Proportional Liability: Statistical Evidence and the Probability Paradox

Numerous writers have proposed modifying traditional tort rules to permit plaintiffs to recover from a defendant who contributed to the risk of causing the plaintiff's harm without proving that the defendant actually caused the harm. These proposals would determine recovery by multiplying the plaintiff's total damages by the percentage chance that the defendant caused the damages, thereby giving her a portion of her damages. Although these proposals for proportional liability take many forms, they may be divided into three major categories. The "proportional damage recovery" category would permit a plaintiff to recover a portion of her damages only after she has suffered the injury or acquired the disease.' Thus, if a defendant created a twenty percent probability of having caused the harm, an injured plaintiff would re- cover twenty percent of her damages.

If a defendant created a sixty percent probability of having caused the harm, the plaintiff would re- cover sixty percent of her damages.