Effects of Mental Health and Neuroscience Evidence on Juror Perceptions of a Criminal Defendant: the Moderating Role of Political Orientation

Neuroscience explanations really do satisfy: A systematic review and meta-analysis of the seductive allure of neuroscience

Extraneous neuroscience information improves ratings of scientific explanations, and affects mock juror decisions in many studies, but others have yielded little to no effect. To establish the magnitude of this effect, we conducted a random-effects meta-analysis using 60 experiments from 28 publications. We found a mild but highly significant effect, with substantial heterogeneity. Planned subgroup analyses revealed that within-subjects studies, where people can compare the same material with and without neuroscience, and those using text, have stronger effects than between-subjects designs, and studies using brain image stimuli. We serendipitously found that effect sizes were stronger on outcomes of evaluating satisfaction or metacomprehension, compared with jury verdicts or assessments of convincingness. In conclusion, there is more than one type of neuroscience explanations effect. Irrelevant neuroscience does have a seductive allure, especially on self-appraised satisfaction and understanding, and when presented as text.

The effect of neuroscientific evidence on sentencing depends on how one conceives of reasons for incarceration

Neuroscientific evidence is increasingly utilized in criminal legal proceedings, prompting discussions about how such evidence might influence legal decisions. The effect of neuroscientific testimony on legal decisions remains uncertain, with some studies finding no effect, others reporting that neuroscience has a mitigating impact, and some indicating neuroscience evidence has an aggravating effect. The present study attempts to explain these divergent findings by showing that the effect of neuroscience evidence on sentencing interacts with beliefs about the goals of the criminal legal system. Using a between-subjects design, participants (N = 784) were asked to assume different rationales for imprisonment, before receiving neuroscientific evidence about antisocial behavior and its potential relation to the defendant. Participants recommended a sentence for the defendant prior to and after reading the neuroscientific evidence. Participants who were given the rationale of retribution as the primary goal of imprisonment significantly decreased their sentencing recommendations. When the goal of imprisonment was to protect the public from dangerous people, participants provided longer post-testimony sentences. Lastly, when the goal was to rehabilitate wrongdoers, participants also increased sentences from pre to post. Thus, the impact of neuroscientific evidence is not monolithic, but can lead to either mitigated or aggravated sentences by interacting with penal philosophy.

COVID-19 in the Courtroom: The Role of Mask Mandates and Source of Exposure on Negligence and Recklessness Decisions

The current study examined whether business owners would be found liable for an employee’s illness from COVID-19 contracted at work. We varied whether there was a mask mandate at the time of the employee’s exposure (Yes or No), how the employee was exposed (an unmasked customer, an unmasked owner who forgot her mask, or an unmasked owner who did not require masks in her store) and measured participants’ political orientation. Participants (N = 257) read and listened to a trial transcript about an employee that contracted COVID-19 at her workplace and was suing her employer for compensation to cover hospital bills. Participants were more likely to find the defendant negligent, reckless, and responsible when a mask mandate was present and when an unmasked owner led to the employee’s COVID-19 exposure compared to an unmasked customer. Furthermore, the more conservative the participant, the less likely they were to find the defendant negligent, reckless, and responsible. In sum, presence of a mask mandate, owner exposure, and juror political orientation play an important role in civil litigation involving COVID-19.

The effects of forensic mental health reports on decisions about guilt in the Netherlands: An experimental approach

In the Netherlands, in approximately 30% of the more serious criminal cases, a pretrial forensic mental health report (FMHR) is requested to inform the court whether a mental disorder was present at the time of alleged crime, whether this disorder affected behavior and decision-making at the time of the offense and how this disorder may affect future (criminal) behavior. While informative for sentencing decisions, information about mental disorders or risk is irrelevant for the question whether the defendant committed the alleged crime. Yet based on cognitive psychological theory of evidence evaluation and integration, we hypothesized that information in an FMHR would affect the evaluation of evidence as well as the ultimate decision about guilt. Using an experimental vignette study among 200 law and criminology students with manipulation of the presence and content of an FMHR, we found a main effect of the presence of an FMHR report on decisions about guilt. The proportion of guilty verdicts increased with almost 20% when an FMHR was present compared to when this report was absent, irrespective of the type of disorder (schizophrenia or personality disorder) or level of recidivism risk (low or high) present in the report. We did not find support for our hypothesis that this effect could be explained by assimilation of other available evidence. Implications for further research and practice are discussed.

Neuroscientific evidence in the courtroom: a review

The use of neuroscience in the courtroom can be traced back to the early twentieth century. However, the use of neuroscientific evidence in criminal proceedings has increased significantly over the last two decades. This rapid increase has raised questions, among the media as well as the legal and scientific communities, regarding the effects that such evidence could have on legal decision makers. In this article, we first outline the history of neuroscientific evidence in courtrooms and then we provide a review of recent research investigating the effects of neuroscientific evidence on decision-making broadly, and on legal decisions specifically. In the latter case, we review studies that measure the effect of neuroscientific evidence (both imaging and nonimaging) on verdicts, sentencing recommendations, and beliefs of mock jurors and judges presented with a criminal case. Overall, the reviewed studies suggest mitigating effects of neuroscientific evidence on some legal decisions (e.g., the death penalty). Furthermore, factors such as mental disorder diagnoses and perceived dangerousness might moderate the mitigating effect of such evidence. Importantly, neuroscientific evidence that includes images of the brain does not appear to have an especially persuasive effect (compared with other neuroscientific evidence that does not include an image). Future directions for research are discussed, with a specific call for studies that vary defendant characteristics, the nature of the crime, and a juror’s perception of the defendant, in order to better understand the roles of moderating factors and cognitive mediators of persuasion.

Biological Evidence Regarding Psychopathy Does Not Affect Mock Jury Sentencing

Research on the biological factors influencing criminal behavior is increasingly being introduced into court, necessitating research on how such evidence is perceived and influences decision makers. Research on how this evidence influences sentencing recommendations is inconclusive. In this study, we focus on biological evidence related to psychopathy, a construct commonly associated with criminal behavior. Approximately 800 community members were presented with a case vignette detailing an individual who is described as having a high level of psychopathic traits. Participants received either psychological information about psychopathy (i.e., no biological evidence), evidence the defendant had genetic risk factors for psychopathy, or written neuroimaging evidence the defendant had brain deficits associated with psychopathy. Participants then recommended a sentence. Overall, recommended sentence lengths did not differ between evidence conditions. These findings add to a growing body of research suggesting that biological evidence may not have as much of an influence on jurors as previously thought.

Mock Juror Perceptions of Credibility and Culpability in an Autistic Defendant

One-hundred-and-sixty jury-eligible participants read a vignette describing a male who was brought to the attention of police for suspicious and aggressive behaviours and displayed atypical behaviours in court. Half of participants were informed that he had autism spectrum disorder (ASD) and were given background information about ASD; the other half received no diagnostic label or information. The provision of a label and information led to higher ratings of the defendant's honesty and likeability, reduced blameworthiness, and resulted in fewer guilty verdicts, and more lenient sentencing. Thematic analysis revealed that participants in the label condition were more empathetic and attributed his behaviours to his ASD and mitigating factors, while participants in the No label condition perceived the defendant as deceitful, unremorseful, rude and aggressive.

Dangerous, depraved, and death-worthy: A meta-analysis of the correlates of perceived psychopathy in jury simulation studies

OBJECTIVES

Experimental research suggests that legal defendants described as psychopathic are generally, although not uniformly, judged more negatively and punitively. Understanding the correlates of perceived psychopathy, regardless of exposure to mental health evidence, is an important step towards clarifying divergent findings.

METHOD

We conducted a quantitative synthesis of ten juror simulation studies (combined N = 2,980) examining the meta-analytic association between perceived defendant psychopathy and various psychologically important and legally relevant outcomes.

RESULTS

Perceiving someone as being more psychopathic was associated with viewing that defendant as more dangerous (r _W  = 0.31) and evil ( r _W  = 0.44). Moreover, perceptions of defendant psychopathy predicted greater support for more adverse consequences in terms of capital sentencing ( r _W  = 0.22) and sentence length ( r _W  = 0.27), although not perceived treatment amenability ( r _W  = 0.09).

CONCLUSIONS

These findings highlight the importance of including ratings of perceived psychopathy in experimental designs to identify the circumstances under which psychopathy evidence might prejudicially impact case outcomes.

Triarchic Model Personality Traits and Their Impact on Mock Juror Perceptions of a White-Collar Criminal Defendant

The triarchic model of psychopathy proposes that this personality disorder is composed of 3 relatively distinct constructs: meanness, disinhibition, and boldness. Although the first 2 components are widely accepted, boldness has generated considerable theoretical debate concerning its relevance-largely due to its association with various ostensibly adaptive characteristics and socially desirable behaviors (e.g., self-reported heroism). But is being bold actually perceived by others as an intrinsically adaptive, socially desirable personality trait? We investigated this question using a novel approach-a jury simulation study that manipulated the level of triarchic traits exhibited by a white-collar criminal. More specifically, 330 community members read a vignette in which the defendant's degree of boldness and disinhibition was manipulated and then provided sentence recommendations and other evaluative ratings. As hypothesized, manipulating boldness and disinhibition resulted in more negative views of the defendant, with the boldness manipulation more consistently predicting higher global psychopathy, "meanness," and "evil" ratings. Surprisingly, neither manipulation predicted sentence recommendations, although higher global psychopathy ratings did correlate with more punitive sentence recommendations. The presence of personality traits construed in some contexts as advantageous or socially desirable can be perceived as more dysfunctional and undesirable in other contexts-particularly when they cooccur with criminal behavior.