I dissent.
As in the companion case, Buttram v. Owens-Corning FiberglasCorp. (1997) 16 Cal.4th 520 [66 Cal.Rptr.2d 438, 941 P.2d 71], the majority's holding will deprive numerous innocent plaintiffs suffering from so-called "latent" diseases caused by exposure to asbestos in the workplace of full *Page 986 compensation for injuries inflicted by tortfeasors. In my view, the burden-shifting instruction at issue is generally consistent with state law and was properly given in this matter. Although the point is not technically at issue here, I would also observe that use of the burden-shifting instruction should not require waiver of any punitive damages claim.
I. Charles Rutherford worked as a sheet metal worker at the Mare Island Naval Shipyard for 40 years. During 10 of those years, from 1940 to 1950, he worked on ships around asbestos insulators. He brought this action, against various manufacturers of asbestos, including Owens-Illinois, Inc. (hereafter Owens-Illinois), after he discovered that he had contracted lung cancer; after his death, the action was amended by his wife and daughter to allege wrongful death. Owens-Illinois manufactured the product "Kaylo," containing asbestos; Kaylo was one of the products used at Mare Island between 1940 and 1950.
In the first phase of a trifurcated trial, the jury found that Rutherford had cancer legally caused by his inhalation of asbestos fibers. By the second phase of trial, all defendants had settled except for Owens-Illinois. The burden-shifting instruction given to the jury in this phase, Solano County Complex Asbestos Litigation General Order No. 21.00, required plaintiffs to prove, by a preponderance of the evidence, the following: (a) the asbestos product manufactured or distributed by Owens-Illinois was defective; (b) Rutherford's injury was legally caused by his exposure to or contact with asbestos products; and (c) he was exposed to, or had contact with, an asbestos product manufactured by Owens-Illinois. The burden then shifted to Owens-Illinois to prove, by a preponderance of the evidence, that its product was not the legal cause of the injury. By electing the burden-shifting instruction, plaintiffs were deemed to waive any claim against Owens-Illinois for punitive damages.
The jury found for plaintiffs. Owens-Illinois does not dispute the jury's determination that its product was defective. Nor does it dispute the jury's finding that Rutherford's injury was legally caused by his exposure to asbestos or that its products were used at Rutherford's workplace. It contends that it should not have been required to carry the burden of proof that its product was not the legal cause of the injury.1
Unlike the majority, I conclude that the burden-shifting instruction was proper. Its rationale derives from the nature of asbestos-related injury. *Page 987 Plaintiffs suffering from the effects of industrial exposure to asbestos typically were exposed to the substance from many products. Here, for example, the plaintiffs sought to prove that asbestos-related cancer is caused by the cumulative effect of all such exposure. Thus, although any given exposure may not have been enough itself to cause injury, each exposure contributed to the inflammation process that eventually results in asbestos-related disease. The question is only the extent of harm caused by each such exposure.2
It appears that relatively light exposure to asbestos places a worker at risk for asbestos-related diseases. (See Borel v.Fibreboard Paper Products Corporation (5th Cir. 1973)493 F.2d 1076, 1083; Armstrong World Industries, Inc. v. Aetna Casualty Surety Co. (1996) 45 Cal.App.4th 1, 37-39 [52 Cal.Rptr.2d 690] .) Nonetheless, a defendant may contend that its contribution to the total asbestos exposure was so slight that it cannot be considered a substantial factor. As a practical matter, it is, moreover, difficult or impossible to determine which exposure or exposures actually caused the disease. Without a burden-shifting instruction, if each defendant argues that its product was only a small part of a plaintiff's total exposure, and that it therefore could not have been a substantial factor in causing his injury, there is a risk that a jury might find that no one manufacturer was responsible for the injury, even though all of the manufacturers together caused the harm. This is particularly true in light of the exceptionally long latency periods from initial exposure to the onset of asbestos-related disease and the nature of the typical industrial environment, involving multiple exposures to various asbestos products over a period of time.3 *Page 988
Without the burden-shifting instruction, it would appear that many innocent plaintiffs who were unknowingly exposed to products such as Kaylo in the workplace would face serious, even insurmountable, difficulties in establishing that exposure to a specific defendant's defective product was a substantial cause of injury. Indeed, although the majority assert that, "in general," no "insuperable barriers" prevent a plaintiff from meeting the burden of proof, even defendant concedes that in many cases the placement of the burden of proof will be dispositive. This is particularly true in light of the majority's requirement that plaintiffs must bear the formidable burden of establishing legal cause through factors including frequency of exposure, regularity of exposure, proximity of the asbestos product to plaintiffs, and other possible sources of plaintiffs' injury. With a burden-shifting instruction, the risk is avoided because each defendant bears the burden of proving that its own contribution to plaintiff's exposure was not a substantial factor in his resulting disease.4
The burden-shifting instruction also finds support in the holding in Pereira v. Dow Chemical Co. (1982) 129 Cal.App.3d 865 [181 Cal.Rptr. 364]. Pereira was an action to recover damages for personal injuries for a permanent kidney disorder sustained by an employee after a chemical spill at his place of employment. The plaintiff also claimed injury from the cumulative effect of his exposure to chemical products manufactured or distributed by the various defendants, which were used at his workplace for several years. He was unable, however, to prove which exposure or exposures caused his injury. The Court of Appeal held that the burden of proof on the issue should rest with the defendants. "Under the circumstances, it is not plaintiffs' duty to identify which of the vapors caused or contributed to the chronic renal failure but, rather, it is the duty of the defendants who supplied [his employer] with their products to prove the contrary." (Id. at p. 873.)
Owens-Illinois argues that the burden-shifting instruction was improper because plaintiffs in other jurisdictions have been able to prove, without *Page 989 such burden shifting, that a defendant's product was a substantial factor in causing asbestos-related disease. It is unclear, however, precisely what was the plaintiffs' burden of proof in those jurisdictions, e.g., whether the court imposed a more lenient standard of proof of exposure than the one adopted here. If the burden-shifting instruction were truly unnecessary, it seems unlikely that Owens-Illinois would so strenuously urge that we hold it invalid.
Under the circumstances of this case, I believe the burden-shifting instruction was proper. It bears repeating that plaintiffs' burden remained substantial: they were required to establish that the Owens-Illinois's product, Kaylo, was defective, that Rutherford was exposed to Kaylo, and that he sustained an asbestos-related injury. Only then did the burden of proof shift to Owens-Illinois to show that his exposure to its product was not a substantial factor, i.e., a legal cause of, the injury.
II. Although I conclude that the trial court properly gave the burden-shifting instruction in this matter, it erred in conditioning its use on plaintiffs' waiver of any claim for punitive damages. It appears that the trial court relied onMagallanes v. Superior Court (1985) 167 Cal.App.3d 878 [213 Cal.Rptr. 547]. Its reliance was misplaced.
Magallanes involved a suit against multiple defendants based on the market share theory of liability we crafted in Sindell v. Abbott Laboratories, supra, 26 Cal.3d 588. Sindell involved a situation in which the plaintiff was unable to identify which of numerous defendants manufactured the drug that actually caused her injury. We held that it was reasonable to "measure the likelihood that any of the defendants supplied the product which allegedly injured plaintiff by the percentage which the [drug] sold by each of them . . . bears to the entire production of the drug sold by all defendants for that purpose." (Id. at pp. 611-612.) The burden then would shift to the defendants to demonstrate that they could not have made the drug that injured the plaintiff. (Id. at p. 612.) Magallanes held that punitive damages are not available in such a case because they were intended to individualize punishment of wrongdoers and, in a Sindell-type action, there could be no finding of individual wrongdoing.
Magallanes is, of course, distinguishable from the present case. Plaintiffs did not base their action on a market share theory. They were required, under the burden-shifting instruction, to prove that they were exposed to asbestos *Page 990 manufactured by the specific defendant. Under the circumstances, I discern no valid reason why they should have been precluded from seeking punitive damages.
Appellant's petition for a rehearing was denied October 22, 1997, and the opinion was modified to read as printed above. Mosk, J., was of the opinion that the petition should be granted.