Effects of inadmissible Evidence on the Decisions of Simulated Jurors: A Moral Dilemma

In a 2 × 3 design, simulated jurors received either weak or strong evidence against a defendant in a murder case. Within each evidence condition, subjects were given either additional evidence ruled admissible, additional evidence ruled inadmissible, or no additional evidence. Results indicated that ( a ) jurors were biased by inadmissible evidcnce in the weak-evidence but not in the strong-evidence condition, ( b ) strong evidence resulted in more guilty verdicts than did weak evidence, ( c ) confidence in verdict was influenced by strength of evidence, and ( d ) confidence of guilt was positively correlated with severity of punishment. Implications of the results are discussed within the context of the judicial process.     

The Direct and Indirect Effects of Inadmissible Evidence1

College students (N= 270) assigned to six-person mock juries read summaries of a murder trial and then evaluated the defendant's guilt both before and after group discussion. The strength of the prosecution's case was manipulated, as was the inclusion of extra wiretapping evidence that favored the prosecution or the defense and was ruled admissible or inadmissible by the judge. Whether it favored the prosecution or the defense, inadmissible evidence directly biased subjects' reactions toward the defendant and indirectly biased their behaviors during the group discussions. None of these effects varied with the strength of the prosecution's case. The results also showed that the direct effects of inadmissible evidence were at least partially mediated by its indirect effects, suggesting that the process of deliberation can potentially help jurors to control the influence of inadmissible evidence on their decisions.     

The effect of jury deliberations on jurors' propensity to disregard inadmissible evidence

The goal of this research was to examine the effect of jury deliberations on juror's propensity to disregard inadmissible evidence. Extant research is inconclusive; some research indicates that jurors do follow judicial instructions to ignore inadmissible evidence, but other research suggests that jurors do not. Two experiments examined whether jurors were affected by inadmissible evidence. The results revealed that although mock jurors were biased by inadmissible evidence prior to deliberations, the bias was tempered following deliberations. In Experiment 1, post deliberation jurors disregarded incriminating evidence that was ruled inadmissible because of due-process concerns. Experiment 2 replicated these results with less incriminating inadmissible evidence and also revealed that jurors did not accurately gauge the impact that the inadmissible evidence had on their verdicts. Theoretical and judicial policy implications are discussed.     

Differential Male and Female Responses to Inadmissible Sexual History Information Regarding a Rape Victim

Two experiments were conducted to assess the effects of exposure to sexual activity information regarding a rape victim. The results of the first experiment indicated that men had a greater tendency to attribute a female target person's sexual activity to dispositional causes than did women. In the second experiment, subjects read an acquaintance rape scenario suggesting that the victim had a promiscuous sexual past. They were instructed either to ignore this sexual history information when making judgments (inadmissible condition) or to use whatever information that they felt was appropriate (admissible condition). Control subjects were given no information regarding the victim's sexual past. Thus, the design was a 2 (Sex of Subject) x 3 (Information Admissibility: Admissible, Inadmissible, or Control) factorial. The results indicated: (a) When compared to those in the inadmissible condition, victim perceptions from subjects in the admissible condition were less favorable, (b) victim perceptions from male subjects were less favorable than those from female subjects, and (c) male subjects in the inadmissible condition attributed more responsibility to the victim than did the controls whereas female subjects in the inadmissible condition attributed less responsibility to the victim than did controls. Possible bases of these findings are discussed.     

Guilty or Innocent? Women's Reliance on Inadmissible Evidence in a Simulated Rape Case

This study investigated the extent to which women disregard inadmissible evidence in a simulated rape case as a function of when they receive a judge's global legal instructions concerning presumption of innocence, burden of proof, reasonable doubt, and inadmissible evidence. We hypothesized that participants would be more likely to disregard incriminating inadmissible evidence when the instructions were given before rather than after the trial. Participants listened to audiotaped excerpts from a rape trial. They were given pretrial, predeliberation, or both sets of instructions; and received admissible or inadmissible avidence or no prior rape testimony, after which they made judgments. The results supported hypothesis that pretrial instructions are more effective than predeliberation instructions in allowing participants to disregard inadmissible evidence.
One cannot unring a bell; after the thrust of a saber, it is difficult to say forget the wound; and finally, if you throw a skunk into the jury box, you can't instruct the jury not to smell it ( Dunn v. United States , 1962 , p. 886).     

Trivial persuasion in the courtroom: the power of (a few) minor details

Investigated the influence of trivial testimonial detail on judgments of 424 undergraduates who served as mock jurors. Ss read a summary of a court case involving robbery and murder. In Experiment 1, detailed testimony influenced judgments of guilt, even when the detail was unrelated to the culprit. In Experiment 2, detailed testimony was especially powerful when an opposing witness testified that she could not remember the trivial details. Subsequent analyses suggest that the impact of detailed testimony on guilt judgments is mediated by inferences about the eyewitnesses. When eyewitnesses provided more detail, they were generally judged to be more credible, to have a better memory for the culprit's face and for details, and to have paid more attention to the culprit.     

How jurors use and misuse character evidence

The Federal Rules of Evidence allow defendants to offer testimony about their good character, but that testimony can be impeached with cross-examination or a rebuttal witness. It is assumed that jurors use the defense's character evidence (CE) to form guilt and conviction judgments but use impeachment evidence only to assess the character witness's credibility. Two experiments tested these assumptions by presenting mock jurors with various forms of CE and impeachment. Participants made trait ratings for the character witness and defendant and guilt and conviction judgments. Positive CE did not affect guilt or conviction judgments, but cross-examination caused a backlash in which judgments were harsher than when no CE was given. Using path analysis, the authors tested a model of the process by which CE and impeachment affect defendant and witness impressions and guilt and conviction judgments. Implications for juror decision making are discussed.     

A preliminary inquiry into the effect of potentially biasing information on judges and jurors in civil litigation

The American system of civil procedure presumes that judges and jurors will respond quite differently to potentially biasing material introduced into adjudicatory proceedings. Judges are assumed to possess a special capacity to control their subjective reactions to such material while jurors are perceived as incapable of such control. This article first reviews these presumptions and the differential treatment accorded judges and jurors by the system. An experiment in which judges and jurors were exposed to potentially biasing material in a civil trial is then described. The results suggest that judges and jurors may be similarly influenced by such exposure, regardless whether the biasing material is ruled admissible or inadmissible. The implications of these preliminary data—that judges may not possess the presumed special capacity to remain immune to bias—are briefly discussed.     

Aversive racism in Britain: the use of inadmissible evidence in legal decisions

The aversive racism framework (S. L. Gaertner & J. F. Dovidio, 1986 ) suggests that bias against Blacks is most likely to be expressed by Whites when it can be explained or justified along non‐racial grounds. The present experiment adopted a 2 (Evidence: admissible vs. inadmissible) × 2 (Defendant Race: White vs. Black) between subjects design, asking White participants, whose self‐reported prejudice was assessed, to judge a legal case. As predicted, increased guilt ratings and longer sentencing recommendations were forwarded for the Black (vs. White) defendant only when DNA evidence linking the defendant to the crime had previously been ruled inadmissible. This result was not qualified by self‐report racial attitudes. The implications for evidence inadmissibility in interracial contexts are considered, along with the repercussions of finding experimental evidence of aversive racism outside of North America. Copyright © 2005 John Wiley & Sons, Ltd.     

Victim Impact Testimony and Juror Judgments: The Effects of Harm Information and Witness Demeanor1

Victim impact testimony (i.e., testimony concerning the harmful consequences on the victim's surviving family) was examined to determine its effect on the sentencing judgments of mock jurors. Undergraduate students (N= 293) watched a videotaped murder trial simulation, rendered verdicts, and made sentencing judgments. During the penalty phase of the trial, participants were either given no victim impact testimony, or they were given victim impact testimony that varied both the severity of the harm information (mild harm/ severe harm) and the demeanor of the witness (low affect/high affect). The results indicate that information concerning the harm experienced by the victim's relatives, not the affective demeanor of the witness, influenced sentencing judgments. Implications for the U.S. Supreme Court decision in Payne v. Tennessee (1991) are discussed.     

Will jurors correct for evidence interdependence in their verdicts? It depends

Throughout an investigation, pieces of evidence are likely to contaminate one another, yet at trial jurors are expected to treat pieces of evidence as if they are independent. Are jurors able to understand potential evidence contamination? The present study showed mock jurors a videotaped trial simulation. Participants were randomly assigned to hear testimony regarding one piece of evidence, two pieces of independent evidence, or two pieces of interdependent evidence. The study tested the hypothesis that jurors who hear evidence that is interdependent will be just as likely to find the defendant guilty as jurors who hear about two pieces of independent evidence. When an eyewitness's identification was the uncontaminated piece of evidence, our hypothesis was supported. However, when the confession was the uncontaminated piece of evidence, jurors seemed to understand that one piece of evidence had been influenced by another and adjusted their beliefs about the defendant's guilt accordingly. This study supports the conclusion that jurors can sometimes identify and correct for evidence contamination in their perceptions of a defendant's guilt. Implications for reform support are discussed.     

The Impact of A Discredited Key Witness

An experiment was conducted in order to assess the impact of discredited testimony presented by a key witness in a court setting. One of two videotaped cases was presented to subjects who were asked to assume the role of jurors and to make judgments as to the defendant's liability on the basis of the evidence presented. The three possible effects of discredited testimony on judgments were examined: logic, overcorrection, and perseverance. Subjects dealt with discredited testimony logically, ignoring it, except in one version of one of the cases where the witness' discredited testimony constituted a false accusation. In this version, subjects overcorrected in their judgments.     

Degree of Detail of Eyewitness Testimony and Mock Juror Judgments1

The influence of the degree of detail of eyewitness testimony on two sides of a court case was investigated in two experiments. In the first experiment subject-jurors read a civil court case involving an automobile-pedestrian accident. The plaintiff and the defendant presented conflicting eyewitness accounts. Judgments of the relative credibility of the eyewitnesses on each side and the percentage of negligence of the parties were influenced by the relative degree of detail of the eyewitness testimony on each side. In the second experiment subject-jurors read a criminal court case involving robbery and murder. The prosecution and defense presented conflicting eyewitness accounts. The degree of detail of the prosecution eyewitness testimony influenced judgments of guilt and judgments of the credibility of the eyewitnesses. An examination of the reasons for verdicts and credibility judgments revealed that some subjects inferred that an eyewitness who gave testimony with a greater degree of detail had a better memory for the trivial details and the culprit than an eyewitness who gave testimony with a lesser degree of detail. Implications of these results for the legal system are discussed.     

The effects of labelling,expert testimony,and information processing mode on juror decisions in SVP civil commitment trials

Expert witnesses offering testimony in sexually violent predator civil commitment trials may use diagnostic labels that are either familiar (e.g. ‘psychopath’) or unfamiliar (e.g. ‘paraphilia’) to jurors. Using predictions based on cognitive experiential self-theory, we explored the influence of testimony type (clinical versus actuarial) and diagnostic label (psychopath versus paraphilia) on jurors motivated to adopt either an experiential processing mode (PM; in which heuristic cues may be strongly relied upon) or an analytic rational PM. Consistent with previous research, our results indicated that when given a psychopathic diagnostic label, mock jurors motivated to process information experientially were more influenced by clinical testimony, whereas mock jurors induced into a rational mode were more influenced by actuarial testimony. However, experientially oriented jurors given a paraphilia diagnostic label did not show the expected influence of clinical expert testimony, and instead were more persuaded by actuarial testimony. These findings are discussed from a judgement and heuristics cues framework. The implications of several procedural suggestions are examined. Copyright © 2009 John Wiley & Sons, Ltd.     

The effect of hypnotically elicited testimony on jurors' judgments of guilt and innocence.

Survey data from several countries indicate that many people believe that hypnosis may increase the accuracy of an eyewitness's memory; most experimental research, however, suggests that this belief is inaccurate. This study examined whether the belief could influence judgments of guilt and innocence in a simulated criminal trial. The results indicated that British undergraduates were more likely to find a male defendant guilty when told that the testimony against him had been elicited under hypnosis. Results concerning a nonhypnotic memory facilitation technique were found to be inconclusive, and the salience of hypnotically elicited testimony was ruled out as a contributory element.     

Reaction of mock jurors to testimony of a court appointed expert

A study was conducted to assess the impact of court appointed experts on the judgments of mock jurors. A civil proceeding was adopted for the experiment. Mock jurors heard testimony about a plaintiff's injury in an automobile accident. In some conditions, medical testimony for the plaintiff and defendant was provided by experts hired by each side. In other conditions, a medical expert appointed by the court testified in addition to the two adversarial experts. In one of these conditions, the court expert sided with the plaintiff; in another, the expert sided with the defendant. The plaintiff in the case was always an individual. The defendant was sometimes a corporation and sometimes an individual. The results showed that mock jurors sided with the court appointed expert in every condition except when the expert favored a corporate defendant. The results were discussed in terms of heuristic processing of persuasive information.     

The effects of rational and experiential information processing of expert testimony in death penalty cases

Past research examining the effects of actuarial and clinical expert testimony on defendants' dangerousness in Texas death penalty sentencing has found that jurors are more influenced by less scientific pure clinical expert testimony and less influenced by more scientific actuarial expert testimony (Krauss & Lee, 2003; Krauss & Sales, 2001). By applying cognitive-experiential self-theory (CEST) to juror decision-making, the present study was undertaken in an attempt to offer a theoretical rationale for these findings. Based on past CEST research, 163 mock jurors were either directed into a rational mode or experiential mode of processing. Consistent with CEST and inconsistent with previous research using the same stimulus materials, results demonstrate that jurors in a rational mode of processing more heavily weighted actuarial expert testimony in their dangerousness assessments, while those jurors in the experiential condition were more influenced by clinical expert testimony. The policy implications of these findings are discussed.     

Improving the Credibility of Child Sexual Assault Victims in Court: The Impact of a Sexual Assault Nurse Examiner

The present study investigated the influence of a sexual assault nurse examiner's (SANE's) testimony on mock juror perceptions of a child or adolescent victim of child sexual assault. Community members (N = 252, 156 females) read a fictional criminal trial summary of a child sexual assault case in which the victim was 6 or 15 years old and the prosecution presented medical testimony from a SANE or a traditional registered nurse (RN), or did not present medical testimony. Mock jurors were more likely to render guilty verdicts when a SANE testified compared with the other two testimony conditions. In addition, pro-victim judgments (e.g., sympathy toward the victim) and negative defendant judgments (e.g., anger toward the defendant) mediated this relation. Finally, cognitive network representations of the case demonstrated that the RN and no-medical-testimony groups were similar and the SANE group was distinct from the other two conditions. We discuss these results in terms of the implications of SANE testimony in child sexual assault court cases. Copyright © 2015 John Wiley & Sons, Ltd.