Opinion ID: 1302539
Heading Depth: 3
Heading Rank: 3

Heading: Remaining Evidentiary Challenges.

Text: Plaintiffs' remaining claims are all challenges to various evidentiary rulings. To help facilitate the bellwether process, we briefly address each, although none has merit.
The district court did not err in prohibiting Plaintiffs' epidemiologist expert, Dr. Ruttenber, from testifying that scientific extrapolation supports a finding that radiation below 40 rads could cause hypothyroidism or autoimmune thyroiditis. Plaintiffs assert that the district court's rulings impermissibly required epidemiological studies to be a prerequisite to causation testimony. See In re Hanford, 292 F.3d 1124; Kennedy v. Collagen Corp., 161 F.3d 1226, 1229-30 (9th Cir.1998). The court's ruling, however, did not go that far. The court only precluded Dr. Ruttenber from, first, speculating that such extrapolation would likely produce results showing causation below 40 rads, and, second, stating that current epidemiological data do not contradict or prevent such a finding. Because the data Dr. Ruttenber used to make these two conclusions were not reliable, see Daubert v. Merrell Dow Pharms., 509 U.S. 579, 589, 113 S.Ct. 2786, 125 L.Ed.2d 469 (1993), the district court did not abuse its discretion in excluding Dr. Ruttenber's opinion.
The district court also did not err in permitting Defendants to cross-examine Plaintiffs' experts on alternative causes of thyroid disease. Plaintiffs' chosen methodology for proving causation was differential diagnosis, which is a process by which an expert compiles a comprehensive list of potential causes and then engages in a process of elimination to reach the most likely cause. See Clausen v. M/V NEW CARISSA, 339 F.3d 1049, 1057-58 (9th Cir.2003). Plaintiffs' experts enumerated possible causes of Plaintiffs' diseases, such as genetic predisposition, pregnancy, and stress, and then eliminated them, leaving radioiodine as the only probable cause. Having put these alternative causes at issue, Plaintiffs could not expect Defendants not to question the experts' rejection of them. Defendants were entitled to impeach the experts' methodology and their underlying conclusions.
Plaintiffs challenge the district court's ruling that Plaintiffs could not tell the jury that the federal government would indemnify Defendants for any liability imposed. Evidence of indemnification is generally inadmissible but may be used to show prejudice or bias of a witness. See, e.g., FED. R. EVID. 411. The only evidence to which a question of government bias might have arisen, however, was the Hanford Environment Dose Reconstruction Project (HEDR) and Plaintiffs stipulated to the accuracy of this document prior to trial. That stipulation is binding. U.S. Dep't of Labor v. Kerr-McGee Chem. Corp., 1985 F.2d 577, 5 OSHC (BNA) 2070 (9th Cir.1993); Am. Title Ins. Co. v. Lacelaw Corp., 861 F.2d 224, 226 (9th Cir.1988). There was thus no permissible ground on which Plaintiffs could introduce evidence of indemnification. The district court did not err in its application of Rule 411.
Plaintiffs' final contention on appeal is that the district court abused its discretion when it prohibited Plaintiffs' expert Dr. Hill from comparing radioiodine causation in animals to causation in humans. This ruling was not an abuse of discretion, because the information was not contained in Dr. Hill's pretrial expert report and Defendants were not allowed to question Dr. Hill regarding animal studies and thyroid disease at his deposition.