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.     

Revising the Factor Structure of the Juror Bias Scale: A Method for the Empirical Validation of Theoretical Constructs

The application of factor analytic techniques to explore the construct and predictive validity of a popular scale used for the identification of pretrial juror bias is herein reported. A confirmatory factor analysis (CFA) was employed on the Juror Bias Scale (JBS) scores of 301 participants, but empirical findings did not support the theoretically derived single-factor scales of Probability of Commission and Reasonable Doubt. Empirically driven alternative models were generated using exploratory factor analysis. The JBS scores of an additional 301 participants were then employed to cross-validate the initial findings using nested modeling CFA. The empirical model achieved a significantly improved fit over the theoretical model and resulted in the elimination of approximately 30% of the original items with no attenuation in the scale's ability to predict juror verdicts. Moreover, a theoretical reorganization of the items was consistent with the empirically derived model and provided a rationale for altering the scoring of the JBS which, in turn, maximized its predictive validity. The use of CFA techniques to aid in the development of scales assessing jury attitudes and biases is discussed.     

Examining the Construct Validity of the Original and Revised JBS: A Cross-Validation of Sample and Method

Factor analysis is a statistical technique that can provide an understanding of construct validity. Previous research examining the factor structure of the Juror Bias Scale (JBS) has uncovered problems in the scale's assessment of the constructs of probability of commission (PC) and reasonable doubt (RD). We here reevaluate the scale's constructs to better our understanding of the pretrial biases involved in the juror decision-making process. Importantly, previous findings have been limited to college student samples and trial material that has involved rape evidence. This study examines the construct validity of the JBS in a sample of 617 jury-eligible adults drawn from the community, and the predictive validity of the JBS is examined across 3 distinct trial scenarios. The results parallel earlier findings, indicating that although RD is a tenable and useful construct affecting juror decision-making, PC may be a less relevant pretrial bias. We therefore suggest that future research emphasize alternative constructs, such as confidence and cynicism in the criminal justice system.     

Defendant and juror race in a necessity case: An ultimate attribution error

This study investigated whether Black and White mock jurors would commit the ultimate attribution error (i.e., over-rely on dispositional explanations to understand the negative actions of out-group members) in a necessity defense case. Participants (N = 97) read a fictional looting case, in which the race of the defendant varied. Mock jurors were expected to show out-group severity through more guilty verdicts and blame attributions. Mock juror and defendant race were not significantly related to verdicts, but for the Black defendant, White mock jurors attributed more control to him, and believed he was likely to reoffend more so than did Black mock jurors. This study adds to the literature on the mechanism by which racial bias interferes with juror decisions.     

The Impact on Juror Verdicts of Judicial Instruction to Disregard Inadmissible Evidence: A Meta-Analysis

The effect on juror verdicts of judicial instructions to disregard inadmissible evidence was evaluated using meta-analysis. One hundred seventy-five hypothesis tests from 48 studies with a combined 8,474 participants were examined. Results revealed that inadmissible evidence (IE) has a reliable effect on verdicts consistent with the content of the IE. Judicial instruction to ignore the inadmissible evidence does not effectively eliminate IE impact. However, if judges provide a rationale for a ruling of inadmissibility, juror compliance may be increased. Contested evidence ruled admissible accentuates that information, resulting in a significant impact on verdicts. Suggestions for how the courts may mitigate the impact of inadmissible evidence more effectively are discussed.     

The biasing impact of pretrial publicity on juror judgments

This study examines three previously unexplored aspects of the biasing impact of pretrial publicity. First, this study tests the differential effects of several different types of pretrial publicity on juror decision making. Second, this study explores the impact the presentation of trial evidence has on biases created by pretrial publicity. Finally, the study explores the psychological processes by which pretrial publicity effects may operate. Results indicate that pretrial publicity, particularly negative information about the defendant's character, can influence subjects' initial judgments about a defendant's guilt. This bias is weakened, but not eliminated by the presentation of trial evidence. Character pretrial publicity, and both weak and strong inadmissible statements appear to operate by changing subjects' initial judgments of the defendant's guilt. This initial judgment then affects the way subjects assess the evidence presented in the trial and the attributions they make about the defendant. Prior record pretrial publicity appears to have its effects by influencing subjects' inferences about the criminality of the defendant and this is related to posttrial judgments.     

An Examination of Jury Verdicts for Evidence of a Similarity-Leniency Effect,an Out-Group Punitiveness Effect or a Black Sheep Effect

Archival data from cases adjudicated by jury in El Paso and Bexar County, Texas, were used to test whether a similarity-leniency effect, an out-group punitiveness effect, or a black sheep effect (BSE; J. M. Marques, V Y. Yzerbyt, & J. P. Leyens, 1988) influenced jury decisions. Defendant ethnicity, jury ethnic composition, and strength of evidence against the defendant were coded for 418 closed noncapital, felony cases to test their impact on trial verdicts and sentence lengths. Results indicated complex relations exist among juror and defendant characteristics and their influence on trial outcomes. No support was found for any of the theoretical models as predictors of jury decision-making. Strength of evidence was the most influential variable for both verdicts and length of sentences. Case strength, defendant ethnicity, and jury composition were related to sentence lengths.     

Understanding juror perceptions of forensic evidence: investigating the impact of case context on perceptions of forensic evidence strength

The most widely accepted model of juror decision making acknowledges the importance of both the case-specific information presented in the courtroom, as well as the prior general knowledge and beliefs held by each juror. The studies presented in this paper investigated whether mock jurors could differentiate between evidence of varying strengths in the absence of case information and then followed on to determine the influence that case context (and therefore the story model) has on judgments made about the strength of forensic DNA evidence. The results illustrated that mock jurors correctly identified various strengths of evidence when it was not presented with case information; however, the perceived strength of evidence was significantly inflated when presented in the context of a criminal case, particularly when the evidence was of a weak or ambiguous standard. These findings are discussed in relation to the story model, and the potential implications for real juries.     

Admitting evidence of a defendant's previous conviction (PCE) and its impact on juror deliberation in relation to both juror‐processing style and juror concerns over the fairness of introducing PCE

Purpose. To examine the impact of admitting previous conviction evidence (PCE) on juror and jury deliberation. Major questions are: (1) Is there is an association between the inclusion of PCE and confidence in a defendant's guilt using a relatively rich trial simulation? (2) Does PCE invoke jurors’ considerations of fairness to the defendant? (3) Is heuristic processing (HP) associated with a prejudicial interpretation of evidence? Methods. In experiment 1 (n= 82), individual jurors were asked to recall evidence, express opinion, and justify verdicts on the two counts of Affray and Grievous Bodily Harm (GBH). In experiment 2 (new n= 121), PCE information was emphasized and a jury deliberation condition was included. Results. There was no simple association between admitting PCE and judgements of guilt. However, both interviews and jury deliberations indicated careful consideration of evidence. In particular, juror arguments showed that some were troubled by PCE, which they saw as unwarranted and therefore unfair to the defendant. Finally, HP was associated with both a prejudicial focus on the defendant's character and a higher confidence in guilt. Conclusions. A simple link between PCE and judgements of guilt may only hold in relatively circumscribed experimental simulations. Results also indicate that the introduction of PCE is unlikely to aid evidence‐based deliberation without careful testing of different forms of judges’ explanation concerning PCE.     

Some individual differences in perception of the evidence and the verdict choice

Abstract

For the last century, social research has provided evidence that contradicts the idea of objectivity in judicial procedure. As a result, research on jurors' potential bias has emerged. We propose an alternative to traditional jury, one in which social researchers collaborate with judges and lawyers, providing them with information on the juror bias. Legal authoritarianism is one of the characteristics of personality, which seems to be linked to juror verdicts. We present two studies, which develop a specific measure for this variable. The first study shows the relevance of legal authoritarianism as a variable to describe the psychological profile of juror-eligible respondents. The second study explores the relationship between legal authoritarianism and interpretation of the evidence, as well as the potential of this variable to predict verdicts.     

Strength of Evidence,Extraevidentiary Influence,and the Liberation Hypothesis: Data from the Field

To examine relationships between strength of evidence (SOE) and extraevidentiary variables in the context of Kalven and Zeisel’s (The American Jury, 1966) liberation hypothesis, post-trial questionnaire data were collected from judges, attorneys, and jurors associated with 179 criminal jury trials. SOE ratings were strongly correlated with jury verdicts on the three most serious charges against the defendant, and several extraevidentiary variables (i.e., pretrial publicity, trial complexity, charge severity, and foreperson demographics) were moderately correlated with verdicts. Extraevidentiary-verdict relationships remained significant when SOE was controlled, although extraevidentiary variables yielded only modest improvement in classification accuracy beyond SOE. In partial support of the liberation hypothesis, several case-related extraevidentiary variables were significantly related to jury verdicts only when the prosecution’s evidence was rated as moderately strong.     

Dialect on trial: use of African American Vernacular English influences juror appraisals*

ABSTRACT

We investigated the effect of dialect and race on juror decision making. Mock jurors read a summary of an ambiguous criminal case, which included audio of a defense witness (Study 1) or defendant (Study 2). Both speaker dialect [General American English (GAE)/African American Vernacular English (AAVE)] and race (White/Black) were crossed; Study 2 also included three levels of case (Ambiguous/Pro-Prosecution/Pro-Defense) to evaluate any effects of evidentiary context. In both studies, jurors who listened to the AAVE recording found the AAVE-speaking witness to be less professional and less educated than their GAE-speaking counterparts. Interestingly, jurors in Study 2 who heard the defendant use GAE were more likely to find him guilty and found him less credible when the case favored the prosecution, hinting that ingroup biases such as the black sheep effect may also play a role in perceptions of dialect. Secondary analyses found that AAVE predicted more negative overall evaluations of the speaker, and these negative evaluations were associated with an increase in guilty verdicts. Together, these findings suggest that dialect plays an under-investigated role in the courtroom, and that bias against AAVE negatively impacts juror appraisals of its speakers and can potentially influence juror decision making.     

The CSI Effect and the impact of DNA evidence on mock jurors and jury deliberations

ABSTRACT

The present research examined the CSI Effect and the impact of DNA evidence on mock jurors and jury deliberations using a 3 (Crime Drama Viewing: low, moderate, high)?×?3 (Evidence: DNA innocent, DNA guilty, no DNA control) design. A sample of 178 jury-eligible college students read a case of breaking and entering. Pre-deliberation, some support for a CSI Effect was found with high viewers’ extent of guilt ratings significantly lower than moderate and low viewers’ in the no DNA control and the DNA innocent conditions. This effect was not present for verdicts. Contrary to a CSI Effect, crime drama viewing was not related to guilt judgments with incriminating DNA evidence. A content analysis of comments made during deliberations found little support for the CSI Effect entering the jury room. Specifically, CSI Effect predictions were not supported when examining the discussion of DNA evidence, expressing DNA opinions, or mentioning missing evidence. Overall, the limited CSI Effect found for individuals was attenuated during deliberation. The alarm raised over a possible CSI Effect influencing jury decision making may be unwarranted.     

Sexual harassment stories: testing a story-mediated model of juror decision-making in civil litigation

The story model of juror decision-making proposes that jurors use personal experience and information presented at trial to create stories that guide their verdicts. This model has received strong empirical support in studies using criminal cases. The research presented here extends the story model to civil litigation and tests a story-mediated model against an unmediated model of jury decision-making. In Phase 1, content analysis of mock juror responses to 4 realistic sexual harassment cases revealed prototypic plaintiff and defense stories. In Phase 2, these prototypic stories were included as mediators in a model predicting verdicts in 4 additional sexual harassment cases. Mock juror attitudes, experiences, and demographics were assessed, then attorneys presented abbreviated versions of 4 actual sexual harassment cases. Path analyses provided support for the story-mediated model, which added significantly to the amount of variance accounted for in the outcome measures of verdict, commitment to verdict, and confidence times verdict. Implications for sexual harassment and other types of civil cases are discussed.     

“陪审”一词的西来与中译

陪审、陪审员等不是中文固有词汇,而是西学东渐背景下之舶来品。这一组词汇的中文翻译和定型差不多纵贯整个十九世纪,历经中译名混乱的知识性介绍时期——中国知识精英向外寻求真理的中译名模仿时期——推进政制改革的中译名定型时期——《会审章程》和立宪修律中译名进入法案成为法定名等四个过程。陪审制作为一项司法审判制度在清末修律中试图加以移植,可能借鉴了日本的某种经验,但陪审、陪审员作为一组中文译名并非经日本转手才进入中国,它们在中国的翻译和定型应主要归功于以上海公廨为载体的域外法律制度的位移、来华外籍人士和传教士的传播西法西制的努力和本土有识之士的推动。     

The objective reality of evidence and the utility of systematic jury selection

Significant relationships between jurors' demographic characteristics, attitudes, and verdicts have stimulated an interest in systematic jury selection. However, critics of this approach argue that verdicts are based on the strength of the evidence presented rather than on the composition of the jury. This analysis of demographic and attitudinal data and the responses to a vignette collected from a jury-eligible sample explores the association between perception of strength of evidence and both case-relevant attitudes and demographic characteristics and then examines the amount of variation in verdict explained by juror characteristics when strength of evidence is already taken into account. The findings point to the inclusion of strength of evidence in systematic jury selection procedures.     

Fostering Juror Comfort: Effects of an Orientation Videotape

The purpose of the present study is to assess the impact of a juror orientation videotape on juror knowledge of the legal system and comfort levels regarding jury service. Juror knowledge and comfort were measured using the Juror Knowledge and Comfort Scale (JKCS). It was hypothesized that jurors exposed to the orientation videotape would be significantly more knowledgeable about the legal system and significantly more comfortable with their role as jurors. It was further hypothesized that there would be a significant correlation between the knowledge scale and comfort scale of the JKCS. Results indicate that jurors exposed to the orientation videotape scored significantly higher on both the knowledge scale and comfort scale than jurors not exposed to the orientation videotape. There is also a significant correlation between the juror knowledge and comfort components of the JKCS. The implications of the findings and directions for future research are discussed.     

Predicting verdicts,adherence to judge's instructions,and assumptions about the disposition of the defendant in a case involving the insanity defense

Abstract

296 college students and jury eligible adults completed attitudinal measures and read a case summary of a murder trial involving the insanity defense. The case summary included opening and closing arguments, testimony from expert witnesses, and judge's instructions. Although broader legal attitudes (the PJAQ) predicted verdicts, the Insanity Defense Attitudes-Revised scale provided incremental predictive validity. Attitudes related to the insanity defense also predicted adherence to judge's instructions, whereas more general legal biases predicted a juror's willingness to change their verdict after being provided with accurate information about the defendant's disposition following the verdict. Importantly, misconceptions concerning the insanity defense impacted verdicts and many jurors made decisions that failed to adhere to the judge's instructions, though the nullification tendency does appear to vary as a function of pretrial juror attitudes. Implications for instructing jurors in insanity defense cases will be discussed.     

The effects of attorney presentation style,attorney gender,and juror gender on juror decisions

Extralegal characteristics of attorneys may play a significant role in the decision-making behavior of jurors. Presentation style, for example, is one factor to which trial lawyers pay a great deal of attention. However, a given style of speech may not be perceived equivalently when used by different speakers. The present study examined the effects of the defense attorney's presentation style and gender, and juror gender on jurors' verdicts and evaluation of the attorney and witness. Undergraduate college students read a brief summary of an assault-and-robbery case, viewed a videotape of either a passive or aggressive male or female attorney interrogating a witness, then rendered a verdict and rated the witness and attorney on characteristics such as competency, credibility, and assertiveness. The results indicated that, overall, aggressive attorneys were more successful at obtaining an acquittal for their clients than passive attorneys, and that male attorneys were more successful than female attorneys; presentation style also interacted with gender of attorney and juror. Some possible mechanisms for these effects are discussed.     

Chaos in The Courtroom Reconsidered: Emotional Bias and Juror Nullification

A widespread presumption in the law is that giving jurors nullification instructions would result in "chaos"-jurors guided not by law but by their emotions and personal biases. We propose a model of juror nullification that posits an interaction between the nature of the trial (viz. whether the fairness of the law is at issue), nullification instructions, and emotional biases on juror decision-making. Mock jurors considered a trial online which varied the presence a nullification instructions, whether the trial raised issues of the law's fairness (murder for profit vs. euthanasia), and emotionally biasing information (that affected jurors' liking for the victim). Only when jurors were in receipt of nullification instructions in a nullification-relevant trial were they sensitive to emotionally biasing information. Emotional biases did not affect evidence processing but did affect emotional reactions and verdicts, providing the strongest support to date for the chaos theory.