## Facts

- Homeowners owned a John Deere LX 178 lawn tractor manufactured by Deere and stored it in an attached garage.
- On July 13, 2003, Roula Kallivrousis attempted to mow; the tractor ran roughly and she stopped and parked it in the garage.
- About three hours later, a fire began and destroyed the home; the garage was identified as the area where the fire originated, and the tractor was located there.
- The homeowners’ insurer, Metropolitan, paid the loss and sued Deere in subrogation under Connecticut product liability law.
- Metropolitan alleged a latent defect in the tractor’s electrical system existed when the tractor left Deere’s control and that the defect caused the fire.
- Metropolitan could not identify a specific failed component and relied on circumstantial proof and expert opinions under a “malfunction theory,” asserting other causes had been ruled out.
- The tractor had been owned for years and had been serviced by a third-party dealership before the fire.

## Issues

1. Under Connecticut product liability law, may a plaintiff use the malfunction theory to prove defect and causation without identifying a specific defect?
2. Was the circumstantial evidence sufficient to permit a reasonable inference (rather than speculation) that a manufacturing defect existed when the tractor left Deere’s control and that the defect probably caused the fire?
3. Did the trial court err in denying Deere’s motions for a directed verdict and to set aside the verdict?

## Decision

- The Connecticut Supreme Court reversed the judgment for Metropolitan and directed that judgment be rendered for Deere.
- The court recognized the malfunction theory as a permissible method of proving defect and causation through circumstantial evidence.
- The court held the proof in this case was insufficient as a matter of law to show that a defect existed when the tractor left Deere’s control and that such a defect was the probable cause of the fire.
- Because Deere was entitled to judgment on evidentiary sufficiency grounds, the court did not need to resolve the remaining evidentiary challenges to drivability evidence and expert testimony.

## Legal Principles

- A product defect and causation may be proved by circumstantial evidence under the malfunction theory when a malfunction is shown and abnormal use and reasonable secondary causes are meaningfully excluded.
- The malfunction theory does not remove the plaintiff’s burden to show that the defect existed at the time the product left the manufacturer’s control.
- Circumstantial evidence must support a reasonable inference that the alleged defect and causal chain are more probable than alternative explanations; a verdict may not rest on conjecture where competing causes are equally or more likely.
- On review of a directed verdict or motion to set aside a verdict, the evidence is viewed most favorably to the verdict winner, but judgment must be entered for the movant if the proof is legally insufficient.

## Conclusion

The court permitted the malfunction theory in principle but found the insurer’s process-of-elimination evidence too attenuated, given the tractor’s age and intervening servicing and the lack of proof tying the fire to a manufacturer-caused defect existing at sale; it therefore reversed and ordered judgment for the manufacturer.


Metropolitan Prop. & Cas. Ins. Co. v. Deere & Co., 25 A.3d 571 (Conn. 2011)