Scientific Standards in Asbestos Trials

Appellants appeal a denial of motion for judgment notwithstanding verdict, as the plaintiffs at trial did not and could not prove that defendant’s asbestos product was a “substantial factor” in causing mesothelioma in Mr. Norris (deceased) as required by Rutherford v. Owens-Illinois, Inc., (1997) 16 Cal. 4th 953, 982. Appellants assert that Mr. Norris’ disease related death was caused by exposure to asbestos used on the values in the ship that Mr. Norris served on during the 1950’s, but failed to bring sufficient evidence to prove substantial causal connection. (Evidence suggests that the United States Navy, the least cost risk mitigator, insurer, and information acquirer, knowingly exposed its personnel to harmful asbestos dust, and did not require them to wear masks when slinging the fibers into the air by sweeping the dust, and did not instead have their personnel mop the dust which would have minimized exposure and lessened their personnel’s risk of developing a foreseeable disease).

Issue Areas:

Sound Science

Question(s) Presented:

Was the evidence shown at trial sufficient to prove a substantial causal connection between Crane’s asbestos product and Mr. Norris’ disease?

ALF’s Amicus Brief:

Amici submit that Rutherford and well-reasoned authority from other jurisdictions suggest that a showing of some minimal exposure is insufficient to infer causation of an adverse health event when a threshold of exposure has been shown to be requisite to infer causation. A majority of jurisdictions have adopted the “frequency, regularity, and proximity” test adopted by the Fourth Circuit in Lohrmann v. Pittsburgh Corning Corp., (4th Cir. 1986) 782 F.2d 1156. In Lohrman the Fourth Circuit rejected the showing that the plaintiff had been exposed 10-15 times for a period of one to eight hours over a 39 year period as insufficient to infer the exposure was a substantial factor in causing plaintiff’s disease. This test prevents plaintiffs from offering theories asserting that any exposure, no matter how minimal, is a substantial causative factor, supported by testimony not based in scientific facts, standards, or learning.

Amici represent scientists who offer this Court methodological standards of causative factor determination that plaintiffs should be held to in assessing the level of relative exposure, which should require an assessment of the “dose” which could differentiate a poison from a cure, and the type of fiber which is partially determinative of the strength of the exposure over time. Because of the confounding factors present in the plaintiff’s expert testimony, and a lack of consideration that the type of asbestos exposure from Crane’s valve product has been shown to be far less intense than the type of asbestos this expert’s study equates it to, the conclusions asserted by the expert relating to causation are at best speculative and unsupported.




On March 11, 2008, the California Appeals Court issued an adverse opinion, in which it held Crane to the consumer expectation standard, although the Navy and not its personnel were the consumers.

Date Originally Posted: February 3, 2008

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