In Brown v. Husky Injection Molding Systems, Inc., 2010 WL 4638761 (D. Mass. Nov. 17, 2010), a worker injured his hand when he reached into an injection molding machine that was not equipped with the standard “front pulley guard” on its frame. He sued the machine manufacturer in the United States District Court for the District of Massachusetts, asserting failure to warn and negligent and/or defective manufacturing claims. Defendant argued there was no evidence the machine was missing its front pulley guard when delivered to plaintiff’s employer and indeed there was evidence the employer had rebuilt the machine in 2000, some twenty-five years after it was manufactured and delivered by defendant. After the parties stipulated to dismissal of the failure-to-warn claims, defendant moved for summary judgment on the manufacturing defect claims arguing plaintiff could not prove the defect was caused by the manufacturer rather than an intermediate handler such as plaintiff’s employer.

The court first observed that a manufacturing defect claim is different from a design defect claim in that a design defect plaintiff need only show the defect existed at the time the product left the manufacturer. In contrast, a manufacturing defect plaintiff must also put forth evidence the defect was not caused by an intermediary party. Here, plaintiff offered two forms of evidence: (i) testimony of a fellow employee that no safety guards were removed from any of the machines during his years as an employee; and (ii) photographs appearing to show the machine lacked the capability for installation of a front pulley guard. Defendant offered testimony from an investigator that a pulley guard could have been attached, and noted that the employee whose testimony was relied on by plaintiff had not been hired until the year after the machine was delivered by defendant.

Plaintiff argued that he was not required to eliminate all possibility that defendant’s conduct was not a cause, but rather only to introduce evidence from which a reasonable juror could conclude it was more probable than not that plaintiff’s injuries were caused by defendant’s conduct. While the court agreed this was the correct legal standard, here plaintiff had offered no evidence at all to account for the machine’s condition between the time it was delivered and the time the testifying employee was hired. Even more critically, there was no evidence as to the presence or absence of a front pulley guard before and after the employer’s rebuilding of the machine in 2000. Accordingly, the court granted summary judgment based on plaintiff’s inability to prove the alleged defect was caused by defendant.