This study examined about 500 mock juror perceptions in a murder trial in which the defendant claims to have killed her abusive husband in self-defense. The defendant’s psychological diagnosis, the husband’s alcohol abuse history, and documentation of domestic violence were varied across conditions. Results showed that medical evidence of domestic violence had a significant effect on guilt ratings and on perceptions of blame for the husband’s death. History of alcohol use of the husband influenced mock jurors’ perceptions of the credibility of the defendant. Juror gender effects were also found on verdict ratings. In contrast, no main effect was found for the defendant’s diagnosis.

The current study was based on Brown and Jacquin’s (2010) study of juror bias in rape trials, except that group deliberation was utilized in examining mock juror verdicts. Specifically, this study examined the influence of type of rape (stranger or acquaintance), complainant alcohol consumption, and defendant alcohol consumption on the opinions of mock jurors (N = 224). Type of rape and defendant alcohol consumption did not impact mock juror responsibility attributions or guilt ratings before or after group deliberation. However, complainant alcohol consumption significantly impacted mock juror opinions before and after group deliberation. Complainants who were intoxicated at the time of the alleged rape were viewed as more responsible for the rape. Defendants were viewed as more responsible when the complainant was sober at the time of the alleged rape. The results indicate a need for jurors and the courts to be aware of juror biases about female alcohol consumption.

This program of research examined whether mock-jurors could more accurately discriminate between correct and false eyewitness identifications after exposure to the identification procedure instead of—or in addition to—the witness’s testimony. In Experiment 1, 332 eyewitnesses exposed to staged crime videos attempted to identify the “criminal” from lineups. Lineups contained either the “criminal” or a replacement foil, were presented simultaneously or sequentially, and were conducted under double-blind, single-blind, or post-identification feedback conditions. In Experiment 2, 432 mock-jurors viewed a subset of the eyewitnesses from Experiment 1 (n = 48). Each mock-juror viewed a single eyewitness making their identification decision and/or testifying about the crime, their identification, and the officer. More mock-jurors believed that the eyewitnesses had made correct identifications if they viewed the testimony—with or without the identification procedure—compared to exposure to the identification procedure alone. Furthermore, more mock-jurors believed eyewitnesses who received post-identification feedback or had made their identifications from sequential lineups. These differences in belief, however, did not translate into a difference in accuracy; overall, mock-jurors believed 62.96% of correct identifications and 56.48% of false identifications. Exposure to the identification procedure did not improve mock-jurors ability to determine the accuracy of an identification; however, these mock-jurors were more aware of the post-identification feedback. Videotaping identification procedures may make triers of fact more aware of biased lineup procedures; nonetheless, exposure to these videotapes will not improve the accuracy of mock-jurors’ decisions. / Thesis (Ph.D, Psychology) -- Queen's University, 2008-07-24 15:00:30.512

Despite the high prevalence rates of rape, the rates of reporting, arrest, and conviction for this crime are quite low. To help remedy this problem, it is important to study factors that influence juror decisions in rape trials. The purpose of the current study was to investigate the influence of three independent variables, type of rape, complainant alcohol consumption, and defendant alcohol consumption, on mock juror verdicts. Participants were randomly assigned to one of eight conditions varying on the three independent variables. Participants were surveyed about their perceptions of rape myths, alcohol beliefs, defendant guilt, and complainant and defendant responsibility. Overall, the complainant’s alcohol consumption had a larger effect on guilt ratings and perceptions of complainant and defendant responsibility than the defendant’s alcohol consumption and the relationship between the victim and defendant. Jurors’ beliefs about alcohol also correlated with perceptions of the situation, complainant, and defendant.

abstract: Deoxyribonucleic Acid (DNA) evidence has been shown to have a strong effect on juror decision-making when presented in court. While DNA evidence has been shown to be extremely reliable, fingerprint evidence, and the way it is presented in court, has come under much scrutiny. Forensic fingerprint experts have been working on a uniformed way to present fingerprint evidence in court. The most promising has been the Probabilistic Based Fingerprint Evidence (PBFE) created by Forensic Science Services (FSS) (G. Langenburg, personal communication, April 16, 2011). The current study examined how the presence and strength of DNA evidence influenced jurors' interpretation of probabilistic fingerprint evidence. Mock jurors read a summary of a murder case that included fingerprint evidence and testimony from a fingerprint expert and, in some conditions, DNA evidence and testimony from a DNA expert. Results showed that when DNA evidence was found at the crime scene and matched the defendant other evidence and the overall case was rated as stronger than when no DNA was present. Fingerprint evidence did not cause a stronger rating of other evidence and the overall case. Fingerprint evidence was underrated in some cases, and jurors generally weighed all the different strengths of fingerprint testimony to the same degree. / Dissertation/Thesis / M.S. Psychology 2012

Although rape is prevalent in the United States, conviction rates for perpetrators are low. Before developing a solution for low conviction rates in rape cases, researchers must examine factors that influence juror decisions in rape trials. The current study investigated the influence of complainant substance use and juror education about rape myths and sexual consent laws. Mock jurors were randomly assigned to one of twelve conditions and after reading the rape trial summary were asked to rate defendant guilt and complainant and defendant blameworthiness and credibility. Mock jurors in the education condition rated the defendant as significantly guiltier and more to blame for the sexual assault than did mock jurors in the no education condition.

In this thesis I combine the social network analysis approach with the traditional experimental approach to study the phenomena of jury decision-making. I examine whether with each trial a social network is formed. The jurors, the two teams of lawyers, as well as the accused and the judge, all form a social network with cliques and leaders. This division of individuals into specific cliques, along with the lawyers' performance in court, is hypothesized to have a significant impact on the jury's verdict. <br /><br /> Thus, by specifically studying the lawyers' engagement and disengagement on the jurors during a trial and the impact this has on the verdict, as well as understanding the structure of the social network that the individual jurors create, I hope to shed light on some of the influences that are key in delivering the verdict. In addition, this pioneering study may lead to significant policy changes in the future.

This study examined the relationships among participants’ emotional intelligence and participants’ sympathy for an alleged rape victim[1], sympathy for a defendant, and verdict in a mock rape case. Participants were 219 (127 female, 92 male) United States jury eligible individuals between the ages of 18 and 66. Participants were given a rape trial summary accompanied by a manipulated emotional facial expression of the alleged rape victim (angry, sad, afraid, or neutral), or no photograph. Participants were asked to render an individual case verdict and complete a questionnaire with measures to test sympathy for the alleged rape victim, sympathy for the defendant, self-emotional intelligence, other-emotional intelligence, and rape-myth acceptance. Results provided evidence that self and other-emotional intelligences are positively correlated; sympathy for rape victim and sympathy for the defendant do have an effect on case verdict; and, participant characteristics including gender, age, and race are predictive of rape myth acceptance, sympathy for the defendant, sympathy for the victim, and emotional intelligence. Further research should expand on emotional intelligence as a juror characteristic in the United States as well as internationally. [1] The term rape victim, rather than rape survivor, is used in this study to refer to an individual’s victim status in the context of the legal system.

Past research has investigated the cross-race effect in the context of eyewitnesses and jury decision-making. The main goal of my thesis was to gain further insight into participants’ knowledge of the cross-race effect and how this impacted participants’ discrimination of same- and cross-race identifications. One hundred fifty-nine undergraduate students from UOIT viewed a series of showup identification videos. I found that participants were better able to discriminate accurate from inaccurate same-race identifications than cross-race identifications. However, participants believed White witnesses more and found them more credible than South Asian witnesses. Further research should investigate other conditions that influence people’s abilities to discriminate accurate from inaccurate eyewitness identifications. / UOIT

In this thesis I combine the social network analysis approach with the traditional experimental approach to study the phenomena of jury decision-making. I examine whether with each trial a social network is formed. The jurors, the two teams of lawyers, as well as the accused and the judge, all form a social network with cliques and leaders. This division of individuals into specific cliques, along with the lawyers' performance in court, is hypothesized to have a significant impact on the jury's verdict. <br /><br /> Thus, by specifically studying the lawyers' engagement and disengagement on the jurors during a trial and the impact this has on the verdict, as well as understanding the structure of the social network that the individual jurors create, I hope to shed light on some of the influences that are key in delivering the verdict. In addition, this pioneering study may lead to significant policy changes in the future.