Key Takeaway

The defendant is liable for the aggravation of plaintiff’s existing injury or condition, regardless of whether the magnitude of the full injury/disability/secondary harm was foreseeable.


Benn v. Thomas

Benn v. Thomas

512 N.W.2d 537 (1994)

(Eggshell Plaintiff)


On February 15, 1989, on an icy road in Missouri, a semi-tractor and trailer rear-ended a van in which Loras J. Benn was a passenger. In the accident, Loras suffered a bruised chest and a fractured ankle. Six days later he died of a heart attack.

At trial, the estate's medical expert, Dr. James E. Davia, testified that Loras had a history of coronary disease and insulin-dependent diabetes. Loras had a heart attack in 1985 and was at risk of having another. Dr. Davia testified that he viewed "the accident that was in and the attendant problems that it caused in the body as the straw that broke the camel's back" and the cause of Loras's death. Other medical evidence indicated the accident did not cause his death.

Based on Dr. Davia's testimony, the estate requested an instruction to the jury based on the "eggshell plaintiff" rule, which requires the defendant to take his plaintiff as he finds him, even if that means that the defendant must compensate the plaintiff for harm an ordinary person would not have suffered.

The estate claims that the court erred in failing to include, in addition to its proximate cause instruction to the jury, a requested instruction on the eggshell plaintiff rule. Such an instruction would advise the jury that it could find that the accident aggravated Loras's heart condition and caused his fatal heart attack. 


Whether the trial court erred in refusing to instruct the jury on the "eggshell plaintiff" rule in view of the fact that plaintiff's decedent, who had a history of coronary disease, died of a heart attack six days after suffering a bruised chest and fractured ankle in a motor vehicle accident caused by defendant's negligence.


A tortfeasor whose act, superimposed upon a prior latent condition, results in an injury may be liable in damages for the full disability. This rule deems the injury, and not the dormant condition, the proximate cause of the plaintiff's harm. This precept is often referred to as the "eggshell plaintiff" rule, which has its roots in cases such as Dulieu v. White & Sons, where the court observed:

If a man is negligently run over or otherwise negligently injured in his body, it is no answer to the sufferer's claim for damages that he would have suffered less injury, or no injury at all if he had not had an unusually thin skull or an unusually weak heart.”

Although the eggshell plaintiff rule has been incorporated into the Damages section of the Iowa Uniform Civil Jury Instructions, we believe it is equally a rule of proximate cause.

The proximate cause instruction failed to adequately convey the existing law that the jury should have applied to this case. The eggshell plaintiff rule rejects the limit of foreseeability that courts ordinarily require in the determination of proximate cause. Once the plaintiff establishes that the defendant caused some injury to the plaintiff, the rule imposes liability for the full extent of those injuries, not merely those that were foreseeable to the defendant.

The instruction given by the court was appropriate as to the question of whether defendant caused Loras's initial personal injuries, namely, the fractured ankle and the bruised chest. This instruction alone, however, failed to adequately convey to the jury the eggshell plaintiff rule, which the jury reasonably could have applied to the cause of Loras's death.


To deprive the plaintiff estate of the requested instruction under this record would fail to convey to the jury a central principle of tort liability.

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