Jury instructions are a crucial part of any criminal or civil trial because they present the law to be followed in the verdict. The content of these instructions can be an adversarial part of any case. Variations in the instructions represent variations in legal standards, which presumably result in differing legal decisions. The Supreme Court will soon hear a case regarding jury instructions on contributory negligence and damages that raises several psychological issues.
Competing jury instructions
In Norfolk Southern Railway Co. v. Sorrell (docket number 05-746, ruling below at 170 S.W.3d 35), the plaintiff employee sued the railroad under the Federal Employers Liability Act and won a jury verdict of $1.5 million. In a civil tort case, jurors are generally required to determine if the plaintiff was injured and if the defendant acted negligently, causing the plaintiff's injuries. The defendant railroad in this case claimed contributory negligence, alleging that the plaintiff was partially responsible for his injuries. The standard used for determining the negligence of the defendant required a finding by the jury that the defendant "contributed in whole or in part to the cause of [the plaintiff's] injury." The defendant requested that this same standard be used to determine the contributory negligence of the plaintiff. However, the trial court instructed the jury to find contributory negligence if the plaintiff committed negligent acts that "directly contributed to cause his injury," consistent with the contributory negligence instructions from the state in which the case was tried. If the plaintiff was found contributorily negligent, the jury was required to decrease the plaintiff's award by the percentage of negligence attributable to the plaintiff, but the jury was not required to specify the percentage of negligence they attributed to each party. The Court will determine if the standard for negligence for the railroad can differ from the standard for contributory negligence of the plaintiff. A related question raised in the appeal but not under review by the Court is whether courts may rely on instructions and a verdict form that render it impossible to determine post hoc how the jury apportioned fault between the plaintiff and defendant.
Psychological implications for the jury
Although the issue before the Court is competing legal standards, the underlying issues are the jury's understanding of instructions, jurors' abilities to determine damages, and the effect of varying instructions on jurors' decision-making. Distinctions large enough to warrant appeal were drawn between the two standards used by the trial court. However, it is unclear that jurors draw the same distinctions between these instructions. Jury decision-making in civil cases and on damage awards has been investigated. See Edith Greene and Brian Bornstein's book "Determining Damages: The Psychology of Jury Awards" (APA, 2002) for a review. Overall, this research indicates that jurors have difficulty determining damages, partially due to the complexity and ambiguity involved in the process. Research also demonstrates that jurors have difficulty understanding and appropriately applying jury instructions. Extending these general findings to the case before the Court, it is possible jurors will have difficulty interpreting both standards for contributory negligence. The standards are linguistically different, but jurors might not understand them nor perceive them as requiring different decision strategies.
Although there is no research directly comparing the competing standards in this case, prior research on contributory negligence can further inform the Court's decision. The question presented in this case implies that jurors may potentially reach vastly different decisions based on the amount of contributory negligence they find. Research indicates this may not occur. For example, research has found that jurors are not sensitive to differentially worthy plaintiffs in their decision-making generally and are specifically not sensitive to varying levels of contributory negligence. Therefore, damage awards may not differ between differentially negligent plaintiffs regardless of the instructions. Instead, evidence of any contributory negligence appears to decrease the overall damage award in addition to the subsequent decrease by the percentage of fault attributable to the plaintiff--a process termed "double discounting." All of this research highlights that jurors' tasks in civil cases are difficult regardless of the instructions that might be used.
This case raises many issues that psychological research could inform. The research on determining damages that already exists could assist lawyers and judges in making decisions about jury instructions. However, further research can and should be conducted to improve civil decision-making. Psychologists and the legal system would benefit from research on ways to clarify the process of determining damages for jurors and on improving the utility of instructions for them.
Judicial Notebook is a project of APA's Div. 9 (Society for the Psychological Study of Social Issues).