In Smith v. Illinois Central Railroad Co., the Fourth District of Illinois recently overturned a $1.4 million verdict against the Illinois Central Railroad. At trial, the Court had excluded evidence of the decedent's work at the UNARCO asbestos plant in Bloomington, Illinois on the ground that the defendant did not have an expert to testify that the exposure at UNARCO was the "sole proximate" cause of the decedent's disease, asbestosis. The Fourth District found that the trial court's ruling was erroneous and "particularly egregious."

This decision reaffirms the Illinois Supreme Court's reasoning in both Leonardi v. Loyola University of Chicago and Nolan v. Weil-McLain and should make it abundantly clear to asbestos trial judges that the "sole proximate cause" defense is not an affirmative defense for which defendants have any burden of proof, as plaintiffs routinely argue, but rather is merely a component of the plaintiff's burden of proving proximate cause.

In its decision, the Fourth District found that the Supreme Court's decisions in Leonardi and Nolan were quite clear that the plaintiff has the burden to prove that the defendant's product was the proximate cause of the disease and that the defendant was entitled to introduce evidence to challenge that argument. Having an expert to testify on "sole proximate cause" was not required to introduce the evidence and challenge plaintiff's claim of concurrent causation.

Per the court: "Based on our supreme court's opinions in Leonardi and Nolan, defendant in this case did not have to prove anything. We find plaintiff's argument defendant had no-proximate-cause defense because he had no expert witnesses disclosed on causation is simply incorrect as a matter of law. Defendant did not need to establish UNARCO was the sole proximate cause of plaintiff's condition. However, for plaintiff to prevail, he had to establish defendant was a proximate cause of his asbestosis. While defendant had no obligation to do so, it should have been allowed to present evidence of plaintiff's UNARCO work experience in an attempt to establish plaintiff's exposure at UNARCO was to blame for plaintiff's asbestosis should the jury find plaintiff had asbestosis. Because the trial court did not allow defendant to present this evidence, once the jury found plaintiff had asbestosis, it could only conclude the asbestosis was caused by plaintiff's exposure to asbestos while working for defendant." Id. at p. 36-7.

The ruling provides the opportunity for asbestos defendants to utilize Smith as continued support for the clear mandate that they do not need to prove by expert, or otherwise, that alternative exposures were the sole proximate cause, even in cases in which the diagnosis of an asbestos-related disease is contested. Instead, defendants may argue that the jury be allowed to see the entirety of a plaintiff's asbestos exposures – not just a particular defendant's alleged exposure.