Decision Making by a Jury
Although many countries rely on the decisions of judges in civil and criminal trials, the jury is the foundation of the legal system in many other nations. The notion of a trial by one’s peers is based on the assumption that average individuals can make informed and fair decisions when they work together in groups. But given all the problems facing groups, social psychologists and others frequently wonder whether juries are really the best way to make these important decisions and whether the particular composition of a jury influences the likely outcome of its deliberation (Lieberman, 2011).
As small working groups, juries have the potential to produce either good or poor decisions, depending on many of the factors that we have discussed in this chapter (Bornstein & Greene, 2011; Hastie, 1993; Winter & Robicheaux, 2011). And again, the ability of the jury to make a good decision is based on both person characteristics and group process. In terms of person variables, there is at least some evidence that the jury member characteristics do matter. For one, individuals who have already served on juries are more likely to be seen as experts, are more likely to be chosen as jury foreperson, and give more input during the deliberation (Stasser, Kerr, & Bray, 1982). It has also been found that status matters—jury members with higher-status occupations and education, males rather than females, and those who talk first are more likely be chosen as the foreperson, and these individuals also contribute more to the jury discussion (Stasser et al., 1982). And as in other small groups, a minority of the group members generally dominate the jury discussion (Hastie, Penrod, & Pennington, 1983), And there is frequently a tendency toward social loafing in the group (Najdowski, 2010). As a result, relevant information or opinions are likely to remain unshared because some individuals never or rarely participate in the discussion.
Perhaps the strongest evidence for the importance of member characteristics in the decision-making process concerns the selection of death-qualified juries in trials in which a potential sentence includes the death penalty. In order to be selected for such a jury, the potential members must indicate that they would, in principle, be willing to recommend the death penalty as a punishment. In some countries, potential jurors who indicate being opposed to the death penalty cannot serve on these juries. However, this selection process creates a potential bias because the individuals who say that they would not under any condition vote for the death penalty are also more likely to be rigid and punitive and thus more likely to find defendants guilty, a situation that increases the chances of a conviction for defendants (Ellsworth, 1993).
Although there are at least some member characteristics that have an influence upon jury decision making, group process, as in other working groups, plays a more important role in the outcome of jury decisions than do member characteristics. Like any group, juries develop their own individual norms, and these norms can have a profound impact on how they reach their decisions. Analysis of group process within juries shows that different juries take very different approaches to reaching a verdict. Some spend a lot of time in initial planning, whereas others immediately jump right into the deliberation. And some juries base their discussion around a review and reorganization of the evidence, waiting to take a vote until it has all been considered, whereas other juries first determine which decision is preferred in the group by taking a poll and then (if the first vote does not lead to a final verdict) organize their discussion around these opinions. These two approaches are used about equally often but may in some cases lead to different decisions (Hastie, 2008).
Perhaps most important, conformity pressures have a strong impact on jury decision making. As you can see in Figure 10.12, when there are a greater number of jury members who hold the majority position, it becomes more and more certain that their opinion will prevail during the discussion. This is not to say that minorities cannot ever be persuasive, but it is very difficult for them. The strong influence of the majority is probably due to both informational conformity (i.e., that there are more arguments supporting the favored position) and normative conformity (people are less likely to want to be seen as disagreeing with the majority opinion).
This figure shows the decisions of six-member mock juries that made “majority rules” decisions. When the majority of the six initially favored voting guilty, the jury almost always voted guilty, and when the majority of the six initially favored voting innocent, the jury almost always voted innocence. The juries were frequently hung (could not make a decision) when the initial split was three to three. Data are from Stasser, Kerr, and Bray (1982).
Research has also found that juries that are evenly split (three to three or six to six) tend to show a leniency bias by voting toward acquittal more often than they vote toward guilt, all other factors being equal (MacCoun & Kerr, 1988). This is in part because juries are usually instructed to assume innocence unless there is sufficient evidence to confirm guilt—they must apply a burden of proof of guilt “beyond a reasonable doubt.” The leniency bias in juries does not always occur, although it is more likely to occur when the potential penalty is more severe (Devine et al., 2004; Kerr, 1978).
Given what you now know about the potential difficulties that groups face in making good decisions, you might be worried that the verdicts rendered by juries may not be particularly effective, accurate, or fair. However, despite these concerns, the evidence suggests that juries may not do as badly as we would expect. The deliberation process seems to cancel out many individual juror biases, and the importance of the decision leads the jury members to carefully consider the evidence itself.
- Under certain situations, groups can show significant process gains in regards to decision making, compared with individuals. However, there are a number of social forces that can hinder effective group decision making, which can sometimes lead groups to show process losses.
- Some group process losses are the result of groupthink—when a group, as result of a flawed group process and strong conformity pressures, makes a poor judgment.
- Process losses may result from the tendency for groups to discuss information that all members have access to while ignoring equally important information that is available to only a few of the members.
- Brainstorming is a technique designed to foster creativity in a group. Although brainstorming often leads to group process losses, alternative approaches, including the use of group support systems, may be more effective.
- Group decisions can also be influenced by group polarization—when the attitudes held by the individual group members become more extreme than they were before the group began discussing the topic.
- Understanding group processes can help us better understand the factors that lead juries to make better or worse decisions.
Exercises and Critical Thinking
- Consider a time when a group that you belonged to experienced a process gain, and another time showed a process loss in terms of decision making. Which of the factors discussed in this section do you think help to explain these two different outcomes?
- Describe a current social or political issue where you have seen groupthink in action. What features of groupthink outlined in this section were particularly evident? When in your own life have you been in a group situation where groupthink was evident? What decision was reached and what was the outcome for you?
- When have you been in a group that has not shared information effectively? Why do you think that this happened and what were the consequences?
- Outline two situations, one when you were in a group that used brainstorming and you feel that it was helpful to the group decision-making process, and another when you think it was a hindrance. Why do you think the brainstorming had these opposite effects on the groups in the two situations?
- What examples of group polarization have you seen in the media recently? How well do the ideas of normative and informational conformity explain why polarization occurred in these situations? What other factors might also have been at work?
- If you or someone you knew had a choice to be tried by either a judge or a jury, taking into account the research in this section, which would you choose, and why?
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