Homicide offenders have less pronounced psychopathy, sadism, and criminal recidivism compared to other violent offenders and non-violent offenders

How dark is the personality of murderers? Psychopathy, Machiavellianism, and sadism in homicide offenders. Janko Međedović, Nikola Vujičić. Personality and Individual Differences, Volume 197, October 2022, 111772. https://doi.org/10.1016/j.paid.2022.111772

Abstract: Dark personality traits describe amoral and antisocial behavioral dispositions and are often described by psychopathy (i.e., interpersonal, affective, lifestyle, and antisocial characteristics), narcissism, Machiavellianism, and sadism. These traits are related to various socially detrimental behavioral outcomes, including criminal behavior and delinquency. Furthermore, psychopathy is frequently related to homicide, both in scientific and in popular literature; however, the empirical data on the link between psychopathy and other dark traits with homicide is still scarce. We examined self-reported psychopathy, Machiavellianism, sadism, and the indicators of criminal recidivism (number of offences, number of lawful sentences and penal recidivism) in a sample of male homicide offenders (N = 46), other violent offenders (N = 82), and non-violent offenders (N = 119). The results showed that homicide offenders have less pronounced psychopathy, sadism, and criminal recidivism compared to the other two groups – the differences were particularly evident in comparison to the group of non-homicide violent offenders. There were no statistically significant differences in Machiavellianism. Our data cast a doubt on the widely acknowledged link between psychopathy and murder. The findings can be explained largely by the fact that homicide is a heterogeneous criminal offence; while it is possible that psychopathy and other dark traits may be linked to some types of homicide, this link cannot be established for homicide in general.

Introduction

In recent decades, there has been a growing interest in personality dispositions toward amoral and antisocial behavior. A comprehensive model of these traits is labeled as the Dark Tetrad (Međedović & Petrović, 2015; Paulhus, 2014) and encompasses traits like narcissism, Machiavellianism, psychopathy and sadism. Narcissism depicts entitlement, superiority and an inflated view of self (Raskin & Terry, 1988); Machiavellianism represents an attitude which rationalizes and justifies the use of other people for one's self interest (Christie & Geis, 1970), while sadism is based on the aberration in emotional processes where one feels positive emotions (enjoyment) when hurting others or watching others in distress (O'Meara et al., 2011). The trait that has the longest history of scientific inquiry is psychopathy – it represents a behavioral syndrome itself that consists of several narrow traits. There are various models of psychopathy, one of the most prominent is proposed by Hare and collaborators and it defines psychopathy as a syndrome of interpersonal (egoistic and manipulative) behavior, affective characteristics (lack of emotional empathy, fear, and guilt), lifestyle characteristics (impulsiveness, lack of long-term plans, sensation seeking) and antisocial behavior (Hare & Neumann, 2008). The dark personality traits are related to various socially undesirable outcomes like cheating (Esteves et al., 2021), bullying (van Geel et al., 2017), violence (Pailing et al., 2014), and others.

Since the Dark tetrad traits are based on selfishness, lack of compassion, and the tendency to manipulate or hurt others, it is not surprising that they are important predictors of antisocial behavior and delinquency (Chabrol et al., 2009; Međedović & Kovačević, 2020). The relation between dark traits and criminal behavior is mostly researched in the context of psychopathy and it is most firmly established for this trait. Psychopathy is positively related to the number of violent and-nonviolent offences, substance abuse, contact with police and criminal courts, and others (Vaughn & DeLisi, 2008). It is negatively associated with educational levels, long-term jobs, the age of the first offence and first lawful sentence (Žukauskienė et al., 2010). Finally, there is reliable data that psychopathy can positively predict criminal recidivism (Leistico et al., 2008; Međedović et al., 2012a, Međedović et al., 2012b; Salekin, 2008). Due to the fact that recidivists commit most criminal offences (e.g., Someda, 2009), this association has both scientific and practical implications.

Comprehensive taxonomies of the dark traits, including the Dark tetrad, have rarely been examined in a criminological, penal, or forensic context; hence, the research on the links between the dark traits and the type of criminal offence is still very scarce. However, there is a common belief that psychopathy is related to homicide offences, both in popular culture and media (Lilienfeld & Arkowitz, 2007) and in scientific context (Fox & DeLisi, 2019). Indeed, there is a large amount of data showing that murders committed by psychopathic individuals have some specific characteristics. For example, homicides perpetrated by individuals with elevated psychopathy are more instrumental in nature (i.e., premeditated and planned), deliberate, and to a lower level motivated by affective reactions (Woodworth & Porter, 2002). Furthermore, the data show that psychopathic murderers are more frequently not close to their victim and deny their charges (Häkkänen-Nyholm & Hare, 2009). The existing data suggests that a positive link between psychopathy and reoffending exists in homicide perpetrators as well (Laurell & Dåderman, 2005). Finally, psychopathy is more pronounced in the group of offenders who have committed sexual homicides (Porter et al., 2003) and it is positively related to the criminal relapse in this group of offenders (Myers et al., 2010).

Therefore, it seems that homicide offences committed by psychopathic individuals have some specific qualities. However, is there a connection between psychopathy and murder in general - are individuals with elevated psychopathy traits more prone to commit homicide than other types of offences? The existing evidence suggests that the answer is once again positive. A recent meta-analysis showed large effect sizes of the link between psychopathy and homicide (Fox & DeLisi, 2019). However, the data is not unambiguous. There are studies that have found that psychopathy traits (i.e., lifestyle and interpersonal characteristics) are expressed to a lower extent in a group of homicide offenders compared to non-homicide repeated offenders (Sherretts et al., 2017); there were no differences between murderers and first-time non-homicide offenders in this study. The authors concluded that psychopathic traits are more likely to be found in persistent offenders (i.e., recidivists), characterized by criminal careers, than in homicide offenders.

Current empirical literature on the links between the dark traits (all but psychopathy) and homicide is quite scarce. This is in contrast with the high heuristic and practical importance of the topic: by establishing these links, personality psychologists can achieve a more in-depth understanding of the dark side of the human personality; on the other hand, forensic practitioners can achieve better understanding of the murderers' personality and provide more accurate models for predicting homicide offences. The goal of the present research is to provide a more detailed examination of the relation between the dark personality characteristics and homicide. We believe that there are three main contributions of the present study over the existing ones. Firstly, we analyzed not only psychopathy, but also Machiavellianism and sadism in homicide offenders (Narcissism unfortunately was not included in the list of variables collected in this study); the data on the two latter traits in this context are very scarce. Sadism may be especially significant in the context of homicide offences: murders are violent offences and sadism represents particularly volatile and destructive form of aggressiveness – the one which carries positive emotions as a reinforcement for the perpetrator (Međedović, 2017). Hence, it can be assumed that sadism may be relevant in understanding personality characteristics of homicide offenders. Secondly, we compared not only homicide to non-homicide offenders in this study. Homicide is just one of the violent offences, however, it may differ from other forms of violent offences; therefore, we analyzed homicide offenders, non-homicide violent offenders and non-violent offenders. Finally, we included the measures of criminal recidivism in the study.

Our analyses were guided by several hypotheses. Note that we base our hypotheses on previous research on psychopathy in a forensic and criminological context since there are no data regarding other traits. However, we believe that the same hypotheses can be set for all examined dark traits in the context of the present research (i.e., examining the relations between dark traits, the type of offence and criminal recidivism): psychopathy (especially multidimensionally-measured psychopathy as it was assessed in the present study) shares a substantial portion of variation with other dark traits (Chabrol et al., 2009; Međedović & Petrović, 2015), and this shared variation is based on the lack of empathy and interpersonal antagonism (Dinić et al., 2021). Therefore, we expected all the dark traits to be positively related to criminal recidivism. Regarding the relation between the dark traits and homicide, two contrasting hypotheses can be made: leaning on meta-analytic results (Fox & DeLisi, 2019) we could expect that psychopathy is more highly pronounced in homicide offenders than the other two groups. On the contrary, the results of Sherretts et al. (2017) suggest that the dark traits may be less expressed in the homicide offenders compared to other groups of offenders.