Juror Deliberation

An Information Integration Analysis
  • Martin F. Kaplan
  • Cynthia Schersching
Part of the Perspectives in Law & Psychology book series (PILP, volume 2)


It is acknowledged fact that but a small percentage of criminal cases go to trial, and of these, the proportion heard by juries is not large (U.S. Bureau of the Census, 1976). Despite the relatively minor role played by juries in our justice system, however, interest in jury functioning remains particularly strong. This may be so for a number of reasons. First, the jury is the prime repository of societal mores (aside, of course, from the legislature) and it infuses social values directly into the justice system (Tocqueville, 1956). This, in fact, is one of the purposes for the creation of juries (Wigmore, 1929; see also Kaplan & Schersching, 1980). Second, the jury is composed of laymen relatively ignorant of the law; this situation provides an opportunity for observing the public’s response to the laws which govern it. Third, the jury processes divergent sets of information from varied sources to reach a single judgment with moral overtones. This is done first on an individual level, and then in a group context following discussion of the information. The psychological processes involved in information processing and in group interaction render the jury highly attractive for the study of social psychological processes, both intra- and interpersonally. This chapter will explore how jurors process the information they receive in the course of the trial, and most particularly, the effects of juror deliberation on the individual juror’s judgment.


Normative Influence Judgment Equation Informational Influence Information Integration Theory Judgment Dimension 


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Copyright information

© Plenum Press, New York 1981

Authors and Affiliations

  • Martin F. Kaplan
    • 1
  • Cynthia Schersching
    • 1
  1. 1.Department of PsychologyNorthern Illinois UniversityDe KalbUSA

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