PROTOTYPES IN THE COURTROOM - LAY REPRESENTATIONS OF LEGAL CONCEPTS

To select a verdict, jurors must integrate the evidence presented at trial with the law presented in the judge's instructions. Jurors are assumed to have no prior knowledge of the law or to set aside that knowledge after instruction. Several experiments (N = 489) tested these assumptions and revealed that (a) uninstructed Ss had built naive representations of crime categories that included legally incorrect information; (b) these representations contained category prototypes that influenced Ss' verdict choices; and (c) Ss' reliance on prototype information for verdict selection was resistant to change by instruction. Thus, Ss had prior knowledge of the law and did not set it aside after hearing the judge's instructions. This suggests that instructions must do more than create legal concepts where none exist; to be effective, instructions must revise jurors' existing concepts.