The danger of asking jurors about danger: An investigation of mock jury sentencing in capital cases

Forty jurisdictions sanction capital punishment. However, public opinion polls of support for the death penalty have recently reached an all-time low. Capital sentencing systems in the United States have been undergoing recent criticism and scrutiny. Moratoriums are being considered or have been implemented in some states. Recent studies of the death penalty cast serious questions about whether the current frameworks are operating constitutionally. In particular, four areas of concern arise from this research: how jurors use and interpret aggravating and mitigating factors, how jurors\u27 difficulty comprehending death penalty jury instructions affects their decision making, how jurors\u27 attitudes affect their decision making, and how jurors\u27 judgment of the dangerousness of the offender in death penalty cases (an aggravating factor in at least 18 states) affects their sentencing decisions. Three mock capital sentencing trial experiments were conducted. Jury-eligible participants participated and were presented with guilt and penalty phase evidence. Study one varied 6 aggravators and mitigators, and 5 instructional improvement techniques, measuring how evidence, instruction, and attitudes toward the death penalty affect decision making. Study two varied 3 aggravators and mitigators, focusing on how these influence decisions about an offender\u27s dangerousness. Study three varied expert witness testimony on dangerousness (including the magnitude of risk, the format of the presentation of that risk, and the scope of the testimony), exploring the impact of this testimony and the potential for the conflation of the culpability decision with the dangerousness judgment. Across studies, attitudes accounted for more of the variance in death penalty sentencing than did any other factor including the evidentiary manipulations or instruction comprehension. Concern about an offender\u27s dangerousness was the second most influential factor on sentencing decisions. Finally, no support was found for the hypothesis that instruction comprehension mediates sentencing decisions. These findings raise serious concerns regarding whether or not the constitutional standards articulated by the Supreme Court are being achieved in the current capital sentencing frameworks in the United States