Decision making in joined criminal trials: The influence of charge similarity,evidence similarity,and limiting instructions

The present research investigated decision-making processes in joined trials of multiple offenses. Subjects judged videotaped trials of three joined charges in a factorial design that varied charge similarity, evidence similarity, and judges' instructions designed to reduce judgement biases; or judged one of several charges presented individually. The results indicated that subjects were more likely to convict a defendant in a joined trial than on the same charge tried by itself, particularly when the charge was presented in the third position. Convictions were more frequent when joined charges were similar, and judges' instructions significantly reduced conviction rates. Subjects judging joined trials confused evidence among charges, rated the prosecution's evidence as stronger, and rated the defendent less favorably than subjects judging single trials. The findings were compared statistically to the results of previous research, and it was concluded that increased convictions in joined trials are robust effects.This research is based on part of a doctoral dissertation by S. Tanford at the University of Wisconsin. The research was supported by National Institute of Justice Grant No. 81-LJ-CX-0048 to S. Penrod.     

The influence of prior record evidence on juror decision making

Several researchers have investigated the impact of evidence of prior convictions on jurors' decision making. Very little is known about a related issue, the impact of prioracquittal evidence introduced by the prosecution on jurors' decisions. The Supreme Court recently held (Dowling v. U.S., 1990) that the admission of prior acquittal evidence does not unfairly prejudice the defendant. We conducted a simulation study to examine the effects of prior record evidence (prior convictions, prior acquittals, and no prior record) on jurors' decisions. We also manipulated the presence of judicial instructions on the limited use jurors can make of extrinsic acts evidence. Mock jurors were more likely to convict the defendant when they had evidence of a prior conviction than when they had evidence of a prior acquittal or no record evidence. This effect was mediated by attributions about criminal propensity. Judge's limiting instructions were ineffective in guiding jurors' use of prior record evidence.     

On the inefficacy of limiting instructions

The rationale for allowing into evidence a defendant's criminal record asserts that such evidence can be used for the limited purpose of impeaching a dèfendant witness's credibility and, in accord with judges' instructions, will not be used to assess likelihood of guilt. The effect that the defendant's prior record has on mock jurors' assessments of credibility and guilt was tested in a two (cases) x four (type of prior conviction) factorial design. Adults' ratings of the defendant's credibility did not vary as a function of prior record and were consistently the lowest of the credibility ratings of all witnesses. Conviction rates did vary by prior record, however, with the highest conviction rate occurring when the prior conviction was the same as the present charge and the lowest conviction rate occurring in the no-prior-conviction condition. Defendants with a previous conviction for perjury or a dissimilar crime were convicted at an intermediate rate. We concluded that the risk of prejudice to the defense under existing policy is greater than the unrealized potential benefit to the prosecution.Portions of this research were presented at the 90th Annual Convention of the American Psychological Association in Washington, D.C., August 23–27. 1982. The authors wish to thank Norman Berkowitz, Edward Krupat, and Marianne LaFrance for their comments on an earlier draft of this paper, and Hon. Robert J. Hallisey for providing us with sample instructions and for his counsel. Of course,the authors accept the responsibility for what they did, found, and concluded.     

Considering forensic science: individual differences,opposing expert testimony and juror decision making

Two experimental studies examined the effect of opposing expert testimony on perceptions of the reliability of unvalidated forensic evidence (anthropometric facial comparison). In the first study argument skill and epistemological sophistication were included as measures of individual differences, whereas study two included scores on the Forensic Evidence Evaluation Bias Scale. In both studies participants were assigned to groups who heard: (1) no expert testimony, (2) prosecution expert testimony, or (3) prosecution and opposing expert testimony. Opposing expert testimony affected verdict choice, but this effect was mediated by perceptions of reliability of the initial forensic expert's method. There was no evidence for an effect on verdict or reliability ratings by argument skill or epistemology. In the second experiment, the same mediation effect was found, however scores on one subscale from the FEEBS and age also affected both verdict and methodological reliability. It was concluded that opposing expert testimony may inform jurors, but perceptions of the reliability of forensic evidence affect verdict, and age and bias towards forensic science influence perceptions of forensic evidence. Future research should investigate individual differences that may affect perception or bias towards forensic sciences under varying conditions of scientific reliability.     

Procedural justice and ethical decision making

Procedural justice, in the form of voice and respectful treatment by supervisor, and ethical decision making are examined in this research. Ethical decision making is hypothesized to be a direct function of moral intent, as indicated by willingness to use moral criteria in decision making. Moral intent is, in turn, expected to be a function of the decision-making context, including perceptions of voice, respect and trust between supervisor and subordinate, and moral climate. Individual moral development is also expected to have a positive effect on moral intent. Results generally support the model, with two exceptions. First, perception of voice has a negative effect on moral intent, while caring climate and respectful supervisory relations have the expected positive effect on moral intent. These results suggest either a compensatory model of ethical decision making or a complacency effect. Second, individual characteristics had very little effect on either the decision made or the level of moral intent developed, save for one decision. These results suggest an important overlooked variable, the salience of issues for procedural justice concerns.     

Jurors' interpretations and jury decision making

In arriving at their verdicts, jurors must determine what really happened in the case at hand. Their interpretations then guide their decision making and become influential in the group deliberation process. This article uses conversational data from simulated jury deliberations to describe jurors' practice of articulating schematic interpretations as accounts for their verdict choices, and as means for persuading other jurors. As jurors contribute additional interpretations during deliberations, the group decision-making task becomes more complex, deliberations las longer, and they are more difficult to resolve. A significant negative relation is established between the number of interpretations articulated and the jury's likelihood of reaching a unanimous verdict. Articulating multiple interpretations in support of a candidate verdict appears to militate against its unanimous adoption.I am endebted to Andre Modigliani and Joseph Sanders for their invaluable assistance on this project.     

Bail decision making and pretrial detention

Bail practices became the target of reform efforts during the 1960's and 1970's not only because of issues concerning economic bias against indigent defendants but also because of criticism of the bail decision itself. Questions were raised about the appropriate uses of bail (e.g., to prevent flight or pretrial crime, or to inflict pretrial punishment), the rationality of the criteria relied on by judges in deciding bail, and the discretionary allocation of pretrial detention through high cash bail. In this article, case law and statutes governing bail practices in the United States are reviewed first to characterize the ambiguous legal framework from within which bail judges must operate. Then bail decisions in a large urban jurisdiction are analyzed as a case study to discover the factors most influential in determining pretrial release options. It is inferred that, even after years of reform, community-ties measures do not play a major role in the bail decision or the determination of pretrial custody; rather, the nature of the charged offense appears most influential. A finding of special significance is that a large proportion of these decisions could not be explained systematically (i.e., a large share of variance remained unexplained). The article concludes by suggesting a guidelines approach to bail that could narrow disparity in bail options and the use of detention, enhance the rationality of the decision process and contribute to more equitable pretrial practices.Revised version of a paper presented at the annual meeting of the American Psychological Association, Toronto, August, 1978. This research was supported, in part, by a grant from the Statistics Division of the Law Enforcement Assistance Administration to the Criminal Justice Research Center. Points of view or opinions stated are those of the authors and do not necessarily represent the official position of policies of the U.S. Department of Justice.     

Race and the decision making of juries

The relationship between race and jury decision making is a controversial topic that has received increased attention in recent years. While public and media discourse has focused on anecdotal evidence in the form of high‐profile cases, legal researchers have considered a wide range of empirical questions including: To what extent does the race of a defendant affect the verdict tendencies of juries? Is this influence of race comparable for jurors of different races? In what ways does a jury's racial composition affect its verdict and deliberations? The present review examines both experimental and archival investigations of these issues. Though the extant literature is not always consistent and has devoted too little attention to the psychological mechanisms underlying the influence of race, this body of research clearly demonstrates that race has the potential to impact trial outcomes. This is a conclusion with important practical as well as theoretical implications when it comes to ongoing debates regarding jury representativeness, how to optimize jury performance, jury nullification and racial disparities in the administration of capital punishment.     

A methodology for predicting the effects of changes in civil commitment decision making

We review a three-step civil commitment model and formulas for calculating the probability of release from commitment and the relative importance of the three steps in determining the outcome. New formulas are developed which enable predictions to be made about the effects of changes on the outcome of the three steps on the release probability. With the use of data from Oregon's civil commitment process, we present an example of the application of the methodology and conclude with a discussion of its major administrative and research implications.     

Race and decision making within juvenile justice: The importance of context

Previous tests of the influence of race on decision making within juvenile justice proceedings have traditionally focused on case-level variables and/or macrolevel factors that characterize the jurisdictions under study. Often excluded are measures of the attitudinal context within which decision making occurs. Using a revised conflict perspective that incorporates the role of racial stereotyping, hypotheses are developed centering on racial differences in case processing decisions within four midwest jurisdictions. Attitudes of juvenile court officials toward the punitiveness of the juvenile court and perceptions regarding differences between the behavior and attitudes of whites and those of African Americans are included in additive and race interactive models of five decision-making stages. Results indicate both lenient and harsh treatment of African Americans compared to whites. Hypotheses regarding racial stereotyping in the decision-making process receive some support and the discussion focuses on how inconsistent racial effects may be a function of variation in structural “coupling” across system decision points.     

The impact of battered woman syndrome evidence on jury decision processes

The impact of battered woman syndrome testimony on jury decision processes in trials of battered women who kill their abusers was investigated in two separate studies. It was hypothesized that the presence of the testimony would influence jurors' verdicts via its mediating effect on the jurors' interpretations of the battered woman's beliefs and actions and that its impact would vary as a function of the degree to which it was linked to the woman on trial. In Experiment I, subjects read a homicide trial involving a battered woman who had killed her husband. They received either no expert testimony (control), expert testimony presenting general research findings on the battered woman syndrome (general expert), or expert testimony in which the expert supplemented the general information with an opinion that the defendant fit the syndrome (specific expert). The presence of the specific expert, compared to the control, led to interpretations that were more consistent with the woman's account of what occurred; these interpretations, in turn, were related to more lenient verdicts. Experiment 2 investigated the effects of the testimony on small groups of deliberating jurors. Compared to the control condition, a moderate shift in verdicts from murder to manslaughter was found in both expert conditions. Content analyses of the deliberations, as well as postdeliberation judgments, indicated that the presence of the testimony led to interpretations that were more favorable to the battered woman's claim of self-defense.Preparation of this research, was supported in part by Fellowships from the Social Sciences & Humanities Research Council of Canada and the Law and Social Science Program of Northwestern University. I. wish to thank Neil Vidmar and James Olson for their invaluable advice throughout all stages of the research, as well as Shari Diamond, Tom Tyler, Richard Lalonde, and Doug McCann for their helpful comments, on earlier drafts of the article. For their diligence and patience in coding the data, I would like to thank Cindi Chandler and Audi Grant.     

Juvenile court intake decision making: The importance of family affiliation

Based on an analysis of official records and systematic observations of intake hearings, this study empirically evaluates the criteria employed in determining whether a juvenile is petitioned to court for a formal hearing and if petitioned, whether he or she is held in preadjudicatory detention. Attention is paid to legal, social, demeanor-related, and demographic variables as they impinge on intake decision making. The major finding of this study is that the farther one goes into the intake decision-making process, the more does family disaffiliation become the prominent independent variable. The article places this area of research within relevant criminological paradigms (positivist, interactionist, neo- Marxist), summarizes the existing empirical findings, and integrates theory and evidence with the goal of producing a statement on this screening stage in the juvenile justice endeavor.