Guided jury discretion in capital murder cases: The role of declarative and procedural knowledge

This article analyzes whether state-approved jury instructions adequately guide jury discretion in the penalty phase of first-degree murder trials. It examines Eighth Amendment jurisprudence regarding guided jury discretion, emphasizing the use of "empirical factors" to examine the quality of state-approved instructions. Psychological research and testimony on the topic of the comprehensibility of jury instructions are reviewed. Data from a recently completed simulation with 80 deliberating juries showed that current instructions do not adequately convey the concepts and processes essential to guiding penalty phase judgments. An additional simulation with 20 deliberating juries demonstrated that deliberation alone does not correct for jurors' errors in comprehension. The article concludes with recommendations for policy and future research.