Grace Burke ran a stop sign and crashed into a car driven by Glen Jahn (plaintiff). Jahn’s car was manufactured by Hyundai Motor America (Hyundai) (defendant). The airbags in Jahn’s car did not deploy. Jahn suffered serious injuries in the accident. Jahn settled out of court with Burke, releasing her from all claims. Jahn then brought a products-liability suit against Hyundai in the United States District Court for the Southern District of Iowa. Jahn claimed that the airbags were defective and that their failure to deploy enhanced his injuries above and beyond those he would have sustained absent the defect. Hyundai argued that Burke’s negligence was the proximate cause of Jahn’s injury and that Burke’s fault could be compared with Hyundai’s own. The district court certified to the Supreme Court of Iowa the questions of (1) the applicable standard in an enhanced-injury case and (2) whether the comparative fault doctrine applies in the context of an enhanced-injury case.