Reported / Citable
Background
Richard Allen DuFour, Jr. worked for nearly three years on Deepwater Horizon oil-spill cleanup operations in Pascagoula, Mississippi, performing shoreline cleanup and boom decontamination. He alleged that inhalation and contact exposure to crude oil and chemical dispersants chronically worsened his preexisting asthma.
DuFour sued BP through the Medical Settlement Agreement’s Back-End Litigation Option. To establish causation, he offered Dr. Michael Freeman, who relied principally on studies of respiratory outcomes among spill-response workers, and treating physician Dr. Shawn French. The district court declined to hold a live Daubert hearing, excluded both experts’ causation opinions, and granted BP summary judgment.
The Court’s Holding
The Fifth Circuit affirmed. The majority held that general maritime law requires expert evidence of causation for toxic-exposure injuries that are not readily observable or may have multiple causes. It concluded that established maritime decisions—or, alternatively, a permissible uniform maritime rule developed by federal courts—support applying the familiar general- and specific-causation framework to claims like DuFour’s.
The court found no abuse of discretion in deciding the Daubert motions without a live hearing because the district court had extensive reports, declarations, depositions, briefing, and familiarity with the litigation. It also upheld exclusion of Dr. Freeman’s opinions because the cited studies did not reliably bridge the gap between chemical exposure and worsening preexisting asthma. In particular, the principal study excluded people with preexisting asthma and examined the risk of developing asthma, not aggravation of existing asthma.
The court likewise upheld exclusion of Dr. French’s causation testimony because the record did not establish his qualifications to assess the effects of the substances at issue, and he did not identify a reliable methodology connecting DuFour’s exposure to worsening asthma. With no admissible causation expert, DuFour could not prove an essential element of his claim, so summary judgment for BP was proper. Judge Oldham dissented, arguing that the governing substantive law remained unclear and that the district court applied Daubert too restrictively to DuFour’s evidence.
Key Takeaways
- Under Fifth Circuit maritime law, toxic-exposure injuries involving complex or competing causes generally require admissible expert evidence of both general and specific causation.
- A district court may resolve Daubert challenges on the written record without a live hearing when that record provides an adequate basis for evaluating reliability.
- A study addressing new-onset asthma did not reliably support an opinion that spill-related exposure worsened a plaintiff’s preexisting asthma.
- Once DuFour’s causation experts were excluded, Rule 56 permitted summary judgment because he had no evidence capable of proving legal causation.
Why It Matters
The decision reinforces the demanding expert-proof requirements facing Deepwater Horizon BELO plaintiffs with latent or medically complex conditions. Evidence that exposure can cause a disease in previously unaffected people may not establish that the same exposure aggravated a claimant’s preexisting form of that disease.
The opinion also confirms that federal courts may perform Daubert gatekeeping at summary judgment and enter judgment when exclusion of expert evidence leaves a plaintiff unable to prove causation. The dissent highlights an unresolved disagreement over how substantive choice-of-law rules should shape that reliability inquiry.