Inquiry and deliberation in judicial systems : The problem of jury size

Summary, in English

We raise the question whether there is a rigorous argument favoring one jury system over another. We provide a Bayesian model of deliberating juries that allows for computer simulation for the purpose of studying the effect of jury size and required majority on the quality of jury decision making. We introduce the idea of jury value (J-value), a kind of epistemic value which takes into account the unique characteristics and asymmetries involved in jury voting. Our computer simulations indicate that requiring more than a > 50 % majority should be avoided. Moreover, while it is in principle always better to have a larger jury, given a > 50 % required majority, the value of having more than 12–15 jurors is likely to be negligible. Finally, we provide a formula for calculating the optimal jury size given the cost, economic or otherwise, of adding another juror.

• Author: Staffan Angere; Erik J Olsson; Emmanuel Genot
• Editor: Can Baskent
• Department/s: Theoretical Philosophy; Lund University Information Quality Research Group (LUIQ)
• Publishing year: 2016
• Language: English
• Pages: 35-56
• Publication/Series: Perspectives on Interrogative Models of Inquiry : Developments in Inquiry and Questions
• Full text: - 780 kB; Download statistics
• Links: http://dx.doi.org/10.1007/978-3-319-20762-9_3
• Document type: Book chapter
• Publisher: Springer
• Topic: Philosophy
• Status: Published
• Project: Collective Competence in Deliberative Groups: On the Epistemological Foundation of Democracy
• Research group: Lund University Information Quality Research Group (LUIQ)
• ISBN/ISSN/Other: ISBN: 978-3-319-20762-9; ISBN: 978-3-319-20761-2