362 F. Supp. 3d 588
E.D. Wis.2019Background
- Three consolidated federal cases where plaintiffs allege childhood ingestion of paint containing white lead carbonate (WLC) caused neurocognitive and behavioral injuries. Plaintiffs sue five paint-related defendants.
- The court resolves multiple Daubert motions challenging the admissibility of plaintiffs' and defendants' expert witnesses on causation, exposure pathways, damages, and historical/public-health issues.
- Governing standards: Fed. R. Evid. 702 and Daubert gatekeeping; Wisconsin substantive causation standard (negligence and strict products liability under Thomas ex rel. Gramling). Experts may use differential etiology but need only reliably consider (not necessarily exclude) reasonable alternative causes.
- The parties dispute qualifications and methodologies of numerous experts (neuropsychologists, toxicologists, industrial hygienists, historians, vocational analysts, educators, radiologists).
- The court admits many experts on the basis that methodological flaws largely go to weight, not admissibility, but excludes or limits testimony where methods are unreliable, speculative, ipse dixit, or unduly prejudicial.
Issues
| Issue | Plaintiff's Argument | Defendant's Argument | Held |
|---|---|---|---|
| Proper Daubert gatekeeping standard | Experts meet Rule 702 if qualified and method reliable | Court must exclude unreliable or irrelevant expert opinions | Court applies Daubert, admits most experts whose methods are plausible, excludes those with unreliable or speculative methods |
| Adequacy of differential etiology (e.g., Trope) | Trope considered alternatives sufficiently | Defendants say she failed to rule out obvious alternatives | Admitted: expert need not rule out every alternative; must adequately consider/handle obvious alternatives |
| Use of epidemiological studies for individual causation (Besunder) | Epidemiology + records suffice to infer individual IQ effect | Defendants: population studies cannot prove individual causation | Admitted: applying epidemiology to individual medical records is an accepted method; challenges go to weight |
| Defense experts challenging causation without excluding lead (Karofsky, Banner, Bell, Tibbits, Joseph) | Plaintiffs: experts must consider/exclude lead as obvious cause | Defendants: may offer plausible alternative causes; need not always rule out lead | Admitted: defense experts may point to alternative causes; admissible if methodology for proposing alternatives is reliable |
| Expert opinions beyond expertise or speculative sweeping claims (Jacobs, Benedek, Banner) | Plaintiffs/defendants seek to limit scope | Parties challenge overbroad toxicology/population claims | Court excludes opinions outside expert's specialty or that are unsupported and sweeping (e.g., Benedek's generational claims, Banner's "no harm in 60s/70s") but admits qualified, fit general testimony (e.g., Jacobs on exposure mechanisms) |
| Unreliable methods, prejudicial or ipse dixit testimony (Schretlen, Webster) | Plaintiffs move to exclude defense experts for speculative or biased methods | Defendants argue qualifications/experience suffice | Excluded: Schretlen (unreliable IQ-estimation, unpeer-reviewed forensic data, prejudicial racialized content); Webster excluded as irrelevant/unqualified for historical opinion on paint uses |
Key Cases Cited
- Daubert v. Merrell Dow Pharms., Inc., 509 U.S. 579 (Daubert gatekeeping for expert testimony)
- Schultz v. Akzo Nobel Paints, LLC, 721 F.3d 426 (7th Cir. guidance on differential etiology and substantial-factor causation)
- Myers v. Illinois Cent. R.R. Co., 629 F.3d 639 (7th Cir. on differential diagnosis: rule in/out causes case-by-case)
- Kannankeril v. Terminix Intern., Inc., 128 F.3d 802 (3d Cir. on defendant challenging plaintiff's differential diagnosis)
- Gayton v. McCoy, 593 F.3d 610 (7th Cir. on expert need not list every possible cause)
- Thomas ex rel. Gramling v. Mallett, 285 Wis.2d 236 (Wis. 2005) (governing Wisconsin negligence and strict liability causation framework)