Psychology in the Courtroom: Juror Factors and Decision Making

Learning Outcomes and Overview of Juror Factors

• Primary Learning Objectives:     * Develop a comprehensive understanding of how specific juror characteristics may influence decision-making processes within the courtroom.     * Cultivate a critical awareness regarding the influence of these characteristics on real-world legal case outcomes.     * Critically evaluate the key academic debates and issues surrounding the potential impact of juror traits on the legal process.

• Categories of Juror Characteristics identified:     * Prior Experience     * Social factors     * Economic status (Socioeconomic Status - SES)     * Personality traits     * Gender     * Education level     * Emotional state     * Ethnicity and Race     * Age

Theoretical Models of Juror Decision-Making

• The Story Model (Pennington & Hastie, 1986, 1988):     * This is an explanation-based model of juror decision-making.     * Jurors utilize prior knowledge, existing schemas, and personal expectations to construct a narrative or "story" from the evidence presented.     * Defendant characteristics often shape how evidence is evaluated, which version of the story is perceived as most plausible, and the perceived credibility of parties involved.

• Dual Process Theory of Attitude Formation and Change (Eagly & Chaiken, 1993; Elaboration Likelihood Model, Petty & Cacioppo, 1986):     * Central Route: Characterized by systematic, effortful, and analytical processing of the information.     * Peripheral Route: Characterized by a reliance on short-cuts, heuristics, and superficial cues rather than the core message.

• General Predictability of Demographics:     * Academic consensus suggests that few juror demographic characteristics are strong or reliable predictors of verdict preferences (Bonazzoli, 1998; Saks, 1997).     * Evidence often reveals weak and inconsistent effects (Boyll, 1991; Fulero & Penrod, 1990; Hastie et al., 1983; Visher, 1987).     * Note: While individual demographics may be weak predictors, less research has focused on interacting juries, though some studies indicate jury-level effects do exist.

Juror Personality: Authoritarianism and Dogmatism

• Trait Definitions:     * Authoritarian Personality: Individuals who conform to societal norms, follow conventional morals, and are prone to stereotyping others. They exhibit an exaggerated respect for authority and adhere rigidly to traditional values.     * Dogmatic Personality: Individuals who are close-minded and prone to distrusting others. They are highly intolerant of ambiguity and tend to make extreme judgments about people or events to resolve uncertainty.     * Commonality: Both personality types share a general intolerance of out-groups and a deep respect for legitimate authority figures.

• Research on Personalities and Conviction Rates:     * Narby, Cutler, and Moran (1993): A meta-analysis of $20$ studies found that authoritarianism was reliably but modestly associated with verdict preferences; high authoritarianism correlates with a greater tendency to convict.     * Contextual Dependency: The relationship between authoritarianism and conviction can be low or non-existent depending on the specific facts of the case, highlighting the importance of context.

• Jury-Level Impacts:     * Juries with a high proportion of authoritarian or dogmatic jurors tend to convict more often (McGowen & King, 1982; Shaffer & Case, 1982) and impose longer sentences (Shaffer, Plummer, & Hammock, 1986).     * Authoritarian jurors are more likely to support prison sentences twice as long as those suggested by low-authoritarian counterparts.

• Studies on Jury Dynamics:     * Shaffer et al. (1986): In a study of juries composed of mostly dogmatic or non-dogmatic members, all nine juries that resulted in a "hung" status contained at least one non-dogmatic juror who refused to be swayed. The mean dogmatism score within a jury correlated strongly with sentence length ($r = 0.54$).     * Shaffer & Case (1982): Found that convicting juries had a significantly higher percentage of dogmatic jurors ($61\%$) compared to juries that voted to acquit ($33\%$).     * Conformity: High-authoritarian jurors are more susceptible to group conformity pressure and authority figures; they are more likely to change their verdict preferences during deliberation (Lamberth, Krieger, & Shay, 1982).

Jury Nullification and Judicial Instructions

• Nullification Definition: Juries possess the implicit power to acquit defendants despite sufficient evidence and judicial instructions to convict. This acts as a safeguard against laws perceived as unfair or unjust. It involves acquitting a defendant believed to be guilty "beyond a reasonable doubt" based on grounds of conscience.     * Examples: Cases involving environmental and peace activists, or the medical use of cannabis.

• Experimental Study on Instructions (Kerwin and Shaffer, 1991):     * Standard Instructions: "It is your duty to accept these instructions and to apply the law as it is given to you. You are not permitted to change the law, nor apply your own conception of what you think the law should be. In reaching your verdict, you must not be influenced by any consideration of sympathy or prejudice."     * Nullification Instructions: "Although you, as a jury, are a public body bound to give respectful attention to the laws, you have the final authority to decide whether or not to apply a given law… You represent your community, and it is appropriate to consider the feelings of the community, and your own feelings based on conscience…"     * Results: Verdicts by non-dogmatic juries were unaffected by the instruction type. However, dogmatic juries were highly conviction-prone under standard instructions but highly likely to acquit when nullification instructions were provided.

• Status and Remorse Interaction (Niedermeier et al., 1999):     * Nullification instructions generally made juries less likely to convict.     * An interaction effect was observed: high-status defendants (e.g., doctors) received more acquittals when showing no remorse, while low-status defendants were acquitted more often when they showed a great deal of remorse.

The Impact of Juror Experience

• Subsequent Trials: There is some support for the idea that jurors are affected by prior service; they may be more likely to favor conviction in subsequent trials (Reed, 1965).

• Cognitive Effects:     * Kerr (1981): Found no impact of prior experience when jurors considered nine armed robbery scenarios in succession.     * Kassin and Juhnke (1983): In mock juries with mixed experience levels, inexperienced jurors were found to be more likely to change their votes.

• Archival Research:     * Dillehay and Nietzel (1985): Studied $175$ trials and found the number of experienced jurors was positively correlated with conviction rates.     * Werner et al. (1985): Observed only a weak relationship across $206$ trials.     * Contrast Effect (Kerr, Harmon, and Graves, 1982): Experienced jurors appear to compare the evidence in the current trial to the strength of evidence seen in previous trials.

Juror Demographics: Gender, Social Class, and Age

• Juror Gender:     * General findings suggest male jurors are often more punitive than female jurors (Batchelder, Koski, & Byxbe, 2004; Haney, 2005).     * Exceptions: Female jurors are more punitive in sexual assault cases (Anwar, et al., 2017; Osborn, et al., 2018) and stalking cases (Dunlap et al., 2012, 2015).

• Juror Social Class:     * Keil and Vito (1991): Higher income jurors tend to judge defendants more harshly and support severe punishments.     * White Collar Crime: Low-income jurors judge white-collar defendants more harshly (Rebovich & Jiandani, 2000; Rebovich & Kane, 2002).

• Juror Age:     * Sealy (1981): Found a tendency for both younger ($18\text{--}25$) and older ($40+$) jurors to acquit; middle-aged jurors were most likely to judge perpetrators harshly.     * Higgins, Heath, and Grannemann (2007): Older jurors ($55\text{--}90$) believed defendants were more responsible for their situations and were more confident in their decisions than younger jurors ($18\text{--}46$).     * Mossiere & Dalby (2008):         * Younger adults ($18\text{--}25$) were $2.31$ times more likely than older adults to give a guilty verdict.         * Middle-aged adults ($30\text{--}45$) were $3.31$ times more likely to provide a "not guilty" verdict than the younger group.         * Younger adults were $3$ times more likely to recommend probation, while middle-aged adults showed a non-significant preference for prison.

Racial Diversity and Jury Composition

• Group Dynamics: Group composition affects performance, but evidence is inconsistent. While conflict and decreased cohesion are cited as negative outcomes (DeDreu & Wringart, 2003), diversity can also improve creativity, information sharing, and flexibility (Nela & Gruenfeld, 2004).

• Sommers (2006) Study:     * Methodology: Used $6$-person juries (all-white vs. diverse with $4$ whites and $2$ blacks) watching a video of a Black defendant charged with sexual assault. Questioning involved either race-neutral or race-relevant prompts.     * Pre-deliberation Results: Black participants ($23\%$) were less likely to vote guilty than White participants ($44\%$). Whites in diverse groups were significantly less likely to vote guilty than Whites in all-white groups even before discussion occurred.     * Post-deliberation Results: Heterogeneous groups deliberated longer and considered a wider range of information. White participants in heterogeneous groups raised more facts, made fewer factual errors, and were more open to discussing race.

The Role of Emotion in Juror Decision-Making

• General Impact: Emotions largely impede rational judgments (Feigenson, 2000; Nunez et al., 2015). Gruesome evidence (e.g., photos) can trigger disgust, lowering the threshold for "beyond reasonable doubt" (Kassin & Garfield, 1991).

• Judicial Intervention: Judges instruct jurors to look at photographs in a "calm, deliberate, and dispassionate fashion," emphasizing that emotion should not be used (Cush Goodman-Delahunty, 2006).

• Gruesome Evidence Statistics (Bright & Goodman-Delahunty, 2004): Exposure to gruesome evidence resulted in a $34\%$ guilty rate, compared to $14\%$ for non-gruesome evidence.

• Directional Processing and Mood Congruency: Emotions may cue decision-makers to attend to information consistent with their emotional valence (Bower, 1981; Forgas & Bower, 1987).

• Specific Emotional Effects:     * Anger: Leads individuals to consider fewer factors, be more prone to blaming others (Lerner, Goldberg, & Tetlock, 1998), and rely on heuristic cues (Bodenhausen, 1993).     * Sadness vs. Anger: Keltner, Ellsworth, & Edwards (1993) found angry individuals attribute outcomes to dispositional factors (individual choice), while sad individuals attribute outcomes to situational factors.     * Effect Size: A preliminary meta-analysis by Park & Feigenson (2015) suggests the average size of emotion effects on legal responsibility judgments is modest to moderate.