properly excluded). As Smith’s tests illustrates, a lay juror seeking to infer belt use from blood dispersal would not “know what to look for” and lacks the “right instruments.” Pries cannot aid plaintiff.
The relevant case law squarely supports the trial court’s grant of summary judgment. In Whitted v. General Motors Corp., 58 F.3d 1200 (7th Cir. 1995), for example, the plaintiff alleged that a defective seat belt failed to restrain him. Opposing defendants’ summary judgment motion, he argued that the mere “circumstances of the accident,” including a low-speed collision, could allow a juror to infer that the seat belt was defective. Id. at 1207. Noting that the “seat belt appeared to be in good working condition prior to the collision [and] that the seat belt had never demonstrated problems before,” the Court reasoned that plaintiff had not “nullif[ied] enough of the probable explanations” to warrant use of circumstantial evidence. Id. at 1208. The “circum- stances of the accident” were consistent with a “seat belt [that] acted properly.” Id. at 1207-09. Accordingly, the Court held that the circumstantial inference urged by plaintiff was “simply not enough to create a reasonable inference.” Id. at 1208. The same is true here. Summary judgment was correctly entered in defendants’ favor.