Opinion ID: 2975688
Heading Depth: 2
Heading Rank: 2

Heading: Causation Without Expert Testimony

Text: Kolesar’s next argument is that even if the district court correctly excluded expert testimony as to what caused Kolesar’s injuries, summary judgment was not proper. Under Wisconsin law, “[e]xpert testimony is required to prove causation if the matter does not fall within the realm of ordinary experience and lay comprehension.” Menick v. City of Menasha, 547 N.W.2d 778, 782 1 Dr. Chen even provided two definitions of RADS, one that excludes persons suffering from prior serious pulmonary conditions (the medically accepted definition) and one that can include patients with pulmonary conditions (the definition she gave after learning that Kolesar has asthma). Kolesar, 412 F. Supp. 2d at 697. -7- No. 06-1416 Kolesar v. United Agri Prods (Wis. Ct. App. 1996); see also Weiss v. United Fire & Cas. Co., 541 N.W.2d 753, 758 (Wis. 1995) (stating that “[t]he lack of expert testimony in cases which are so complex or technical that a jury would be speculating without the assistance of expert testimony constitutes an insufficiency of proof”). Kolesar classifies his case as involving “a simple negligence claim” and emphasizes that a lay jury would be able to understand causation “based on [his] undisputed exposure to metam sodium, the known effects of such exposure, and his treatment and symptoms after he was exposed to metam sodium.” Conversely, UAP asserts that this case involves an extraordinary and non-lay matter of causation because the metam sodium to which Kolesar was exposed was in liquid, not gaseous, form. Understanding the effect of the exposure would therefore require intricate knowledge of, among other things, the rate at which liquid metam sodium vaporizes into its more dangerous gaseous form. Kolesar objects to UAP’s argument, contending that elsewhere in its brief UAP admitted that the spilled metam sodium was dangerous without the need for expert testimony to establish as much. In its contributory negligence discussion, UAP essentially argues that because metam sodium is a known hazardous chemical, Kolesar should have known better than to act as he did. However, whether metam sodium is dangerous is not the issue requiring expert testimony in this case. Expert testimony is necessary to explain how Kolesar’s exposure to an admittedly corrosive, although nonvolatile, liquid metam sodium resulted in a significant exposure to an inhalable gas or vapor such that a juror could conclude Kolesar’s post-incident pulmonary symptoms were caused by the spill, rather than by his preexisting asthma. Without proof of causation, Kolesar cannot succeed on his -8- No. 06-1416 Kolesar v. United Agri Prods negligence claim. See Menick, 547 N.W.2d at 783. Therefore, the district court correctly granted summary judgment. C. Contributory Negligence and Wisconsin Public Policy Kolesar’s final argument is that the district court usurped the jury’s role in fault allocation when it stated that Kolesar is more liable than Defendants as a matter of law and that Wisconsin public policy supports barring Kolesar’s recovery. We need not reach this argument because regardless of whether the district court erred on this point, summary judgment was still proper. AFFIRMED. -9-