## Facts

- Civilian U.S. government employees at Concord Naval Weapons Station handled missile canisters and reported smelling fumes, becoming dizzy, and leaving the area.
- In the morning, three plaintiffs handled a single canister manufactured by Martin Marietta Corporation (MMC).
- In the afternoon, three plaintiffs handled six canisters: three manufactured by MMC and three by a different manufacturer not sued.
- A Navy investigation indicated likely exposure to toluene; it found low levels in two MMC canisters handled in the afternoon and suggested the canisters may have leaked.
- Plaintiffs alleged serious neurological, respiratory, and psychological injuries from toxic exposure and also sought damages for fear of developing cancer.
- Plaintiffs sued MMC and Martin Marietta Technical Services, Inc. (MMTS) for negligence and strict products liability.
- Defendants moved for summary judgment and/or summary adjudication.

## Issues

1. Whether MMC was entitled to summary judgment under the federal government contractor defense.
2. Whether plaintiffs produced sufficient evidence of causation for negligence and strict products liability, including where multiple manufacturers’ canisters were involved.
3. Whether plaintiffs could recover fear-of-cancer damages under California law without evidence linking their physical injuries to a medically verifiable cancer risk.
4. Whether the evidentiary record supported liability against MMTS.

## Decision

- The court denied summary judgment to MMC on the government contractor defense because the record did not establish, as a matter of law, a significant conflict between state tort duties and federal procurement obligations.
- The court denied summary judgment to MMC on causation for the morning plaintiffs because a reasonable factfinder could infer the single MMC canister caused their exposure and injuries.
- The court granted summary judgment to MMC on causation for the afternoon plaintiffs because the evidence showed only that MMC canisters might have caused their injuries, not that they actually did, given multiple potential sources and insufficient proof distinguishing among them.
- The court granted summary judgment to defendants on fear-of-cancer damages because plaintiffs lacked evidence of a verifiable causal nexus between their injuries and cancer risk.
- The court granted summary judgment in full for MMTS due to insufficient evidence tying it to actionable conduct causing plaintiffs’ injuries.

## Legal Principles

- A negligence plaintiff cannot satisfy causation by showing only that a defendant might have caused the harm; the evidence must permit a reasonable inference that the defendant’s conduct or product actually caused the injury.
- Where multiple potential causes exist, causation is not established by mere possibility without additional proof connecting the injury to the particular defendant; burden-shifting doctrines do not apply solely because causation is difficult to isolate.
- Fear-of-cancer damages under California law require evidence of a medically verifiable causal nexus between a present physical injury and an increased risk of cancer; subjective fear alone is insufficient.
- The government contractor defense requires proof that state tort duties significantly conflict with federal contract obligations; absent a record showing government direction sufficient to create that conflict, summary judgment is improper.

## Conclusion

The court allowed claims to proceed only where plaintiffs presented evidence supporting a reasonable inference that MMC’s product caused the exposure, rejected claims resting on “might have caused” theories in a multi-source setting, barred fear-of-cancer damages without a verifiable medical connection, and dismissed MMTS for lack of evidence of responsibility.


Barron v. Martin Marietta Corp., 868 F. Supp. 1203 (N.D. Cal. 1994)