Neuroimage evidence and the insanity defense

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.

Limitations Using Neuroimaging to Reconstruct Mental State After a Crime

Neuroimaging offers great potential to clinicians and researchers for a host of mental and physical conditions. The use of imaging has been trumpeted for forensic psychiatric and psychological evaluations to allow greater insight into the relationship between the brain and behavior. The results of imaging certainly can be used to inform clinical diagnoses; however, there continue to be limitations in using neuroimaging for insanity cases due to limited scientific backing for how neuroimaging can inform retrospective evaluations of mental state. In making this case, this paper reviews the history of the insanity defense and explains how the use of neuroimaging is not an effective way of improving the reliability of insanity defense evaluations.

Re-wiring Guilt: How Advancing Neuroscience Encourages Strategic Interventions Over Retributive Justice

The increasing visibility of neuroscience employed in legal contexts has rightfully prompted critical discourse regarding the boundaries of its utility. High profile debates include some extreme positions that either undermine the relevance of neuroscience or overstate its role in determining legal responsibility. Here we adopt a conciliatory attitude, reaffirming the current value of neuroscience in jurisprudence and addressing its role in shifting normative attitudes about culpability. Adopting a balanced perspective about the interaction between two dynamic fields (science and law) allows for more fruitful consideration of practical changes likely to improve the way we engage in legal decision-making. Neuroscience provides a useful platform for addressing nuanced and multifaceted deterministic factors promoting antisocial behavior. Ultimately, we suggest that shifting normative attitudes about culpability vis-à-vis advancing neuroscience are not likely to promote major changes in the way we assign legal responsibility. Rather, it helps us to shed our harshest retributivist instincts in favor of more pragmatic strategies for combating the most conspicuous patterns promoting mass incarceration and recidivism.

Impact of an Artificial Intelligence Research Frame on the Perceived Credibility of Educational Research Evidence

Artificial Intelligence (AI) is attracting a great deal of attention and it is important to investigate the public perceptions of AI and their impact on the perceived credibility of research evidence. In the literature, there is evidence that people overweight research evidence when framed in neuroscience findings. In this paper, we present the findings of the first investigation of the impact of an AI frame on the perceived credibility of educational research evidence. In an experimental study, we allocated 605 participants including educators to one of three conditions in which the same educational research evidence was framed within one of: AI, neuroscience, or educational psychology. The results demonstrate that when educational research evidence is framed within AI research, it is considered as less credible in comparison to when it is framed instead within neuroscience or educational psychology. The effect is still evident when the subjects’ familiarity with the framing discipline is controlled for. Furthermore, our results indicate that the general public perceives AI to be: less helpful in assisting us to understand how children learn, lacking in adherence to scientific methods, and to be less prestigious compared to neuroscience and educational psychology. Considering the increased use of AI technologies in Educational settings, we argue that there should be significant attempts to recover the public image of AI being less scientifically robust and less prestigious than educational psychology and neuroscience. We conclude the article suggesting that AI in Education community should attempt to be more actively engaged with key stakeholders of AI and Education to help mitigate such effects.

Mentally disordered offenders and the law: Research update on the insanity defense, 2004-2019

The insanity defense is among the most controversial legal constructs that has attracted the attention of scholars, practitioners and policy makers. Here, we conducted a systematic review of the literature spanning 2004 to 2019 that produced 58 studies of insanity defense research. Findings are organized according to: (1) assessments and assessment-related issues, (2) juror decision-making in defense trials, (3) characteristics of insanity acquittees, (4) release recommendations for insanity acquittees, (5) revocation of conditional release status of insanity acquittees, and (6) additional areas of insanity defense research. Implications of the research for the insanity defense and cognate legal issues are proffered.

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.

The charm of structural neuroimaging in insanity evaluations: guidelines to avoid misinterpretation of the findings

Despite the popularity of structural neuroimaging techniques in twenty-first-century research, its results have had limited translational impact in real-world settings, where inferences need to be made at the individual level. Structural neuroimaging methods are now introduced frequently to aid in assessing defendants for insanity in criminal forensic evaluations, with the aim of providing "convergence" of evidence on the mens rea of the defendant. This approach may provide pivotal support for judges' decisions. Although neuroimaging aims to reduce uncertainty and controversies in legal settings and to increase the objectivity of criminal rulings, the application of structural neuroimaging in forensic settings is hampered by cognitive biases in the evaluation of evidence that lead to misinterpretation of the imaging results. It is thus increasingly important to have clear guidelines on the correct ways to apply and interpret neuroimaging evidence. In the current paper, we review the literature concerning structural neuroimaging in court settings with the aim of identifying rules for its correct application and interpretation. These rules, which aim to decrease the risk of biases, focus on the importance of (i) descriptive diagnoses, (ii) anatomo-clinical correlation, (iii) brain plasticity and (iv) avoiding logical fallacies, such as reverse inference. In addition, through the analysis of real forensic cases, we describe errors frequently observed due to incorrect interpretations of imaging. Clear guidelines for both the correct circumstances for introducing neuroimaging and its eventual interpretation are defined.

What difference do brain images make in US criminal trials?

One of the early concerns regarding the use of neuroscience data in criminal trials is that even if the brain images are ambiguous or inconclusive, they still might influence a jury in virtue of the fact that they appear easy to understand. By appearing visually simple, even though they are really statistically constructed maps with a host of assumptions built into them, a lay jury or a judge might take brain scans to be more reliable or relevant than they actually are. Should courts exclude brain scans for being more prejudicial than probative? Herein, we rehearse a brief history of brain scans admitted into criminal trials in the United States, then describe the results of a recent analysis of appellate court decisions that referenced 1 or more brain scans in the judicial decision. In particular, we aim to explain how courts use neuroscience imaging data: Do they interpret the data correctly? Does it seem that scans play an oversized role in judicial decision-making? And have they changed how criminal defendants are judged? It is our hope that in answering these questions, clinicians and defence attorneys will be able to make better informed decisions regarding about how to manage those incarcerated.

Unable or Unwilling to Exercise Self-control? The Impact of Neuroscience on Perceptions of Impulsive Offenders

In growing numbers of court cases, neuroscience is presented to document the mental state of the offender at the level of the brain. While a small body of research has documented the effects of describing the brain state of psychotic offenders, this study tested the impact of neuroscience that could apply to far more offenders; that is the neuroscience of impulse control. In this online vignette experiment, 759 participants sentenced a normally controlled or normally impulsive actor, who committed a violent offense on impulse, explained in either cognitive or neurobiological terms. Although participants considered the neurobiological actor less responsible for his impulsive disposition than the cognitive actor, the neuroscientific testimony did not affect attributions of choice, blame, dangerousness, or punishment for the criminal act. In fact, the neuroscientific testimony exacerbated the perception that the offender offended consciously and “really wanted” to offend. The described disposition of the actor was also influential: participants attributed more capacity for reform, more free choice and consequently, more blame to the normally controlled actor. Participants also attributed this actor's offending more to his social life experiences and less to his genes and brain. However, this shift in attributions was unable to explain the greater blame directed at this offender. Together, such findings suggest that even when neuroscience changes attributions for impulsive character, attributions for impulsive offending may remain unchanged. Hence this study casts doubt on the mitigating and aggravating potential of neuroscientific testimony in court.

Don't Ask a Neuroscientist about Phases of the Moon

Ongoing developments in neuroscientific techniques and technologies-such as neuroimaging-offer potential for greater insight into human behavior and have fostered temptation to use these approaches in legal contexts. Neuroscientists are increasingly called on to provide expert testimony, interpret brain images, and thereby inform judges and juries who are tasked with determining the guilt or innocence of an individual. In this essay, we draw attention to the actual capabilities and limitations of currently available assessment neurotechnologies and examine whether neuroscientific evidence presents unique challenges to existing frameworks of evidence law. In particular, we focus on (1) fundamental questions of relevance and admissibility that can and should be posed before the tests afforded in Daubert v. Merrill Dow Pharmaceuticals or Frye v. U.S. are applied and (2) how these considerations fit into the broader contexts of criminal law. We contend that neuroscientific evidence must first be scrutinized more heavily for its relevance, within Daubert and Federal Rule of Evidence 702, to ensure that the right questions are asked of neuroscientists, so as to enable expert interpretation of neuroscientific evidence within the limits of their knowledge and discipline that allows the judge or jury to determine the facts at issue in the case. We use the analogy provided by the Daubert court of an expert on the phases of the moon testifying to an individual's behavior on a particular night to ensure that we are, in fact, asking the neuroscientific expert the appropriate question.

Free Will and the Brain Disease Model of Addiction: The Not So Seductive Allure of Neuroscience and Its Modest Impact on the Attribution of Free Will to People with an Addiction

Free will has been the object of debate in the context of addiction given that addiction could compromise an individual's ability to choose freely between alternative courses of action. Proponents of the brain-disease model of addiction have argued that a neuroscience perspective on addiction reduces the attribution of free will because it relocates the cause of the disorder to the brain rather than to the person, thereby diminishing the blame attributed to the person with an addiction. Others have worried that such displacement of free will attribution would make the person with a drug addiction less responsible. Using the paradigmatic literature on the seductive allure of neuroscience explanations, we tested whether neuroscience information diminishes attributions of free will in the context of addiction and whether respondent characteristics influence these attributions and modulate the effect of neuroscience information. We performed a large-scale, web-based experiment with 2,378 German participants to explore how attributions of free will in the context of addiction to either alcohol or cocaine are affected by: (1) a text with a neurobiological explanation of addiction, (2) a neuroimage showing effects of addiction on the brain, and (3) a combination of a text and a neuroimage, in comparison to a control group that received no information. Belief in free will was measured using the FAD-Plus scale and was, subsequent to factor analysis, separated into two factors: responsibility and volition. The investigated respondent characteristics included gender, age, education, self-reported knowledge of neuroscience, substance-use disorder (SUD), and having a friend with SUD. We found that attributions of volition (in the cocaine-subsample) were reduced in the text and neuroimage-treatment compared to the control group. However, respondent characteristics such as education and self-reported knowledge of neuroscience were associated with lower attributions of responsibility for both substances, and education was associated with lower attribution of volition for the alcohol sub-sample. Interaction analyses showed that knowledge of neuroscience was found to generally decrease attribution of responsibility. Further research on attribution of free will should consider the effects of context and respondent characteristics, which appeared surprisingly larger than those induced by experimental treatments.

Communicating the Neuroscience of Psychopathy and Its Influence on Moral Behavior: Protocol of Two Experimental Studies

Neuroscience has identified brain structures and functions that correlate with psychopathic tendencies. Since psychopathic traits can be traced back to physical neural attributes, it has been argued that psychopaths are not truly responsible for their actions and therefore should not be blamed for their psychopathic behaviors. This experimental research aims to evaluate what effect communicating this theory of psychopathy has on the moral behavior of lay people. If psychopathy is blamed on the brain, people may feel less morally responsible for their own psychopathic tendencies and therefore may be more likely to display those tendencies. An online study will provide participants with false feedback about their psychopathic traits supposedly based on their digital footprint (i.e., Facebook likes), thus classifying them as having either above-average or below-average psychopathic traits and describing psychopathy in cognitive or neurobiological terms. This particular study will assess the extent to which lay people are influenced by feedback regarding their psychopathic traits, and how this might affect their moral behavior in online tasks. Public recognition of these potential negative consequences of neuroscience communication will also be assessed. A field study using the lost letter technique will be conducted to examine lay people's endorsement of neurobiological, as compared to cognitive, explanations of criminal behavior. This field and online experimental research could inform the future communication of neuroscience to the public in a way that is sensitive to the potential negative consequences of communicating such science. In particular, this research may have implications for the future means by which neurobiological predictors of offending can be safely communicated to offenders.

Making sense of research on the neuroimage bias

Both academic and legal communities have cautioned that laypersons may be unduly persuaded by images of the brain and may fail to interpret them appropriately. While early studies confirmed this concern, a second wave of research was repeatedly unable to find evidence of such a bias. The newest wave of studies paints a more nuanced picture in which, under certain circumstances, a neuroimage bias reemerges. To help make sense of this discordant body of research, we highlight the contextual significance of understanding how laypersons' decision making is or is not impacted by neuroimages, provide an overview of findings from all sides of the neuroimage bias question, and discuss what these findings mean to public use and understanding of neuroimages.

The selective allure of neuroscientific explanations

Some claim that recent advances in neuroscience will revolutionize the way we think about human nature and legal culpability. Empirical support for this proposition is mixed. Two highly-cited empirical studies found that irrelevant neuroscientific explanations and neuroimages were highly persuasive to laypersons. However, attempts to replicate these effects have largely been unsuccessful. Two separate experiments tested the hypothesis that neuroscience is susceptible to motivated reasoning, which refers to the tendency to selectively credit or discredit information in a manner that reinforces preexisting beliefs. Participants read a newspaper article about a cutting-edge neuroscience study. Consistent with the hypothesis, participants deemed the hypothetical study sound and the neuroscience persuasive when the outcome of the study was congruent with their prior beliefs, but gave the identical study and neuroscience negative evaluations when it frustrated their beliefs. Neuroscience, it appears, is subject to the same sort of cognitive dynamics as other types of scientific evidence. These findings qualify claims that neuroscience will play a qualitatively different role in the way in which it shapes people’s beliefs and informs issues of social policy.

On the (non) persuasive power of a brain image

The persuasive power of brain images has captivated scholars in many disciplines. Like others, we too were intrigued by the finding that a brain image makes accompanying information more credible (McCabe & Castel in Cognition 107:343-352, 2008). But when our attempts to build on this effect failed, we instead ran a series of systematic replications of the original study-comprising 10 experiments and nearly 2,000 subjects. When we combined the original data with ours in a meta-analysis, we arrived at a more precise estimate of the effect, determining that a brain image exerted little to no influence. The persistent meme of the influential brain image should be viewed with a critical eye.

Neurologic disorder and criminal responsibility

Sufferers from neurologic and psychiatric disorders are not uncommonly defendants in criminal trials. This chapter surveys a variety of different ways in which neurologic disorder bears on criminal responsibility. It discusses the way in which a neurologic disorder might bear on the questions of whether or not the defendant acted voluntarily; whether or not he or she was in the mental state that is required for guilt for the crime; and whether or not he or she is deserving of an insanity defense. The discussion demonstrates that a just determination of whether a sufferer from a neurologic disorder is diminished in his or her criminal responsibility for harmful conduct requires equal appreciation of the nature of the relevant disorder and its impact on behavior, on the one hand, and of the legal import of facts about the psychologic mechanisms through which behavior is generated, on the other.

Brain trauma, PET scans and forensic complexity

Positron Emission Tomography (PET) is a medical imaging technique that can be used to show brain function. Courts have admitted PET scan evidence in cases involving brain damage, injury, toxic exposure, or illness ("brain trauma") and to support claims of diminished cognitive abilities and impulse control. Despite the limited data on the relationships between PET, brain trauma and behavior, many courts admit PET scan evidence without much critical analysis. This article examines the use of PET as proof of functional impairment and justification of abnormal behavior by explaining its diagnostic use and limitations, the limited support for claims of its relationship to behavior, and evidentiary considerations that should govern its admission into court as evidence. The authors urge courts to consider PET evidence, claims of experts, and the scope of the proposed testimony with greater deference to the clinical scope of PET, as outlined by the American College of Radiology's appropriateness criteria and the Working Group Report of the American Psychiatric Association.

Visual attention and the neuroimage bias

Several highly-cited experiments have presented evidence suggesting that neuroimages may unduly bias laypeople’s judgments of scientific research. This finding has been especially worrisome to the legal community in which neuroimage techniques may be used to produce evidence of a person’s mental state. However, a more recent body of work that has looked directly at the independent impact of neuroimages on layperson decision-making (both in legal and more general arenas), and has failed to find evidence of bias. To help resolve these conflicting findings, this research uses eye tracking technology to provide a measure of attention to different visual representations of neuroscientific data. Finding an effect of neuroimages on the distribution of attention would provide a potential mechanism for the influence of neuroimages on higher-level decisions. In the present experiment, a sample of laypeople viewed a vignette that briefly described a court case in which the defendant’s actions might have been explained by a neurological defect. Accompanying these vignettes was either an MRI image of the defendant’s brain, or a bar graph depicting levels of brain activity–two competing visualizations that have been the focus of much of the previous research on the neuroimage bias. We found that, while laypeople differentially attended to neuroimagery relative to the bar graph, this did not translate into differential judgments in a way that would support the idea of a neuroimage bias.

Neuroscientists in court

Neuroscientific evidence is increasingly being offered in court cases. Consequently, the legal system needs neuroscientists to act as expert witnesses who can explain the limitations and interpretations of neuroscientific findings so that judges and jurors can make informed and appropriate inferences. The growing role of neuroscientists in court means that neuroscientists should be aware of important differences between the scientific and legal fields, and, especially, how scientific facts can be easily misunderstood by non-scientists, including judges and jurors.

Look Again: Effects of Brain Images and Mind–Brain Dualism on Lay Evaluations of Research

Brain scans have frequently been credited with uniquely seductive and persuasive qualities, leading to claims that fMRI research receives a disproportionate share of public attention and funding. It has been suggested that functional brain images are fascinating because they contradict dualist beliefs regarding the relationship between the body and the mind. Although previous research has indicated that brain images can increase judgments of an article's scientific reasoning, the hypotheses that brain scans make research appear more interesting, surprising, or worthy of funding have not been tested. Neither has the relation between the allure of brain imaging and dualism. In the following three studies, laypersons rated both fictional research descriptions and real science news articles accompanied by brain scans, bar charts, or photographs. Across 988 participants, we found little evidence of neuroimaging's seductive allure or of its relation to self-professed dualistic beliefs. These results, taken together with other recent null findings, suggest that brain images are less powerful than has been argued.

Neuroimages in court: less biasing than feared

Neuroscience is increasingly poised to play a role in legal proceedings. One persistent concern, however, is the intuition that brain images may bias, mislead, or confuse jurors. Initially, empirical research seemed to support this intuition. New findings contradict those expectations, prompting a rethinking of the 'threat' of neuroscience in the courtroom.

Are there lessons to be learned from a more scientific approach to mental condition defences?

The timing of the English Law Commission's consideration of reform to the law of insanity coincides with increasing scientific and in particular neuroscientific understanding of the brain. The work of researchers is leading to a greater comprehension of what had been termed irresistible impulses to commit crime and of the impact of brain damage, particularly evidence of brain lesions and frontal lobe damage on behaviour. There remain problems in establishing causal relationships which might diminish or eliminate criminal responsibility for crimes committed by those suffering from pre existing mental conditions at the time they commit a criminal offence. This is especially the case where those mental conditions are of short duration. However, the law should not ignore the best available scientific knowledge. Neuroscientific advances are already informing court deliberations in England and Wales: assisting in considerations of guilt, fitness to plead and in sentencing. In terms of the insanity defence the questions that the law seeks to address are not necessarily the most medically or scientifically pertinent questions. They remain grounded in 19th century scientific understanding. It is argued that the more nuanced Dutch approach to mental condition defences warrants very serious consideration by those charged with making proposals to reform the English law.