The Tenth Circuit recently affirmed the dismissal of a suit seeking to hold a gunmaker n liable for injuries a woman alleged she suffered when a rifle fired spontaneously.  Harris v. Remington Arms Co., LLC, 997 F.3d 1107 (10th Cir. 2021). The case turned on the admissibility of plaintiff’s expert evidence.

Roughly two years after buying the rifle, Ms. Harris took it to hunt. As she climbed to a tree stand, the rifle got tangled in mesh. Ms. Harris alleged that when she had tried to free the rifle from the mesh, the safety moved to the “off” position and the rifle fired into her hand without anyone pulling the trigger. Ordinarily, a rifle has two separate safeguards preventing an unintentional shot. The first is the safety mechanism. When the safety is on, the rifle can’t fire. The second is the trigger mechanism. Remington puts space between the mechanisms for the safety and trigger so that a user must pull the trigger to fire the rifle.

Plaintiff’s expert first opined that a bond had formed between the two separate mechanisms after the Harrises engaged the safety and stored the rifle in a cold room, causing a liquid bonding agent to solidify. But there was a logic issue here. Remington argued that if a bond had formed from the cold, the rifle would have improperly fired when Mr. Harris turned the safety off at least a year earlier in order to clean the rifle. There was nothing to suggest that the rifle had misfired before Ms. Harris went to hunt. And once the bond broke, the liquid bonding agent wouldn’t solidify again. Confronted with Remington’s argument, the expert changed his explanation, opining for the first time that the bond had formed when a lubricant (called “Molykote”) moved between the safety and trigger mechanisms and caused the liquid bonding agent to solidify.

This raises an important question.  Is expert discovery like a tennis match, with volley responding to volley?  Most courts say it is not. Here, the Harrises did not timely disclose Mr. Powell’s opinion testimony about the movement of Molykote. This opinion did not appear in Mr. Powell’s expert report or deposition testimony, and the Harrises did not disclose this opinion until more than two months after the deadline for expert reports. Id. at 1112.

In deciding whether the delay was harmless, the court considered four factors:

1. the prejudice or surprise to Remington if Mr. Powell could present his new opinion testimony about the movement of the Molykote,
2. the opportunity for Remington to cure the prejudice,
3. the potential for the new opinion testimony to disrupt the trial, and
4. the Harrises’ bad faith or willfulness.
See Jacobsen v. Deseret Book Co., 287 F.3d 936, 953 (10th Cir. 2002).

Here, the district court properly found that

The district court explained that:
• the introduction of the new Molykote opinion would have delayed the trial,
• the case had lingered longer than most of the cases on the court’s docket, and
• the Harrises could have learned earlier about the effect of the Molykote.

Lacking an expert opinion on these issues of defect and causation, summary judgment was granted. And the court of appeals affirmed.