Scott Johnson v. Mead Johnson & Company
754 F.3d 557
| 8th Cir. | 2014Background
- Infant H.T.P. (neonate) fed Mead Johnson powdered infant formula (PIF); later developed severe meningitis and brain damage; spinal fluid culture grew Cronobacter sakazakii (C. sak).
- CDC/FDA tested unopened and one opened cans collected from the home and found no contamination; household environment and the consumed can were not tested.
- Plaintiff (Scott Johnson, guardian ad litem) sued Mead for products liability, negligence, and failure to warn, alleging Enfamil PIF contaminated with C. sak caused the infection.
- Johnson proffered three experts (Drs. Jason, Farmer, Donnelly) who used differential etiology to "rule in" PIF and "rule out" alternative sources (e.g., home environment, tap water).
- District court excluded the experts under Rule 702 as unreliable (primarily because experts did not test the home and water specifically for C. sak) and granted summary judgment and costs to Mead.
- Eighth Circuit reversed: held the district court abused its discretion by excluding the experts; differential etiology was a reliable methodology and admissible, creating a jury question on causation.
Issues
| Issue | Plaintiff's Argument | Defendant's Argument | Held |
|---|---|---|---|
| Admissibility of expert causation testimony under Fed. R. Evid. 702/Daubert | Experts used accepted differential etiology to "rule in" PIF and sufficiently address alternatives; testimony is reliable and helpful | Experts failed to reliably "rule out" other sources (no home testing; water tests not specific), so methodology is unreliable | Reversed: experts' methodology was scientifically valid and should be admitted; exclusion was an abuse of discretion |
| Whether experts must rule out all possible alternative causes | Not required; experts need not eliminate every possible cause—shortcomings go to weight, not admissibility | Argued insufficiency in ruling out alternatives undermines admissibility | Court: experts are not required to rule out all causes; gaps affect weight for jury, not admissibility |
| Application of Glastetter precedent (limits on differential diagnosis) | Glastetter does not bar admission here because PIF as a source is established and experts relied on relevant literature and methods | Mead relied on Glastetter to show experts' major premises were unproven and methodology invalid | Court: Glastetter distinguishable; major premise (PIF can contain C. sak) is established; experts' methods admissible |
| Grant of summary judgment after expert exclusion | With experts excluded, plaintiff lacks specific-causation evidence and cannot survive summary judgment | Summary judgment appropriate because plaintiff cannot prove causation without experts | Reversed: because experts should have been admitted, summary judgment cannot stand; remanded for further proceedings |
Key Cases Cited
- Daubert v. Merrell Dow Pharm., 509 U.S. 579 (trial courts must assess scientific validity and relevance of expert testimony)
- Kumho Tire Co. v. Carmichael, 526 U.S. 137 (Daubert gatekeeping applies to all expert testimony)
- Glastetter v. Novartis Pharm. Corp., 252 F.3d 986 (8th Cir.) (differential diagnosis admissible but not when major premise unproven)
- Turner v. Iowa Fire Equip. Co., 229 F.3d 1202 (8th Cir.) (differential diagnosis is a tested, generally accepted methodology)
- Lauzon v. Senco Prods., 270 F.3d 681 (1st Cir.) (gaps in experts' information go to weight, not admissibility)
- In re Prempro Prods. Liab. Litig., 586 F.3d 547 (8th Cir.) (expert need not eliminate all possible causes; admissibility favors testing by adversarial process)
- Sappington v. Skyjack, Inc., 512 F.3d 440 (8th Cir.) (summary-judgment facts viewed in light most favorable to nonmoving party)