The Influence of Gender and Age in Mock Juror Decision-Making

Annik Mossière
University of Calgary
J. Thomas Dalby
University of Calgary

Abstract
This study examines the influence of demographic variables on mock juror decision-making in a case of psychopathy. The gender of a fictitious criminal defendant who was labeled a psychopath was manipulated in order to examine the potential prejudicial impact on mock juror’s decision-making. Additionally, juror demographics (gender, age, and education level) were used to identify the source of bias. Participants read a fictitious manslaughter scenario followed by a psychologist’s expert testimony. Participants were asked to make a decision regarding the guilt of the defendant, and if applicable, specify the sentence the guilty defendant should receive. Findings from previous research looking at gender bias were not replicated, however, results showed a significant interaction between juror age and verdict/sentencing type. The youngest age group recommended a guilty verdict and a sentence of probation more often than the older age groups. In contrast, the older age groups were more likely than the youngest age group to give a verdict of not guilty, and sentence of incarceration (when a guilty verdict was given). These results raise concerns regarding views of the justice system when a designation of psychopathy is involved, as well as differences in cognitive processing that occur across ages.
Keywords: Juror decision-making, biases, psychopathy, gender, age



The Canadian Charter of Rights and Freedoms states that all persons accused of a crime have a right to a fair trial by an impartial jury. In determining fairness, it is essential that cognitive biases and prejudices do not interfere with juror decision-making. The jury system is predicated on the assumption that jurors are able to consider and evaluate the evidence presented at trial, and make rational decisions based on that information. In recent years, however, psychological research has suggested that people often take into account various factors outside of the content of relevant legal facts (such as testimony at a trial) when reaching decisions; therefore, unconsciously allowing biases to occur (Bornstein & Rajki, 1994; Mazella & Feingold, 1994; Edens, Desforges, Fernandez, & Palac, 2004; McKimmie et al., 2004; Colwell, 2005; Edens, 2006; Porter & Wrightsman, 2007). For example, research suggests that people rely on decisional shortcuts such as heuristics derived from peripheral cues, particularly when they do not have the ability or motivation to process complex information (McKimmie et al., 2004). Heuristics can be explained as mental shortcuts that allow people to solve problems and make judgments quickly and efficiently. Although mental shortcuts can be useful in simplifying complex events, they are also unconscious tools that can lead to serious errors in logic and reasoning. This is especially true when they replace the deeper, more controlled processing that is required in certain decision-making contexts, such as that of court cases (Colwell, 2005). In following, Porter and Wrightsman (2007) state: “a fundamental principle of social psychology is that each of us perceives the world in an idiosyncratic way”. Two different jurors will interpret the same stimulus differently, based on their past experience or training. These discrepancies based on personal experience create wide discretion in the application of the law at every stage in the process (Colwell, 2005). The phenomenon of juror bias refers to the assumption that each juror makes interpretations based on past experience and that these interpretations may influence verdicts (Porter & Wrightsman, 2007).
Certain stereotypes are made about typical criminal behavior, and this has led to biases towards gender, and the designation of psychopathy (Guys & Edens, 2003, 2006). Psychopathy is a controversial psychological construct that is currently being used by expert witnesses to enlighten decision making within the court systems of the United States, Canada, and Europe (DeMatteo & Edens, 2006; Edens, Colwell, Desforges, & Fernandez, 2005; Zinger & Forth, 1998). Psychopathy is defined as a personality disorder characterized by a severe affective deficit, lack of respect for the rights of others and the norms of society (Woodworth & Porter, 2007). Guy and Edens (2003, 2006) identified that male defendants labeled as “psychopaths” are likely to be found guilty more often than female psychopathic defendants; and female jurors are more likely to find the defendant guilty more often than male mock jurors (Guys & Edens, 2003, 2006).
One of the most essential tasks in the field of psychology and law is to recognize the common stereotypes held regarding criminals, and to identify the individuals or groups who have the potential to use these biases in court. ForsterLee and colleagues (2006) state that the literature supports the contention that juror and defendant characteristics (such as race and gender) influence the information processing by jurors through social stereotypes, and that the reliance on these characteristics may have important implications for verdict outcomes. Past studies have shown a gender difference in verdict decisions, with some studies finding women to be more conviction prone than men (ForsterLee et al., 2006; Mills, & Bohannon, 1980). These studies demonstrated that females, relative to males, are more empathic and emotionally sensitive, tend to sympathize more with the victim, and hence render harsher penalties. Males, on the other hand, are more evidence-driven in their evaluation of trial facts, identify more with the defendant, and allocate lenient decisions.
As mentioned, much attention has been given to the gender of the defendant and of the jurors. To date, however, juror age has been widely ignored in the literature. The following questions draw much interest with regards to juror age: Is there a difference in decision-making across age groups? Can we identify which age groups are most likely to form biases? What are the underlying factors that lead some ages to be more biased than others? What can the justice system do to reduce biases?

Procedure
Participants
A total of 239 participants (119 males and 120 females) drawn from a university and a community sample were used in this study. Equal numbers of males and females fell in three age groups: 18-25 years, 30-45 years, or 46-60 years. There were no significant differences in age between males and females within each age group (all p > .05).
Measures
Participants were given one of two versions of a manslaughter scenario (non-intentional homicide); one had a male defendant (Robert Hill), and the other had a female defendant (Rachel Hill). The manslaughter scenario described an incident in which the defendant allegedly pushed the victim (no gender specified) during a heated argument, consequently leading to the victim’s death. Accordingly, the defendant was being charged with manslaughter and was awaiting trial. Following the manslaughter scenario, the participants were provided with a report made by a fictitious expert, appointed to the court to assess the mental status of the defendant. The expert testimony stated that the defendant had met the criteria for “psychopathy”. Participants were also given definitions of pertinent terms, including “psychopathy”. Please see Appendix A for the complete manslaughter scenario, expert testimony, and definitions. Participants were then given a question concerning the guilt of the defendant and asked: “Based on the information supplied above, do you believe that the defendant is guilty of manslaughter beyond a reasonable doubt?” Participants were asked to decide between two provided answer choices “guilty” or “not guilty”, and were required to choose one. Based on their answer on the first question, only participants who chose “guilty” were told to move onto the second question. This question asked: “Should the defendant be convicted of manslaughter, what sentence do you believe should be given and how long do you think that sentence should be?” Participants were provided with two options, “a term of incarceration” or “a term of probation” of which they were required to choose only one and specify the length of the term. Additionally, participants were asked to provide some basic demographic information about themselves, including age, gender, education, and occupation.

Results
Forward Logistic Regression analyses were conducted using SPSS 15.0, in order to predict the probability of the defendant’s verdict being guilty versus not guilty, and the probability of sentencing type, incarceration versus probation. These analyses were done using four predictor variables (defendant gender, juror gender, education level, and age group). Education was later removed from the analysis to combat the potential problems associated with low cell counts.
The first analysis conducted was conducted to predict the probability of verdict, with 239 selected cases included in the analysis. This analysis identified that it could be correctly predicted 69.5% of the time that the youngest age group would be 2.31 times more likely than the older age group to give a verdict of guilty, B = .84, W = 2.2, p < .05. Conversely, it could be correctly predicted 69.5% of the time that the older age group would be 2.31 times more likely than the youngest age group to give a verdict of not guilty, B = -.84, W = 2.2, p < .05. In addition, it could be correctly predicted 69.5% of the time that the middle age group would be 3.31 times more likely than the youngest age group to give a verdict of not guilty, B = -1.12, W = 3.22, p < .005.
The second analysis conducted was formulated to predict, based on the guilty verdicts, the probability of sentencing, with 163 select cases included in the analysis (total of guilty verdicts). This analysis identified that it could be correctly predicted 63% of the time that the youngest age group would be 3.00 times more likely than the older age group to give a sentence of probation, B = 1.09, W = 2.72, p < .05. Conversely, it could be correctly predicted 63% of the time that the older age group would be 3.00 times more likely than the youngest age group to give a sentence of incarceration, B = -1.09, W = 2.2, p < .05. The middle age group was not significant; however, it followed the same trend as the older age group, where it showed preference to a sentence of incarceration rather than probation.

Discussion
Although this study did not replicate findings from previous research, and did not find significant gender effects, the frequencies of judgments follow trends similar to that of previous research: Male defendants were found guilty slightly more often and given harsher sentences than female defendants. Additionally, female jurors were somewhat more likely to provide guilty verdicts than male jurors. For overall verdict and sentencing frequencies, see Table 1.

Table 1.
Observed Frequencies of Guilty Verdicts and Sentences of Incarceration
Moc juror.JPG

Overall, significant effects of verdict and sentence type were found – where jurors were more likely to say guilty than not guilty, and more likely to give a sentence of incarceration than probation. It is important to highlight that there was a significance interaction between decision-making and mock-juror age. Results showed that the youngest age group would be most likely to assign a guilty verdict and that the older age groups would be most likely to give a sentence of incarceration. The decisions made by mock-jurors and the age effects found in this study could be explained by the composition of the sample. This study utilized a more representative sample drawn from the community, which seems to have had a significant influence on the findings. Although findings from previous research were not replicated, this may be due to the fact that many of the previous studies were drawn from only a university sample, generally comprised of psychology undergraduate students.
The significant differences in decision-making lay between the age groups. Further research and exploration would be necessary in order to appropriately explain these results, however, one could conjecture that the differences between age groups could be due to a number of reasons: differing life experience, confidence, cognitive processing, or views of the justice system. By looking and the judgments made by the youngest age group, we can identify a sense of uncertainty or a lack of confidence in their decisions: younger jurors said guilty more often than the other age groups, but tempered their guilty verdict by choosing a sentence of probation more often than incarceration. This indicates that the younger mock jurors may have lacked the maturity and confidence to follow through with their convictions, demonstrating a more fluid, or fluctuating, view of the justice system. In contrast, when the older age groups chose a verdict of guilty, they were more confident and consistent in their sentencing, choosing incarceration more often than probation. This consistency demonstrates their more crystallized, or solidified, view of the justice system. These results support findings by Boatright (2001) who asked citizens “do you feel you know enough about how the legal system works to be a fair and impartial juror?” and found that the youngest cohort was the least confident about their skills as jurors. In the same article, it was suggested that younger citizens also have an overall lower level of confidence in courts than do older citizens. It is important to identify the basis of differences in decision-making across ages because it could provide key information on the foundation of biases and can give insight into the types of education or interventions needed to combat biases in the courtroom. Strategies to prevent biases could be uniquely developed depending on the root of the bias, for example, education could have an significant impact if the bias is rooted in a juror’s lack of experience, confidence, or in negative views of the justice system. Further research identifying and explaining biases would be required in order to develop prevention and education strategies.
Although verdicts cannot always be predicted simply by knowing the demographic configuration of the jury, a demographic profile can be useful in understanding and predicting juror attitudes and group tendencies. Findings from this type of research can provide key information on how to deal with biases. Knowing that younger jurors are most likely to give a guilty verdict allows for opportunities to challenge pre-existing misconceptions that this age group may have towards people labeled as psychopaths, and the legal system in general. In addition, knowing that middle-aged men are the most likely to give a verdict of not guilty would most likely be of great interest to both the prosecution and the defense dealing with this kind of case. This type of research can have a great impact on society because it deals directly with the legal rights of people. Research of this type is conducted with the goal of ensuring individuals’ right to a fair trial, and keeping judgments and rulings free of bias. The current study aimed to gain a greater understanding of the types of biases that occur in court. Although gender biases were not found, age showed to play a significant role in the types of decisions made by mock jurors. Decisions made by jurors under 25 years of age differed significantly from decisions made by jurors over the age of 30. Findings from this type of research can provide key information to the courts on how to deal with skewed verdicts and on how to avoid potential biases.

Future Directions
A potential limitation to this study lies within the design. Contrary to actual jury proceedings, our mock jurors did not have the opportunity to deliberate among themselves. Whether the effects of gender would have been more pronounced when filtered through the discussions within group deliberations that appear to foster a division in opinions was not assessed, and would be interesting to explore qualitatively in future research. ForsterLee and colleagues (2006) suggest that groups are more sensitive to biasing information than individuals, providing support for examination of this issue in future studies. The idea of using a group mock-design would allow researchers to discuss complex issues and to get extended feedback. The information that one receives from peers can be quite helpful in deciding issues around case strategy, and this could provide researchers with qualitative information identifying why participants chose certain verdicts and sentences. Difficulties with group mock-trials occur in the sample and in the recruitment process. Problems with mock trials in general include the fact that it is difficult to obtain a representative sample; the sample sizes are far smaller and it takes skill to develop an adequate script.
Another potential limitation of this study concerns the ability to generalize the results, given the stimulus materials. Although the trial transcript used in this study was not very detailed in order to specifically examine juror bias, simulated jury research has been criticized because the trial materials are often brief relative to real trials. Drawing from suggestions by ForsterLee and colleagues (2006) and Mills and Bohannon (1980), as to why women may be more conviction prone than men, the answer may rest in the emotionality of the case. These studies demonstrated that females, relative to males, are more empathic and emotionally sensitive, tend to sympathize more with the victim, and hence render harsher penalties. Males, on the other hand, are more evidence-driven in their evaluation of trial facts, identify more with the defendant, and allocate lenient decisions. The simplicity and lack of detail of the scenario in the current study may be an explanation for why no juror gender bias was found. The scenario provided no information that may trigger juror emotion, therefore leaving out the key factor that may be the source of juror gender judgment differences.
While juror age, gender, and education were considered in this study, other factors that were not examined might have played an important role. Additional demographic information such as race, religious affiliation, or political stance may be influential in the decision-making process. In addition to these demographic variables, it would be interesting consider qualitative data of mock-juror comments or thoughts, which may provide further insight into the rationalization and reasoning behind their decisions. Participants often wanted to know additional details such as perpetrator aggression levels or rationale behind the incident. Participants also often asked for further details, including situational context, personal history of the victim and/or defendant, and previous convictions of the defendant. While the researcher could not provide any supplementary information to such questions, participants were left to their life-experiences and heuristics to form conclusions. In the current study, it was not possible to know specifically the thought process of the participants considered, and the use of qualitative data may help to address this issue.

Conclusion
The intent of this study was to examine the influence of defendant and juror demographics on juror decision-making. The significance of examining decision-making lies in recognition that biases do occur, and therefore can impede a person’s right to a fair trial. This study provided empirical results demonstrating that there are differences in decision-making across age groups. It has also shed some light on identifying those age groups most likely to form biases, and what the underlying factors might be (i.e. younger age groups, perhaps because of lack of education or experience). The significant age effect found in this study can contribute information in predicting verdicts based on demographics. Results from this research suggest that we can predict in almost 70% of manslaughter trial cases when the defendant is a “psychopath”, that middle-aged men will be most likely to give a verdict of not guilty. The results of this study provide essential information for the courts by highlighting the importance of educating jurors on potential biases, and informing trial consultants hired by either the prosecution or the defence for the jury selection process. The findings from this study can provide key information to the courts when dealing with skewed verdicts and potential biases. The next step would be for the justice system to apply these findings, and develop ways in which we could reduce/avoid biases in court.

References
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Appendix A
Definition Sheet
Manslaughter: The unlawful killing of another person without premeditation or so-called “malice aforethought” (an evil intent prior to the killing).
It is distinguished from murder (which brings greater penalties) by lack of any prior intention to kill anyone or create a deadly situation.
Psychopathy: a personality disorder that is characterized by severe affective deficit and a lack of respect for the rights of others and the norms of society
Personality disorder: an enduring pattern of inner experience and behavior that differs markedly from the expectations of the individual’s culture, is pervasive and inflexible, has an onset in adolescence or early adulthood, is stable over time, and leads to distress or impairment. Personality disorders are a long-standing and maladaptive pattern of perceiving and responding to other people and to stressful circumstances.
Beyond a reasonable doubt: part of jury instructions in all criminal trials, in which the jurors are told that they can only find the defendant guilty if they are convinced “beyond a reason- able doubt” of his or her guilt.
Probation: a chance to remain free (or serve only a short time) given by a judge to a person convicted of a crime instead of being sent to jail or prison, provided the person can be good. Probation is only given under specific court-ordered terms, such as performing public service work, staying away from liquor, paying a fine, maintaining good behavior, getting mental therapy and reporting regularly to a probation officer
Fictitious Manslaughter Scenario and Expert Witness Testimony
On July 28th, 2005 at 12:37 am, Calgary Police were dispatched to the second block of 13th Avenue S.W. for a report of a person found dead. The death of the victim was alleged by witnesses to have resulted from an altercation between the victim and Robert Hill, where it is said that a heated argument ensued. Robert Hill is alleged to have pushed the victim who subsequently fell down toward the pavement, resulting in the victim’s head hitting the curb. Currently, Robert Hill has been charged with manslaughter and now awaits trial.
The following is an excerpt from the written report made by Dr. Jansen, an expert appointed by the court to assess the mental status of the defendant:
The Psychopathy Checklist – Revised (PCL-R) was also used to assess Robert Hill. This assessment instrument is used to diagnose psychopathy – a personality disorder that is characterized by a severe affective deficit and a lack of respect for the rights of others and the norms of society.
The PCL-R is composed of 20 items that are scored individually on a scale of 0 (not present) to 2 (definitely present), and ratings for each item are based on both an interview with the patient and supplementary information that has been obtained. Furthermore, the checklist is comprised of two factors: the first assesses the callous disregard for the rights of others and the second assesses persistent antisocial behavior.
After the completion of the PCL-R, I have come to the conclusion that Robert indeed has a psychopathic personality disorder. In other words, Robert meets the criteria of psychopathy, displaying an enduring, pervasive and stable pattern of behavior and experience that deviates noticeably from the expectations of our society.
I have reached this conclusion because he received a score above the cutoff point of 30 for psychopathy. First, Robert scored especially high on Factor 1 items. More specifically, he demonstrated high scores on the following items of the PCL-R:
- Glibness/superficial charm
- Grandiose sense of self-worth
- Pathological lying
- Conning/manipulative
- Lack of guilt or remorse
- Shallow affect
- Callous/lack of empathy
- Failure to accept responsibility for own actions

Biographical Notes
Annik M. Mossière graduated from the University of Calgary in 2007 with a BA in Psychology. She hopes to pursue graduate studies in Forensic Psychology. Her research interests include young offenders, competency to stand trial, children’s suggestibility, false confessions, and suicide motivations in delinquent youth.
e-Mail: amossier@ucalgary.ca
J. Thomas Dalby is Adjunct Professor (Psychology and Clinical Psychology) and Adjunct Associate Professor (Psychiatry) at the University of Calgary. He is the author of over 100 professional publications including Applications of Psychology in the Law Practice (American Bar Association 1997). He has practiced in forensic psychology and neuropsychology for over 30 years and is a Fellow of the Canadian Psychological Association.