Opinion ID: 2778508
Heading Depth: 2
Heading Rank: 2

Heading: Admission of Dr. Brown’s Expert Opinion

Text: Union Pacific argues that the district court abused its discretion in admitting Dr. Brown’s testimony “because his opinions are wholly unconnected to the facts of this case.” It contends that Dr. Brown “refused to consider pertinent facts” and instead “inspected and considered one piece of evidence—the axles themselves.” As mentioned above, Union Pacific did not move in limine to exclude Dr. Brown’s opinions. Accordingly, there is no district court order for us to review. Union Pacific instead has cited the objections it made at trial to Dr. Brown’s opinions that no corrosion pits remained on the DeWitt axle after it was reconditioned, that the -9- derailments were not caused by corrosion pits, and that the cause of the Martin Bay axle failure was fatigue initiation caused by fretting.4 Having reviewed the transcript pages cited in Union Pacific’s opening brief, we find no abuse of discretion in the district court’s rulings. Iwand and Dr. Brown reached opposite conclusions about whether corrosion pits remained on the axles after Progress Rail reconditioned them. In a sidebar conference, Union Pacific’s counsel argued that Dr. Brown’s opinion was unreliable because he examined the DeWitt and Martin Bay axles in August 2012 and did not know how the axles were stored during the years between the derailments and his inspection. After Dr. Brown explained that his opinion was based on his inspection of the axles, as well as the forensic evidence that was developed by Iwand, the district court overruled Union Pacific’s objection to the foundation of his opinion. Dr. Brown also explained that he found no corrosion pitting associated with the fracture initiation sites on the axles. He opined that without corrosion pitting present at the initiation sites, the derailments could not be attributed to the presence of corrosion pits that purportedly were not removed during the reconditioning process. Dr. Brown testified that he found fretting on the fracture initiation site of the Martin Bay axle, however. He opined that “the fretting introduced a stress concentration which allowed a fatigue crack to initiate and grow.” Union Pacific has not identified any gap in Dr. Brown’s methodology, and his testimony is clear: He could not trace 4 Iwand defined the term “fretting” as “a type of damage that occurs between two surfaces that are pressed together; in other words, they [a]re pushing together, but there [i]s still micromotion that takes place between the two pieces. That micromotion, at a microscopic level, allows the parts to weld together between the two pieces. And then as that motion continues, they break.” Dr. Brown explained that the fretting on the Martin Bay axle occurred when the “contact between the backing ring of the bearing and the fillet . . . generated a dent, a line in the fillet in that area; actually multiple lines.” -10- the cause of the fatigue cracks to corrosion pitting, but he was able to trace the cause of the fatigue crack in the Martin Bay axle to a specific defect—fretting. Accordingly, we conclude that Progress Rail laid an adequate foundation for Dr. Brown’s opinions and that the district court acted within its discretion when it overruled Union Pacific’s objections.5