific conference presentations on experimental psychology and human factors attest to his expertise.

As reported in the Northwest Arkansas Times on April 4, Clayton Davis, arguing for the plaintiffs, said Dr. Fisk’s expertise covers the decision-making process and the principles involved in designing hazards out of products. “The jury needs to understand that this man brings to the table that expertise and he can talk about it and explain it,” Davis said. He also said Dr. Fisk can talk about the alternative if a hazard cannot be designed out – which is to provide effective warnings – and about how people moderate behavior based on warnings.

Defense attorney Rob Adams countered that Fisk received all of his information about the case from the plaintiffs’ attorneys and reading materials. He said that anyone, such as a juror, could read the same information and come to the same conclusions. He also said Dr. Fisk admitted when deposed that he had no expertise on Roxarsone, arsenic or chicken litter.

The defense team filed motions to exclude Dr. Fisk’s testimony about the allegedly unreasonably dangerous nature of Roxarsone, the availability of alternative designs for chicken feed to design out the hazard and warning systems that could or should have been placed on Roxarsone.

Though Dr. Fisk’s background makes him ideally qualified to testify about decision-making and warnings issues, the reason he was called in by the plaintiffs, Washington County Circuit Judge Kim Smith granted the defendant’s motion to prohibit the testimony. The judge stated that Dr. Fisk is not qualified to testify on warnings about or alternatives to Roxarsone.

The defense attorney’s successful disqualification motions invoked the Daubert Standard, a legal precedent set by the United States Supreme Court about the admissibility of expert witnesses’ testimony during legal proceedings. It is raised before or during trial to exclude the presentation of unqualified evidence to the jury. In their Daubert v. Merrell Dow Pharmaceuticals ruling in 1993, the Supreme Court ordered federal trial judges to become the “gatekeepers” of scientific evidence and to evaluate expert witnesses to determine whether their testimony is both relevant and reliable.

Reacting to the disqualification, Y.Ian Noy, Ph.D., CPE, told The Ergonomics Report(tm) that forensic professionals are very aware of the Daubert standard. “I think the case … screams for better awareness of what forensic experts can bring to light in a case such as Roxarsone.” Dr. Noy served as an expert witnesses for many years and is now vice president and director of the Research Institute for Safety at the Liberty Mutual Research Institute. He is past president of the International Ergonomics Association (IEA), and his many publications include a recent book, “Handbook of Human Factors in Litigation.”


Kenneth Laughery, Ph.D. CPE, takes issue with the judge’s ruling. A long-time expert witness as well as a professor of psychology at Rice University, he believes the Daubert motion shouldn’t have succeeded. “As I understand it, the Daubert issue focuses on whether or not there is a scientific basis for the opinions, not the credentials of the witness,” he said in an interview with The Ergonomics Report(tm). Like Dr. Fisk, he is a past president of HFES, widely published in his field and a is popular speaker at professional conferences. He will deliver a keynote address on warnings, a focus of his research, and the IEA conference in The Netherlands in July.

The specifics of the judge’s ruling incensed Dr. Laughery. “I can’t imagine that Fisk was testifying about the dangerous nature of Roxarsone. That’s not his expertise. … I wouldn’t come in and say, ‘this stuff is toxic (and) it’s dangerous.’ Other experts, presumably, with that kind of expertise would make that (assessment.)” Referring to the barring of Dr. Fisk’s testimony on the availability of alternative designs of chicken feed, he said, “I’m not an expert on that either. Neither is Dan. I’m not a chicken feed, chemistry, toxicology expert. I would say to the extent there are economically and technically feasible alternative designs, then serious consideration ought to be given to implementing those. You shouldn’t have to rely on warnings if you can eliminate the hazard. But that’s not my expertise, and that’s not Fisk’s. It may be that that got confused in this case.”


Asked if the defense team was capitalizing on some apparent confusion about the intent of the Daubert motion, the Rice professor was scornful. “To the extent he was arguing that Fisk should be barred on the basis that he is not knowledgeable about the dangerous aspects of Roxarsone, (that) he is not knowledgeable or expert about the availability of alternative designs, that’s nonsense. That’s not Fisk’s, or mine or an ergonomist’s expertise. That’s toxicology. That’s chemistry. That’s (for) fertilizer experts.” Dr. Laughery said he didn’t know if defense attorney Adams knew better, but the argument isn’t relevant.

He also dismissed the judge’s ruling that Dr. Fisk did not have the scientific knowledge to say whether Roxarone is a dangerous product. “So what! That’s true. He’s not there for that.”

The judge stated that Dr. Fisk’s testimony about warnings for dangerous products would be a matter of common sense, a finding rebutted by Dr. Laughery. “That’s not true,” he said. “There is a huge amount of research that’s been done on warnings and that’s the expertise that Dan or I or other people in this field would bring to bear here. It’s not commonsense, any more than the chemistry and toxicology of the product is commonsense. If it’s commonsense, why aren’t warnings better?”

Professor Laughery found no merit in defense attorney Adams’ argument that Fisk admitted in his deposition he had never designed a warning for a consumer product. “Well, that’s true, and neither have I,” he said. “If you pick that argument apart you could say, ‘well, is somebody who has designed five bad warnings that have gone on consumer products okay as an expert?’ The issue is what scientific knowledge is there out there as to how warnings and warning systems should be designed to be effective. And that’s the Daubert question. Is there a basis for these opinions in the scientific literature? Not whether somebody has designed one or two warnings.”

“I can’t tell you …how many times I’ve read the testimony of a fact witness – that is, the employee of a corporate entity who has been responsible for designing the warnings on a product who had never read or had a clue about any research, guidelines and so forth as to principles of warnings and what kind of things influence their effectiveness. Now is that person an expert, and they have designed 20 bad warnings? So that doesn’t do it.”

For all that the Roxarsone case is raising ergonomists’ eyebrows because of the way the defense succeeded in eliminating what may have been a damaging expert witness, the Daubert motion is not an unusual strategy for lawyers on both sides of any case. Dr. Laughery has encountered it periodically in his 26 years testifying at trials, particularly when aspects of the case hang on the adequacy of warnings.

He worked on the litigation on which “Erin Brokovich,” the movie, is based. The true story centers on a single mother who takes Pacific Gas and Electric Company to court in 1993 over toxic pollution to the water supply. The case led to a record-breaking payout of $333 million – the largest settlement ever paid in a direct-action lawsuit in US history. He was also called to testify in the high-profile Ford Firestone litigation of 2002 and the 2004 Ephedra dietary supplement lawsuits. In many of these cases Daubert motions are made and rejected, he explained. “In recent years, it has become more of a kind of routine thing that defendants particularly will do to knock out plaintiff’s experts.”
More hearings are set to decide which designated expert witnesses will be allowed to testify, but there is no information yet on whether any of these will be ergonomists.

Classes and workshops for aspiring forensic ergonomists cover skills such as preparing for depositions and cross examination, how to deal with trick questions from opposing counsel and how to prepare opinions. As a cautionary saga the Roxarsone case and Dr. Fisk’s disqualification on a Daubert motion will be valuable additions to the curricula.

Sources: Northwest Arkansas Times; Dr. Y. Ian Noy; Dr. Kenneth Laughery

This article originally appeared in The Ergonomics Report™ on 2006-06-06.