This guest post was written by David Booth Alden of Jones Day. We thank Dave for the contribution and remind you to credit (or blame) him, not us, for what follows:

Product liability plaintiffs generally prefer to try cases in which the evidence relates only to parties that are in court and from whom they can recover a judgment, preferably a big one. Product liability defendants generally prefer that large sums of their money not be awarded to plaintiffs and, thus, usually are happy to have responsibility allocated to anyone other than themselves. Where all potentially responsible parties – PRPs for short – are named as parties, both sides get their way. Juries generally are permitted to apportion fault between and among the plaintiff and all PRPs on a percentage basis.

But all PRPs often are not in court. And, for a variety of reasons, the jury may not be permitted to apportion fault to the absent PRPs. For example, the absent PRP may be immune from liability (e.g., employers), may have settled or gone bankrupt, or perhaps no longer exists. Or the plaintiff may have failed to name a PRP before a statute of limitations ran or elected not to name the PRP for strategic reasons.

When there are absent PRPs to whom the jury cannot allocate fault, plaintiffs and defendants want very different things. The plaintiff wants to preclude all reference to the absent PRPs because, notwithstanding their inability to apportion fault them, the jury may allocate some or all responsibility to the absent PRP, thereby absolving or reducing any judgment against the defendant. Because the absent PRP may, in reality, bear responsibility for the plaintiff’s injury, the defendant wants to explain that fact to the jury.

The defendant often may introduce at least some of this highly relevant evidence by invoking the “sole proximate cause” doctrine, which “advise[s] the jurors … that they do not have to place blame on a party to the suit if the evidence shows that … the conduct of some person not a party to the litigation caused” the injury. Dillard v. Texas Elec. Corp., 157 S.W.3d 429, 432 (Tex. 2005). When the defendant raises a “sole proximate cause” defense, evidence relating to absent PRPs’ culpability should be admissible.

But not in asbestos cases in Illinois, at least not until the Illinois Supreme Court’s recent decision in Nolan v. Weil-McLain, No. 103137, 2009 Ill. LEXIS 381 (Apr. 16, 2009). There, the plaintiff brought an action against Weil-McLain and eleven other defendants alleging that their products exposed her now-deceased husband, Clarence Nolan, to asbestos, which in turn caused his mesothelioma. Nolan had performed millwright work, plumbing, pipefitting and boiler installation and repair for 38 years beginning in 1952. Weil-McLain makes boilers and, before 1974, its boilers had some asbestos-containing parts. Nolan testified that he worked on Weil-McLain boilers 20-25 times during his 38-year career. Nolan had filed an earlier lawsuit in 1988 seeking recovery for his asbestosis and, in that action, did not name Weil-McLain.

By the time of trial, eleven defendants had settled, which left Weil-McLain as the only defendant. Weil-McLain sought to offer Nolan’s deposition testimony that he had been exposed to “numerous asbestos-containing products neither made nor supplied by” Weil-McLain, “including instances … when asbestos dust ‘rained down’ on him from insulation and he ‘certainly’ inhaled it.” Id. at *6-7. The plaintiff, relying on a trio of intermediate Illinois appellate court decisions, objected that the “other exposure” evidence was irrelevant, confusing, and prejudicial. The trial court excluded the “other exposure” evidence, but gave a “sole proximate cause” instruction. The jury returned a $2.368 million verdict for the plaintiff, which was reduced by $1.22 million due to the other defendants’ settlements.

The intermediate appellate court affirmed. It found that (a) under Thacker v. UNR Industries, Inc., 151 Ill. 2d 343, 603 N.E.2d 449 (1992), once a plaintiff passed a threshold showing of regular exposure to the defendant’s product over a substantial period of time, there was a presumption of proximate causation that shifted the burden of proof to the defendant; and (b) once the Thacker presumption applied, a trio of intermediate appellate court decisions required excluding evidence of exposure to other manufacturers’ asbestos products as irrelevant.

The Illinois Supreme Court reversed. Initially, it found that Thacker set forth the standard for evaluating whether a plaintiff had introduced enough evidence to submit the causation question to the jury, but “create[d] no presumption on the issue of causation” and did not shift the burden of proof. Id. at 27. Then, it found that the exclusionary rule prohibiting asbestos defendants from showing exposure to non-defendants’ asbestos-containing products “‘effectively removed from asbestos defendants any opportunity to point to the negligence of another as the sole proximate cause of plaintiff’s injury.’” Id. at *33 (citation omitted). According to the court, “a defendant ‘has the right not only to rebut evidence tending to show that defendant’s acts are negligent and the proximate cause of claimed injuries,’ but also ‘has the right to endeavor to establish by competent evidence that the conduct of a third person, or some other causative factor, is the sole proximate cause of plaintiff’s injuries.’” Id. at *38 (citation omitted).

This is a drug and device law blog and some readers may simply write this off as a mildly interesting correction of one of many problems that have afflicted asbestos cases. But the fundamental tension about how to treat absent PRPs arises in prescription drug product liability actions, too. For example, in Ackermann v. Wyeth Pharmaceuticals, 456 F. Supp. 2d 809 (E.D. Tex. 2006) (Bush, M.J.) [Disclosure: My firm, and blogging co-host Herrmann, and I represented Wyeth], the plaintiff alleged that Wyeth’s antidepressant caused her decedent’s suicide. For several days before his suicide, however, the decedent had not taken Wyeth’s antidepressant; instead, he had taken an antidepressant manufactured by another manufacturer that the plaintiff chose not to sue. The plaintiff moved in limine to exclude all evidence relating her decedent’s use of the absent manufacturer’s drug unless Wyeth named that manufacturer as a PRP under Tex. Civ. Prac. & Rem. Code § 33.004, which would have permitted her to assert otherwise time-barred claims against that manufacturer. Although not expressed in terms of “sole proximate cause,” the court denied the motion on that basis, finding that evidence relating to the other manufacturer’s antidepressant could be relevant in assessing whether the other drug – and not Wyeth’s antidepressant – caused the suicide. Id. at 811.

Sole proximate cause can also arises in the context of defendants arguing that the plaintiff’s own conduct was the cause of an injury and that there is no need to have a jury assess comparative fault. E.g., Labzda v. Purdue Pharma, L.P., 292 F. Supp. 2d 1346, (S.D. Fla. 2003) (Snow, M.J.) (recommending entry of summary judgment dismissing product liability claims relating to Oxycontin user’s overdose death because user’s conduct was sole proximate cause), adopted, 292 F. Supp. 2d 1346 (S.D. Fla. 2003). Similarly, it may be a basis for summary judgment when a learned intermediary failed to read the manufacturer’s warnings. Harris v. McNeil Pharm., No. 3:98cv105, 2000 U.S. Dist. LEXIS 22972 (D.N.D. Sept. 5, 2000).

Accordingly, correcting the law relating to sole proximate cause, even in a somewhat different context, is a positive development.