Structured Risk Assessment and Legal Decision-Making

Abstract

The assessment of future dangerous behavior plays a central role in a variety of legal decisions. Instruments specifically designed to assess the risk of future dangerous behavior have proliferated and received myriad scholarly attention in the recent decades. By contrast, little is known empirically about the effect that such assessments have on legal decisions. This chapter reviews the fledging literature that has examined the impact of structured risk assessment on legal decisions. As a general matter, the existing studies suggest that structured risk assessment has a limited impact on legal decisions. For example, one field study found that actual jurors’ decisions were entirely insensitive to structured risk assessments, and a laboratory experiment found that mock jurors were responsive to a risk assessment but only when it supported their preferred verdict. Several possible explanations for why fact finders are insensitive (or selectively sensitive) to structured risk estimates are described. The prospect of using Decision Theory to mechanically make legal decisions in conjunction with structured risk assessment is then considered. Such an approach has the benefit of making all assumptions transparent and ensuring consistency in decisions. A numeric example is provided and discussed.