The consistency of inconsistency in serial homicide: patterns of behavioural change across series

Linkage analysis is a crucial part of the investigative process when faced with a possible series of related offences. Establishing behavioural consistency (i.e., offender's behaviours consistently present across the series) is at the core of linkage. Recent empirical studies have found little evidence of consistency looking at either individual or groups of behaviours in serial homicide. It is argued that behavioural changes are rooted in the changing cognitive strategies that offenders use to reach their ultimate goal (i.e. the commission of multiple homicides). Factors that could account for these changes include learning, situational factors, loss of control, and changes in the offender's fantasy. Patterns of behavioural change have been identified in serial crimes, such as rape. However, no empirical studies have looked at patterns of behavioural change in serial homicide. The present study examined patterns of consistency and change using a combination of thematic and behavioural subgroup approaches that use Multidimensional Scaling. Thematic differentiation indicative of behavioural manifestations of cognitive strategies was found in all three examined subgroups: planning, wounding, and offender–victim interaction, and patterns of change within these subgroups provided support for the above theories. Looking at behavioural patterns rather than individual behaviours, may be a more fruitful way of examining consistency in serial homicide, and could have significant implications for linkage analysis. Copyright © 2010 John Wiley & Sons, Ltd.     

A qualitative analysis of mock jurors' deliberations of linkage analysis evidence

Evidence about a suspect's behavioural similarity across a series of crimes has been presented in legal proceedings in at least three different countries. Its admission as expert evidence, whilst still rare, is becoming more common thus it is important for us to understand how such evidence is received by jurors and legal professionals. This article reports on a qualitative analysis of mock jurors' deliberations about expert linkage analysis evidence. Three groups of mock jurors (N = 20) were presented with the prosecution's linkage analysis evidence from the USA State v. Fortin I murder trial and expert evidence for the defence constructed for the purposes of the study. Each group was asked to deliberate and reach a verdict. Deliberations were video‐recorded and subject to thematic content analysis. The themes that emerged were varied. Analysis suggested that the mock jurors were cautious of the expert evidence of behavioural similarity. In some cases they were sceptical of the expert. They articulated a preference that expert opinion be supported using statistics. Additional themes included jurors having misconceptions concerning what is typical offender behaviour during rape which suggests there is a need for expert linkage analysis evidence regarding behavioural similarities and the relative frequencies of crime scene behaviours. Copyright © 2010 John Wiley & Sons, Ltd.     

The Role of Death Qualification in Jurors' Susceptibility to Pretrial Publicity1

Two hundred residents of Florida's 12^th Judicial Circuit completed questions measuring participants' level of death-penalty support, death-qualification status, knowledge of the facts surrounding an actual capital case, and attitudes toward the defendant in the aforementioned capital case. Results indicated that death-qualified participants were better able to correctly identify the defendant, recognize most of the factual details of the case, think that the defendant was guilty, and recommend the death penalty. In addition, death-qualified jurors were more likely to feel that the pretrial publicity surrounding the case would have minimal impact on the defendant's right to due process. Legal applications and implications are discussed.     

Another Look at the Impact of Juror Sentiments toward Defendants on Juridic Decisions

Abstract

This experiment tested the hypothesis that jurors' preexisting biases (sentiments) toward an accused would have a much stronger impact on the sentences that jurors recommended than on the verdicts they rendered. Specifically, a balance theory analysis of juridic decisions specifies that predeliberation sentiments toward the defendant would have little if any direct effect on jury verdicts and would be associated with verdicts rendered only if the information establishing these sentiments also implied a unit relation between the defendant and the crime. Six-person juries deliberated the case of an accused robber and murderer who had no prior criminal record, a prior conviction for a dissimilar crime, or a prior conviction for a similar crime. While on the witness stand, the defendant either withheld information or provided answers for all questions. The results provided strong support for the hypothesis. In addition, jurors' predeliberation sentiments toward the accused were unrelated either to the tone of juridic deliberations or to postdeliberation assessments of the defendant's guilt. By contrast, juror sentiments toward the defendant were a solid predictor of the severity of sentences assigned by those who voted to convict the accused.     

Behavioural linking of stranger rapes

A sample of serial stranger rape cases ( n = 43) that had occurred in Finland during the years 1983–2001 were studied with the objectives being to: (a) describe the characteristics of the offenders; (b) explore the structure of serial rape; and (c) demonstrate behavioural linkage through an analysis of the offenders' crime scene behaviour using both multidimensional scaling (MDS) and discriminant function analysis (DFA). The material was content analysed with regard to the occurrence of a number of dichotomous variables. The inter‐relationships of the variables was studied using MDS. The analysis revealed two previously identified major modes of interaction with the victim: involvement and hostility. Employing MDS and DFA, it was shown that the offences of different offenders were distinguishable in terms of variation between the offences of different offenders and consistency within the offences of a single offender. Using DFA, the classification accuracy clearly exceeds that expected by chance, and 25.6% of the cases were classified without any error. The results are discussed in relation to their practical utility and previous studies. Copyright © 2005 John Wiley & Sons, Ltd.     

Individual and Group Decisions in Response to a Mock Trial: A Methodological Note1

An audiovisual slide-show presentation of a murder trial was used to examine the effects of group deliberations on juror's responses. Sex of defense attorney and race of defendant were systematically varied in the mock trial. Verdicts were assessed immediately following the trial presentation (before group deliberations) and immediately following group deliberations. Neither sex nor race significantly affected distributions of individual juror's predeliberation verdicts. Following group deliberations, however, an effect of attorney's sex emerged in both jury (group) verdicts and in individual, postdeliberation verdicts. Jurors in the male defense attorney conditions were more likely to vote not guilty following deliberations than were jurors in the female defense attorney conditions. This effect is discussed in terms of group shift.     

The effects of body‐worn camera footage and eyewitness race on jurors' perceptions of police use of force

Police use of body‐worn cameras (BWCs) is increasingly common in the USA. This article reports the results of one of the first experimental examinations of the effects of three BWC status conditions (absent, transcribed, viewed) and eyewitness race (Black, White) on mock jurors' case judgments, in a case in which a community member (defendant) was charged with resisting arrest but where the officer's use of force in conducting the arrest was controversial. Results provide evidence of significant main effects of both eyewitness race and BWC status. When the eyewitness supporting the defendant was White, mock jurors were less likely to vote the defendant guilty of resisting arrest, as well as more likely to consider the defendant credible and the officer culpable for the incident. In addition, when BWC footage of the arrest was viewed, compared with transcribed or absent, participants were less likely to vote the defendant guilty of resisting arrest, and also rated the officer's use of force less justifiable, and the officer more culpable and less credible. Follow‐up analyses demonstrated that these relationships between BWC condition and case judgments were all mediated by moral outrage toward the officer.     

Comparing the Predictive Accuracy of Case Linkage Methods in Serious Sexual Assaults

The empirical support for linkage analysis is steadily increasing, but the question remains as to what method of linking is the most effective. We compared a more theory‐based, dimensional behavioural approach with a rather pragmatic, multivariate behavioural approach with regard to their accuracy in linking serial sexual assaults in a UK sample of serial sexual assaults (n = 90) and one‐off sexual assaults (n = 129). Their respective linkage accuracy was assessed by (1) using seven dimensions derived by non‐parametric Mokken scale analysis (MSA) as predictors in discriminant function analysis (DFA) and (2) 46 crime scene characteristics simultaneously in a naive Bayesian classifier (NBC). The dimensional scales predicted 28.9% of the series correctly, whereas the NBC correctly identified 34.5% of the series. However, a subsequent inclusion of non‐serial offences in the target group decreased the amount of correct links in the dimensional approach (MSA–DFA: 8.9%; NBC: 32.2%). Receiver operating characteristic analysis was used as a more objective comparison of the two methods under both conditions, confirming that each achieved good accuracies (AUCs = .74–.89), but the NBC performed significantly better than the dimensional approach. The consequences for the practical implementation in behavioural case linkage are discussed. Copyright © 2012 John Wiley & Sons, Ltd.     

Effects of Defendant Background and Remorse on Sentencing Judgments

Previous evidence that subject sentencing judgments are mediated by considerations of equity led to the hypothesis that defendant remorse and an impoverished defendant background would each reduce subject sentencing judgments. Results from 48 male and 48 female student subjects showed that remorse had the predicted effect ( p < .02) but background did not. Regardless of the initial manipulation, sentences shifted significantly toward leniency ( p < .02) after subjects had engaged in group discussion. The effect for remorse is consistent with the contention that the equity principle extends to psychological factors, while the leniency shift raises the possibility that jury deliberations tend to favor the defendant.     

Familiarity impacts person perception

We investigated the effects of familiarity on person perception. We predicted that familiarity would increase non‐analytic processing, reducing attention to and the impact of individuating information, and increasing the impact of category labels on judgments about a target person. In two studies participants read either incriminating or exculpatory individuating information about a defendant in a criminal case and made judgments of guilt. In Study 1, participants were subliminally exposed to the defendant's photo, another matched photo, or no photo before seeing the evidence. Participants familiar with the defendant's photo both processed and used the individuating information less. In Study 2, participants were subtly made familiar or not with the incriminating and exculpatory information itself, and the defendant was described either as a priest or as a skinhead. Familiarity with the information reduced attention to its content and also tended to increase reliance on category information in guilt judgments. Copyright © 2006 John Wiley & Sons, Ltd.     

The effect of the psychopathy checklist – revised in capital cases: Mock jurors' responses to the label of psychopathy

Despite mixed empirical evidence regarding the ability of the Psychopathy Checklist – Revised (PCL‐R) to predict violence among incarcerated inmates, it continues to be used to address such questions, even in the context of capital cases. The purpose of this study was to examine if the PCL‐R has a prejudicial effect on mock jury members during the sentencing phase of a capital murder trial. Results indicated that participants were more likely to sentence the defendant to death when the defendant exhibited a high likelihood to commit future violence, whether or not the diagnostic label “psychopath” was present. Interestingly, when asked to rate the defendant's likelihood for future violence and murder, the defendant who was a high risk for future violence and not labeled a psychopath received the highest rating. These results suggest an absence of juror bias as it pertains to the label “psychopath” when sentencing a defendant in a capital murder case. Copyright © 2010 John Wiley & Sons, Ltd.     

The Prejudicial Impact of Pretrial Publicity1

The current studies examine the influence of pretrial publicity on potential jurors' attitudes toward a defendant. In Study 1, following one year of newspaper coverage of the investigation, arrest, and indictment of defendants for distributing large quantities of marijuana in southern Illinois, 604 potential jurors in that district were surveyed regarding their knowledge of the case, general attitudes toward crime, and attitudes toward the specific case. Analyses of the survey data revealed that knowledge of the case specifics was positively and significantly correlated with perceived culpability of the defendant but nonsignificantly correlated with willingness to admit partiality. Study 2 dealt with a highly publicized Dade County, Florida murder of a police officer in a drug sting operation. Again knowledge of pretrial publicity correlated significantly with perceived culpability of the defendant. As in Study 1, such knowledge did not correlate with stated ability to be impartial. We conclude that even modest pretrial publicity can prejudice potential jurors against a defendant and that self-reports of impartiality should not be taken at face value.     

Expert Evidence for the Practical Prosecutor

There has been a decade of legislative progress in England and Wales aimed at making children's evidence as receivable in criminal courts as is adults' and at protecting them when giving their evidence. However opinion still prevails that children are routinely traumatised by the court process. Could expert evidence help lessen the trauma for the child?     

Perceptions of Sexual Assault: The Expression of Gender Differences and the Impact of Target Alcohol Consumption1

This research examined the impact of defendant/complainant alcohol consumption and prior sexual history evidence on mock jurors' evaluations of a sexual assault trial. Participants (N = 196) were provided with a simulated trial in which the beverage consumption of both targets and the sexual history between them was manipulated. The results displayed a complex interplay between target beverage consumption and gender of participant. Typically observed gender effects—that is, women, compared to men, were more supportive of the complainant and less supportive of the defendant—was contingent upon target beverage consumption. Depending on how aggressive participants perceived the defendant to be, women were more sympathetic to the complainant, with this being contingent upon complainants' and defendants' beverage consumption.     

From Compassion to Compensation: The Effect of Injury Severity on Mock Jurors' Liability Judgments1

Two studies were performed to ascertain the effect of injury severity on participants' judgments in a simulated jury task. Participants read a summary of a personal-injury case in which the severity of the plaintiffs injury was varied; they were asked to judge the defendant's liability, award compensation. and rate their feelings toward the litigants. In Study I, more severely hurt plaintiffs were more likely to obtain a favorable verdict, even though evidence of liability was held constant. Greater severity influenced liability judgments only insofar as it elicited positive feelings toward the plaintiff or negative feelings toward the defendant, In Study 2, severity was found to have no effect when participants could not award damages, suggesting that more severe injuries arouse feelings for the litigants that are associated with a motivation to alleviate the plaintiffs suffering or to punish the defendant. Strategies for reducing the extralegal influence of injury severity are discussed.     

Perceptions of Children's Credibility in Sexual Assault Cases1

Children's testimony often plays a central role in prosecutions of child sexual abuse. Nevertheless, research on jurors' perceptions of the credibility of child sexual assault victims remains limited. In three experiments, we examined mock jurors' reactions to children's testimony about sexual abuse. Participant jurors were exposed to videotaped or written scenarios of child sexual abuse trials and then rated victim credibility and defendant guilt. Analyses indicated that: (a) victim age was either inversely related or unrelated to perceptions of victim credibility, (b) women were more likely than men to find child victims credible, (c) corroborating testimony from a child victim increased the credibility of another child victim, and (d) exposure of participants to past criminal acts and other negative defendant character evidence heightened perceived victim credibility and defendant guilt. Implications for understanding jurors' reactions to child witnesses are discussed.     

How a “Reasonable Doubt” Instruction Affects Decisions of Guilt

Jurors are instructed to render a guilty verdict if they feel the defendant is guilty beyond a reasonable doubt. The jury is often told that this does not mean an absolute certainty of guilt and that even if it were possible to imagine a scenario in which the defendant is innocent, a guilty verdict may still be appropriate. Here, participants read a case summary. They were either told to say that the defendant was guilty if they believed in guilt beyond a reasonable doubt or were given more detailed instruction stressing that they did not have to be absolutely certain of guilt to give a guilty verdict. In Experiment 1, participants provided “think-aloud” protocols. Content analysis revealed that those who were given this instruction often used the phrase reasonable doubt to justify their guilty verdicts by saying that although they were not certain of the defendant's guilt, their belief exceeded the reasonable doubt threshold. None of the participants in the control group did this. Experiment 2 was designed to test if the instruction affected belief in guilt and the reasonable doubt threshold quantitatively. The instruction affected both people's belief in guilt and the threshold that they used to define reasonable doubt. The implied values for reasonable doubt were 63% for those who received the instruction and 77% for the control group. Implications for jury decision making are discussed.     

THE EFFECTS OF DEFENDANT AND COMPLAINANT INTOXICATION ON MOCK JURORS' JUDGMENTS OF SEXUAL ASSAULT

The present study investigates the impact of participant gender, rape-myth beliefs, and alcohol intoxication on the part of either the defendant and/or alleged victim on mock jurors' decisions within the context of a sexual-assault trial. Participants ( N = 152) were exposed to a sexual-assault case in which the beverage consumption (alcohol, cola) on the part of both the defendant and complainant prior to the sexual intercourse was varied systematically. Results indicated that when the defendant had consumed alcohol, as opposed to cola, participants were more likely to view the case as one of assault, to perceive the defendant as less credible, and to find the defendant guilty. When the complainant had consumed alcohol, as opposed to cola, participants found the complainant's claim less credible and were less likely to view the defendant as guilty. In addition, participants' rape-myth acceptance, which was related to guilt, mediated the relation between gender of participant and guilt.     

The use of a linkage analysis as evidence in the conviction of the Newcastle serial murderer,South Africa

The linking of a series of crimes to one individual has always been problematic, especially in the absence of eyewitness or forensic evidence. During the investigation, another means whereby this can be done is through linkage analysis. Yet a linkage analysis can also play a role during the trial of a serial offender. This paper examines the use of a linkage analysis report as evidence during the trial of the Newcastle serial murderer in South Africa. The linkage analysis examined the circumstances of the crime, modus operandi, and signature behaviour of the offender, to come to the conclusion that all the offences were committed by one individual, despite the lack of eyewitness or forensic evidence linking the suspect to two of the four incidents. This evidence was admitted by the court and the presiding officer concurred that the accused was guilty of committing the crimes during the third and fourth incidents. Copyright © 2006 John Wiley & Sons, Ltd.