On Finding for Defendants Who Plead Insanity: The Crucial Impact of Dispositional Instructions and Opportunity to Deliberate

One hundred twenty participants functioned as mock-jurors and as members of deliberating juries in an experiment designed to assess the impact of dispositional instruction on verdicts rendered in an insanity trial. Consistent with prior research (K. E. & J. R. Ogloff, 1995), dispositional instruction had no effect on the verdict preferences of individual jurors prior to deliberating. Yet, as expected, the instruction manipulation had a major impact on postdeliberative decisions (i.e., group verdicts; individual juror verdict preferences). Content analyses of jury deliberations revealed that postdeliberative shifts toward harsh verdicts in uninstructed juries and toward lenient verdicts in instructed juries were mediated by the impact of the Instruction manipulation on the content of jury deliberations: uninstructed juries feared that an acquitted-insane defendant would be freed to act again, whereas instructed juries recognized that finding for an insane defendant implied his retention and treatment. Implications of these results for both legal policy and the conduct of mock-trial research are discussed.     

Juror Sensitivity to the Cross-Race Effect

Black and White mock jurors' sensitivity to the cross-race effect was investigated by varying the race of the eyewitness in a simulated murder trial of a Black defendant. Participants heard an audiotape of a trial after which they rendered a verdict and rated the credibility of the witnesses. White participants found the prosecution witnesses (including the eyewitness) more credible, and the defense witness less credible, than did Black participants; they were also more likely to find the defendant guilty. The Black eyewitness was perceived as more credible than was the White eyewitness, but eyewitness race had no effect on verdict. These results are consistent with the literature indicating that jurors of different races reach different verdicts, and also that jurors are relatively insensitive to factors that affect eyewitness testimony, such as the cross-race effect.     

Effects of the dynamite charge on the deliberations of deadlocked mock juries

When juries report that they are deadlocked, judges often deliver the dynamite charge, a supplemental instruction that urges jurors to rethink their views in an effort to reach a unanimous verdict. The present study evaluated the impact of this procedure on 378 subjects who participated in 63 deadlocked mock juries. Results indicated that the dynamite charge caused jurors in the voting minority to feel coerced and change their votes, reduced the pressure felt by those in the majority, and hastened the deliberation process in juries that favored conviction. These findings raise serious questions concerning the use of this controversial charge.     

Mock jurors’ perceptions of a child witness: the impact of the presence and/or intervention of a registered intermediary during cross-examination

ABSTRACT

In recent years Registered Intermediaries (RIs) have been involved in facilitating communication in children's investigative interviews and trial proceedings. Their presence and interventions are generally deemed to have a positive impact on child engagement, but their impact on jury appraisal of evidence, during cross-examination is unclear. This study addressed this issue in a more ecologically valid context than that previously used. Adult mock juror participants (N?=?217) watched a video-recording of a mock cross-examination of a child witness in which a RI was present or absent, and in which RI type interventions were either included or omitted. The participants rated the quality of the cross-examination and the child's responses in relation to child credibility, child understanding, legal professional's behaviour, and trial progression. Findings indicated that RI presence or absence, and inclusion or omission of interventions had no effect on mock juror ratings. However, an interaction between these variables demonstrated that mock jurors rated trial progression towards a guilty verdict according to which court professional did, or did, not intervene. The findings also demonstrated that mock jurors based their assessment of trial progression towards a guilty verdict on the evidence presented, and that child understanding per se was irrelevant.     

The effects of death qualification on jurors' predisposition to convict and on the quality of deliberation

This study provides a straightforward test of the proposition that people who are permitted to serve on juries in capital cases (death-qualified jurors) are more likely to convict a defendant than are people who are excluded from serving on capital juries due to their unwillingness to impose the death penalty (excludable jurors). A sample of 288 subjects classified as death-qualified or excludable under theWitherspoon standard watched a 2 1/2-hour videotape of a simulated homicide trial including the judge's instructions, and gave an initial verdict. Death-qualified subjects were significantly more likely than excludable subjects to vote guilty, both on the initial ballot and after an hour's deliberation in 12-person juries. Nine juries were composed entirely of death-qualified subjects (death-qualified juries), while 10 contained from 2 to 4 excludable subjects (mixed juries). On postdeliberation measures, with initial death-penalty attitudes controlled, subjects who had served on the mixed juries were generally more critical of the witnesses, less satisfied with their juries, and better able to remember the evidence than subjects from the death-qualified juries, suggesting that diversity may improve the vigor, thoroughness, and accuracy of the jury's deliberations.     

Effects of Judicial Instructions and Case Characteristics in a Mock Jury Trial of Battered Women Who Kill

This study examined the effects of judicial instructions on the outcome of a mock jury trial that involved a woman who pleaded self-defense after killing her abusive spouse. Jurors were instructed to adopt either an objective or a subjective standard of reasonableness when reaching a verdict. Within objective/subjective instruction conditions, half of the juries viewed a case in which the woman killed her abuser while he was attacking her (confrontational) and the remaining half viewed a case in which she killed him while he was asleep (no confrontation). Juries in the subjective conditions returned significantly more not guilty verdicts than jurors in the objective conditions. At the individual juror level, participants hearing subjective instructions were significantly more likely to rate the defendant as not guilty than jurors given objective instructions when the abuse was nonconfrontational.     

The influence of pretrial exposure to community outrage and victim hardship on guilt judgments

Although the courts have explicitly expressed concerns about the effects of public sentiment on juries in highly publicized cases, no research has isolated the degree to which jurors’ exposure to community outrage and/or prospective social interactions in the community independently influence judgments of guilt. In the current research, jury eligible undergraduates were randomly assigned to conditions in a 2 (negative defendant facts pretrial publicity (PTP): present vs. absent)?×?2 (community outrage PTP: present vs. absent)?×?2 (anticipated social interaction: present vs. absent) between subjects factorial design. In an online session, participants read articles containing PTP (or not), and two days later they arrived at the lab to serve as mock jurors in a murder case – before the trial they were instructed (or not) that they would interact with people from the community in which the case was taking place. Neither PTP containing extra-evidentiary facts about the defendant nor prospective interaction with the community had main or interactive effects on guilt measures; however, mock jurors rated the defendant as more likely to be guilty when they read information about community outrage and hardships on victims. These findings suggest future avenues of PTP research focusing on community outrage and victim impacts.     

Complex scientific testimony: How do jurors make decisions?

Critics of the civil jury system question whether jurors can adequately evaluate complex expert testimony. Based on current models of research in persuasion, we hypothesized that when expert testimony is complex, factors other than content will influence persuasion. Participants, serving as mock jurors, watched a videotaped trial in which two scientists provided evidence on whether PCBs could have caused a plaintiff's illness. The complexity of the expert's testimony and the strength of the expert's credentials were varied in a 2×2 factorial design. After watching the videotape, mock jurors rendered a verdict and completed a number of attitude measures related to the trial. Overall, consistent with our prediction, we found that jurors were more persuaded by a highly expert witness than by a less expert witness, but only when the testimony was highly complex. When the testimony was less complex, jurors relied primarily on the content of that testimony, and witness credentials had little impact on the persuasiveness of the message.     

What does “unwilling” to impose the death penalty mean anyway? another look at excludable jurors

The debate regarding the death qualification of juries usually concerns (a) whether death-qualified jurors have different attitudes and values to excludable jurors, or (b) whether death-qualified juries are more prone to convict. A pivotal question is whether excludable subjects in fact willever impose the death penalty. Subjects were presented with five grisly murder vignettes. Only 40% of excludable subjects refused to consider the death penalty in all of the cases, with the remaining 60% indicating they would consider the death penalty in one or more of the cases. It is argued that the majority of individuals currently being excluded from capital trial juries based on their reservations about the death penalty actually would impose the death penalty for serious enough offenses and that they should therefore be allowed to serve on such juries.     

Identifying and measuring juror pre-trial bias for forensic evidence: development and validation of the Forensic Evidence Evaluation Bias Scale

Abstract

Previous research has provided support for the impact of juror pre-trial bias on judicial decision making, particularly in cases where the evidence presented at trial is of weak or ambiguous probative value. In an effort to identify whether a pre-trial bias for forensic evidence exists, the Forensic Evidence Evaluation Bias Scale (FEEBS) was developed and tested. The results of a principal components analysis suggested that two distinct constructs were being measured, corresponding to a pro-prosecution and pro-defence bias toward forensic evidence. In a second validation study, scores on these two subscales were compared with other existing juror bias measures (Juror Bias Scale and Belief in a Just World) and in a mock juror decision making task only the pro-prosecution subscale of the FEEBS predicted the perceived strength of forensic evidence. A partial mediation model is presented which explains the relationship between this bias and verdict preferences. The implications of this potential juror bias are discussed in the context of real juries, the CSI Effect (which refers to anecdotal claims that jurors are biased by the popularity of fictional representations of forensic science on television) and peremptory challenges, as well as future research directions.     

Expert evidence and hearsay

In upholding the admission of expert evidence, some courts have held that hearsay information conveyed via an expert may be admitted as long as the jury is instructed to ignore the facts asserted in the hearsay statements and to use the information only for determining the weight to attribute to the expert's opinion. Results of a mock juror simulation indicated that although hearsay elements conveyed via an expert were perceived as less likely compared to a condition in which the information was independently admitted at trial, it was not completely ignored by the jurors. Further, the findings tended to suggest that the impact of the hearsay on verdict decisions operated primarily by influencing evaluations regarding the likelihood of the hearsay events as opposed to judgments regarding the expert testimony.     

The dynamite charge

When juries report they are deadlocked, judges may deliver a supplemental instruction known as thedynamite charge which urges jurors to reexamine their views in an effort to reach a unamimous verdict. To examine the impact of this instruction, 72 mock jurors were led to believe they were participating in a controlled deliberation by voting and passing notes. Subjects were randomly assigned to the majority or minority faction of a 3-to-1 split. After the third round of deliberation, half the subjects received the dynamite charge, half did not. Results provided support for the hypothesis that the dynamite charge causes jurors in the minority to feel coerced and to change their votes and encourages those in the majority to exert increasing amounts of social pressure. These findings are discussed for their practical implications, limitations, and directions for further research.We would like to thank Rebecca Buchanan and Craig Gangi for their role as experimenters in a pilot study.     

Conduct and its Consequences: Attempts at Debiasing Jury Judgments

Jurors in negligence cases are supposed to judge a defendant by the reasonableness of his or her conduct and not by the consequences of that conduct. But several studies have shown that a cognitive heuristic known as hindsight bias can skew post hoc judgments of some prior behavior. Thus, jurors who must evaluate the actions of a defendant may be influenced inappropriately by the consequences of those actions. A complementary problem arises when jurors must evaluate the injuries incurred by the plaintiff. Here, jurors' knowledge about the defendant's allegedly negligent conduct can proactively influence their assessment of the plaintiff's injuries and determination of damages. The purpose of the present study was to examine the effectiveness of two procedural techniques intended to reduce or eliminate the impact of hindsight bias in negligence cases—multiple admonitions from a judge about the proper use of evidence—and bifurcation (actually withholding irrelevant evidence from jurors). We presented a re-enacted automobile negligence trial to 355 jury-eligible adults drawn from the community, varied the evidence and instructions that they heard, and measured liability judgments and damage awards from individual jurors both before and after deliberating, and from juries. Results showed that admonitions were generally ineffective in guiding jurors to the proper use of evidence but that bifurcation was relatively more effective. Deliberations had no curative effect on jurors' misapplication of evidence.     

Educating Jurors about Forensic Evidence: Using an Expert Witness and Judicial Instructions to Mitigate the Impact of Invalid Forensic Science Testimony

Invalid expert witness testimony that overstated the precision and accuracy of forensic science procedures has been highlighted as a common factor in many wrongful conviction cases. This study assessed the ability of an opposing expert witness and judicial instructions to mitigate the impact of invalid forensic science testimony. Participants (N = 155) acted as mock jurors in a sexual assault trial that contained both invalid forensic testimony regarding hair comparison evidence, and countering testimony from either a defense expert witness or judicial instructions. Results showed that the defense expert witness was successful in educating jurors regarding limitations in the initial expert's conclusions, leading to a greater number of not-guilty verdicts. The judicial instructions were shown to have no impact on verdict decisions. These findings suggest that providing opposing expert witnesses may be an effective safeguard against invalid forensic testimony in criminal trials.     

Effects of jurors’ gender and attitudes toward intellectual disability on judgments in cases involving disabled juvenile defendants

Because many juvenile offenders are intellectually disabled and have their cases tried by jurors in adult criminal court, it is important to understand factors that influence jurors’ judgments in such cases. Using a mock trial methodology, we explored the relations among jurors’ gender, attitudes toward intellectual disability, and judgments in a criminal case involving an intellectually disabled 15-year-old girl accused of murder. Men mock jurors’ judgments were not influenced by their preexisting biases, but women's were: the more women favored special treatment for disabled offenders, the less likely they were to suspect the disabled juvenile was guilty and the less likely they were to convict her. Implications for actual cases involving disabled juvenile defendants are discussed.     

The Effects of Rehabilitative Voir Dire on Juror Bias and Decision Making

During voir dire, judges frequently attempt to “rehabilitate” venirepersons who express an inability to be impartial. Venirepersons who agree to ignore their biases and base their verdict on the evidence and the law are eligible for jury service. In Experiment 1, biased and unbiased mock jurors participated in either a standard or rehabilitative voir dire conducted by a judge and watched a trial video. Rehabilitation influenced insanity defense attitudes and perceptions of the defendant’s mental state, and decreased scaled guilt judgments compared to standard questioning. Although rehabilitation is intended to correct for partiality among biased jurors, rehabilitation similarly influenced biased and unbiased jurors. Experiment 2 found that watching rehabilitation did not influence jurors’ perceptions of the judge’s personal beliefs about the case.