Juror decision making in not criminally responsible on account of mental disorder trials: Effects of defendant gender and mental illness type

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Abstract

This study sought to examine the potential impact of defendant gender and mental illness type on Canadian juror decision making by manipulating the gender (man, woman) and mental illness (substance abuse disorder, schizophrenia, bipolar, depression) of the defendant in a second-degree murder case involving an insanity plea. Participants read a trial transcript that included definitions of second-degree murder and the not criminally on account of mental disorder (NCRMD) defense. Participants then provided a verdict (guilty or NCRMD) and completed various scales measuring attributional judgments, perceptions of the defendant, and perceived dangerousness. Contrary to expectations, NCRMD was chosen over a guilty verdict in the majority of cases. Findings also indicated that participant decisions and perceptions regarding defendants diagnosed with substance abuse disorder differed from the other mental illness groups. The gender of the defendant had an influence on participants' perceptions of internal attributions, and the perceived stability of criminal behaviors. Results suggest that perceptions of mental illness influence verdicts in NCRMD cases, and that defendant gender plays a role in participants' perceptions of defendants. These findings contribute to the scarce literature on mental illness in the Canadian court system. Future research should examine the interaction between juror gender, defendant gender, and mental illness in insanity cases.

Introduction

There is an anticipated stigma and discrimination attached to mental illness (e.g., perceived dangerousness and associated desire for social distance; Martin, Pescosolido, & Tuch, 2000). Unfortunately, the media tends to sensationalize rare, tragic events associated with someone having a mental disorder, which reinforces “dangerous” stereotypes related to mental illness and amplifies the public's fear toward persons with mental illness (Angermeyer et al., 1998, Phelan and Link, 2004) and toward the insanity defense (Kobau, DiIorio, Chapman, & Delvecchio, 2010). As a result, public perceptions of mentally ill persons as criminally dangerous continue to be greatly exaggerated despite an apparent improvement in understanding mental illness, and in light of findings repeatedly demonstrating that mental illness is not a major contributor to criminal violence (Markowitz, 2011, Stuart and Arboleda-Flórez, 2001). It is therefore worthwhile to conduct research on perceptions toward mental illness, particularly at a time when the number of people with mental illness in Canadian prisons is higher than ever.

While much research has examined attitudes toward the insanity defense, perceptions of mental illnesses, and jury decision making independently, little research has explored these areas in conjunction with one another. In addition, there is limited literature regarding gender differences among mentally ill defendants and jurors' perceptions of these gender differences. Given that juror decisions and perceptions of mental illness and gender are inextricably linked in insanity cases, the aim of the current study was to further explore these factors in relation to each other.

The insanity defense, referred to as the Not Criminally Responsible on Account of Mental Disorder (NCRMD) defense in Canada, is appropriately used when a mental disorder rendered the person incapable of appreciating the nature and quality of the act or of knowing that it was wrong. Literature regarding the insanity defense provides evidence of negative attitudes toward both the defense itself (Bloechl et al., 2007, Hans, 1986, Maeder et al., 2015, Skeem et al., 2004) and toward the individuals who are acquitted on the basis on their mental disorder (Bloechl et al., 2007). Perceptions and attitudes are largely driven by myths and common inaccuracies about the defense, including the notion that the insanity defense is overused, that it is a “loophole,” and that most accused who claim insanity are freely released into the community (Hans, 1986, Skeem et al., 2004). Contrary to public perception, the insanity defense is actually only attempted in less than 1% of all arrests, is unsuccessful in approximately 75% of cases (Perlin, 1996), and has recently been found to represent less than 1% of adult criminal court cases processed annually in Canada (Miladinovic & Lukassen, 2014).

The relevance of the insanity defense for various mental illnesses is sometimes questioned by the public. Jeffrey, Pasewark, and Bieber (1988) examined 133 male defendants entering insanity pleas and aimed to predict successful adjudications of these cases. The defendants were evaluated for insanity from July 1, 1980, to June 30, 1983. Of the 133 defendants, 36 (27%) were adjudicated Not Guilty by Reason of Insanity and 97 (73%) were convicted. The primary diagnoses accorded to defendants at time of psychiatric evaluation were substance abuse disorders (27%), schizophrenic disorders (24%), antisocial personality disorder (1 2%), other personality disorders (8%), major affective disorders (8%), psychosexual disorders (5%), mild mental retardation (3%), and organic mental disorders (5%). Findings from this study revealed that a diagnosis of schizophrenia was most positively related to insanity adjudication, whereas diagnoses of substance abuse and personality disorders were negatively related to the insanity verdict. Recent research from Justice Canada has found that the majority of NCRMD individuals accused of serious violent offenses had a diagnosis in the psychosis spectrum (Crocker, Seto, Nicholls, & Coté, 2013). For 37.8% of NCRMD individuals, this was the only diagnosis, while for 68.9%, this diagnosis was present either on its own or concurrently with another diagnosis. A diagnosis of substance abuse, on its own or often concurrently, accounted for 27.9%, while personality disorder and mood disorder diagnoses accounted for 21% and 23.6%, respectively (Crocker et al., 2013). While the decisions found in the study by Jeffrey et al. (1988) are somewhat reflective of the NCRMD landscape in Canada, it also highlights how perceptions of mental illness can influence verdicts in insanity cases.

In jury decision making, a poor understanding of the nature of the defense creates a risk of biasing verdicts. Recent research by Maeder et al. (2015) attempted to address biased attitudes by correcting inaccuracies via education about the insanity defense. Participants in this study were given an education sheet prior to reading a case vignette, providing a verdict, and completing an NCRMD Attitudes scale. Participants randomly assigned to the experimental condition read information about the NCRMD defense (i.e., the legal definition of an individual who can be found NCRMD, the percentage of Canadian criminals who are deemed NCRMD, and the disposition options for those who are found NCRMD). They found that while education can improve attitudes, it does not translate to less biased verdict decisions. These findings suggest that it is not only misinformation about the NCRMD defense that is responsible for verdict decisions and that perhaps overarching attitudes and perceptions about mental illness are at play.

Perceptions of mental illness, and in particular schizophrenia, stem largely from media sources, such as television shows, movies, and the news (Angermeyer et al., 2005, Bergman et al., 2000, Knifton and Quinn, 2008). The media portrayals of mental illness are largely pejorative, portraying these individuals in a negative light and sensationalizing rare and tragic violent acts (Dietrich et al., 2006, Wilson et al., 1999). It is not surprising, then, that the belief that individuals with a mental illness are dangerous is one of the most common and persistent misconceptions among the general public (Arboleda-Flórez, 2003, Pescosolido et al., 1999). This belief has been further evidenced in experimental studies. For example, Silton, Flannelly, Milstein, and Vaaler (2011) examined stigma in the United States from 1996 to 2006, specifically exploring perceptions of mental illness and dangerousness. Participants in this study were presented with one of four vignettes that described the behavior of a person who met the criteria for the “presenting problems” of alcohol dependence, depression, schizophrenia, or minor problems, and were then asked a series of questions about the character depicted in the profile. Findings from this research indicated that participants perceived vignette characters presenting with schizophrenia as the most likely character to have a mental illness. They also found that participants had a greater desire for social distance for both alcoholism and schizophrenia and found that part of this desire was attributable to perceptions of dangerousness for these groups. Similarly, a review of 62 population studies using case vignettes (see Angermeyer & Dietrich, 2006) found that, in general, members of the lay public cannot correctly recognize mental disorders. Specifically, schizophrenic symptoms are considered to be signs of mental illness (range 69–88%) more often than are symptoms of depression (26–69%) or of alcoholism (16–49%). This review further found that individuals who spontaneously labeled vignette characters as mentally ill were more likely to describe the characters as dangerous and unpredictable.

The perceived link between mental illness and dangerousness has been debated in the literature. While some studies have shown a general association between substance abuse, crime, and violence (e.g.Boden et al., 2012, Popovici et al., 2012), these do not paint the full picture. For example, Angermeyer (2000) asserts that an extremely small proportion of violent crimes are actually committed by the severely mentally ill and that the risk of being randomly and violently attacked by an individual with schizophrenia is lower than the risk of being attacked by offenders free of mental illnesses. Similarly, findings from research by Stuart and Arboleda-Flórez (2001) examining the prevalence of mental illness in a sample of remanded offenders in Western Canada suggest that individuals with mental and substance abuse disorders are not major contributors to police-identified criminal violence. While results from this study showed a relatively high prevalence rate for mental illness (up to 61%), the calculated proportion of violent offences that could be attributed to offenders with mental illness was low (3% for non-substance-use disorders, and an additional 7% for substance-use disorders). Public perceptions of mentally ill persons as criminally dangerous may therefore be exaggerated, and so regardless of the exact prevalence rates of violence for these groups, differences in perceptions of different mental disorders are worthy of further investigation.

It was thought that negative attitudes toward mental illness were related to the public's limited understanding of, and knowledge about, mental illness. As a result, efforts have been made to educate and promote public awareness of mental illness. Schomerus et al. (2012) sought to assess the evolution of public attitudes about mental illness through systematic and meta-analytic reviews. Findings from their research suggest that mental health literacy has improved and that there is a greater acceptance of seeking professional help for mental health problems. That being said, Schomerus and colleagues also found that these changes did not result in remedying negative attitudes toward mental illness. Specifically, they concluded that the negative stereotypes and social rejection of individuals with mental illness have not diminished as hoped and instead have remained “disturbingly” stable over the last 20 years. Given this conclusion, it is worthy to explore the role of juror perceptions of mental illness in insanity case decisions.

Perceptions of women tend to include stereotypes such as warm, kind, and emotional, whereas men are perceived to be strong, assertive, and aggressive (Prentice and Carranza, 2002, Williams and Best, 1990). In terms of gender and perceived dangerousness, women tend to be perceived as significantly less likely to be dangerous than male characters (Silton et al., 2011). In addition to these gender stereotypes, there are also stereotypes regarding gender and mental illness. Like the development of many other stereotypes, these involve a combination of knowledge, beliefs, and expectations (Hamilton and Rose, 1980, Risen et al., 2007, Tversky and Kahneman, 1974). Specifically, different mental illnesses are more prevalent among, and are also more likely to be associated with, a particular gender group (e.g., depression = female, substance abuse = male; Affi, 2007, Wirth and Bodenhausen, 2009, World Health Organization, 2016, Zonana et al., 1990). In terms of the insanity defense, Dirks-Linhorst (2014) examined 30 years of insanity acquittals. In this sample, the primary diagnoses of insanity acquittees were schizophrenia (55%), bipolar disorder (15.1%), and mental retardation (11.9%), with secondary diagnoses of substance use or abuse disorders (56.6%), personality disorders (44.8%), and borderline intellectual functioning (11.9%). Consistent with the literature cited above, results from this study found that female defendants were more likely to have been diagnosed with major depression and less likely to have a substance abuse diagnosis, compared to male counterparts.

Wirth and Bodenhausen (2009) investigated the role played by gender in moderating mental-illness stigma. In this study, participants read a case summary of a person experiencing a mental illness, whereby cases were manipulated to reflect either a male-typical disorder (i.e., alcoholism) or a female-typical disorder (i.e., depression). Participants subsequently completed a range of rating scales designed to assess stigmatization of the target. Wirth and Bodenhausen (2009) interestingly found that when cases were gender stereotype consistent (i.e., male alcoholism and female depression), respondents felt more negative affect, less sympathy, and less inclination to help, compared to when cases were gender stereotype inconsistent (i.e., female alcoholism and male depression). The authors suggest that this pattern could be explained by the fact that gender-typical cases were also found to be significantly less likely to be seen as genuine mental disturbances. Gender-stereotype-consistent mental illness symptoms may therefore lend themselves readily to blaming the individual for more extreme forms of “typical” behavior. The patterns associated with gender stereotype consistency in mental illness presumably imply more personal responsibility and consequently become a relevant factor in mental-illness stigma (Wirth & Bodenhausen, 2009).

Breheney, Groscup, and Galietta (2007) conducted one of the few studies of which we are aware that examined defendant gender and juror decisions in insanity cases. Contrary to expectations, their findings revealed that female defendants were found guilty more often than their male counterparts and that women were also deemed to be more responsible for their crimes, to have known what they were doing, and to have planned the crime more so than men. Breheney and colleagues suggest that this may indicate a bias against female defendants in insanity cases. In contrast to the work by Wirth and Bodenhausen (2009) described above, the findings by Breheney and colleagues may speak to perceived gender stereotype inconsistency, whereby females are often thought to be gentle and not typically dangerous, and participants may therefore punish gender deviance (e.g., Costrich, Feinstein, Kidder, Marecek, & Pascale, 1975). Specifically, if a woman did commit the act in question [which is not disputed in insanity cases], then this characteristic of criminality, combined with mental illness, would not fit femininity-stereotypes—therefore she may be more likely to be perceived as blameworthy compared to male counterparts (Maeder & Dempsey, 2013). In other words, since aggression and violence are stereotypically associated with men (Huddy & Terkildsen, 1993), it may be that female defendants may be viewed as behaving in a gender-stereotype-inconsistent way (Gilbert, 2002), which may itself be a source of stigmatization, and backlash may ensue (Rudman & Fairchild, 2004) in the form of guilty verdicts (Dean et al., 2000, Forsterlee et al., 2004). This is consistent with other research outside of the context of mental illness that has found that deviating from gender stereotypes may have detrimental effects for defendants (e.g., Wayne, Riordan, & Thomas, 2001). However, it is inconsistent with the crime-congruency literature. Specifically, crime-congruency effects have been explored in relation to race and suggest that when a defendant's race is congruent with the crime stereotype (e.g., black defendant charged with auto theft) compared to non-congruent (e.g., black defendant charged with embezzlement), verdicts and attributions tend to be more negative, a more limited information search is conducted, and more confirmatory evidence is sought (Jones & Kaplan, 2003). In the context of gender, crime congruency would exist when the defendant's gender is congruent with stereotypes (e.g., male with substance abuse diagnosis in insanity case). The findings by Breheney and colleagues contrast with those by Wirth and Bodenhausen described above and with the idea of gender–crime congruency effects. It appears then that the influence of gender-based stereotype consistency may depend on the circumstances of the individual and the context of his or her behavior. This is therefore an area that requires further exploration in the context of insanity cases, and the interacting effects of defendant gender and mental illness on juror decision making.

Section snippets

Current study

While previous research examining gender in the courtroom and juror decisions (e.g., gender-domain congruency of expert witnesses; McKimmie et al., 2004, Schuller et al., 2001; and gender stereotype consistency; Maeder & Dempsey, 2013) has provided some evidence to suggest that mock jurors may rely on gender stereotypes when making trial decisions, there remains a gap in the literature regarding the examination of defendant gender and juror decisions in insanity cases. The study materials used

Discussion

This research contributes to the scarce literature on juror decisions and perceptions of mental illness in NCRMD cases in Canada. While past literature and media reports suggest that the public may not support the idea of NCRMD (Bloechl et al., 2007, Hans, 1986, Maeder et al., 2015, Skeem et al., 2004), findings from this study diverged from this. Specifically, while participants in this study were harsher toward the defendant with substance abuse disorder, they were overall more willing to

Conclusion

This study was designed to extend the limited literature examining the influence of defendant gender in NCRMD cases in Canada. Unlike the persisting negative attitudes toward the insanity defense demonstrated by earlier research, our findings reveal that participants are largely willing to give a verdict of NCRMD to defendants with different mental illness types (with the exception of substance abuse). While the gender of the defendant did not influence verdict decisions, defendants' behaviors

Acknowledgments

We would like to recognize and thank Laura McManus, who assisted with participant recruitment and data collection for this study.

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