Of all the dark personality traits, this one shows the strongest link to crime

New research is shedding light on how certain personality traits may influence criminality. In a study published in Current Psychology, Machiavellianism—a trait characterized by manipulative and deceitful behavior—emerged as the strongest predictor of repeated criminal activity. This trait, along other Dark Tetrad personality traits such as psychopathy, narcissism, and sadism, could help explain why some individuals are more likely to reoffend.

The Dark Tetrad is a group of four personality traits—Machiavellianism, psychopathy, narcissism, and sadism—known for their links to malevolent and antisocial behaviors. People with these traits tend to manipulate, deceive, or harm others, show emotional coldness, or have an inflated sense of self-importance.

Machiavellianism involves manipulation and strategic thinking for personal gain, while psychopathy is characterized by a lack of empathy and impulsive behavior. Narcissism focuses on excessive self-regard and entitlement, and sadism includes deriving pleasure from others’ suffering. These traits have been widely studied in psychology for their connections to antagonistic behaviors, but researchers wanted to see how they individually relate to criminal activity.

Previous studies mostly examined these traits collectively or within non-criminal populations, limiting insights into how each trait might distinctly influence crime. The new study specifically looked at a sample of incarcerated individuals to better capture these dark traits in people with a history of criminal activity, potentially enhancing risk assessments and rehabilitation strategies.

“There is a large amount of empirical data that show the importance of personality traits in explaining criminal behavior, delinquency, and antisocial behavior,” said study author Janko Međedović, a researcher at the Institute of Criminological and Sociological Research in Belgrade and author of Evolutionary Behavioral Ecology and Psychopathy.

“The most of the research in this field was focused on trait psychopathy, which indeed turned out to be a robust predictor of criminal behavior and criminal recidivism. However, the Dark Tetrad taxonomy has a heuristic potential to even more precisely and detaily describe the personality characteristics associated with amoral and antisocial behavior.”

“Curiously, the empirical research that examines the associations between the Dark Tetrad traits and criminality in the samples of lawfully convicted individuals is still relatively scarce. This was our motivation for the current study – to empirically evaluate the explanatory potentials of Dark Tetrad traits in predicting criminal behavior as a highly socially-relevant aspect of human functioning due to its socially-detrimental outcomes.”

The study involved 471 prisoners in Serbia, predominantly men with an average age of around 40. Participants were selected from five major prisons and represented a variety of educational backgrounds, though most had completed only high school or lower levels of education. This study took place with the consent of the participants, who completed questionnaires in supervised settings.

To measure the four dark personality traits, the researchers used the “Dirty Dozen” inventory, a brief survey assessing Machiavellianism, psychopathy, and narcissism. For sadism, additional questions from a related scale were included. Međedović also gathered detailed information on each participant’s criminal history, including their first offense, whether they received corrective measures as juveniles, and instances of repeated offenses. Additionally, participants reported if they had engaged in problematic substance use, such as illegal drug use or alcohol misuse, before their incarceration.

The results showed that Machiavellianism was the most significant predictor of criminal behavior among the dark traits. Individuals with high levels of Machiavellianism were more likely to engage in repeated offenses, with this trait playing a particularly prominent role for men.

Machiavellianism was also linked to a higher likelihood of early criminal behavior, which, in turn, was associated with continued criminal activity into adulthood. This trait’s association with manipulation and deceitful behavior may explain why it stands out as a predictor of crime over time.

“Conceptually, the best candidates to explain criminal behavior from the taxonomy of Dark Tetrad traits are psychopathy and sadism,” Međedović told PsyPost. “However, our data showed that Machiavellianism is actually the most important for understanding criminal behavior.”

Psychopathy and sadism also showed some connections to criminal behavior, but to a lesser extent than Machiavellianism. Interestingly, psychopathy was related to problematic substance use, suggesting that individuals with this trait may use substances more frequently, possibly leading to increased chances of criminal behavior. Narcissism, on the other hand, showed a weak link to criminal activity and appeared to have a protective effect against substance use and repeat offenses.

Sadism showed unique effects based on gender, representing a risk factor for early criminal behavior and substance use among female offenders. This finding suggests that sadism may impact criminal behavior differently in women, although the reasons for this are still unclear and would benefit from further study.

“I believe that the most robust finding of the current study is that all Dark Tetrad traits are associated with criminal behavior, though to a different extent,” Međedović explained. “The result that Machiavellianism was the best predictor in our current study may vary across different samples and measures—we will evaluate this when we obtain more data on the associations between Dark Tetrad traits and criminal behavior in future studies.”

The results highlight that “personality is indeed important” when it comes to predicting criminal behavior, Međedović said. “Among other factors (which I would like to emphasize), dark personality traits can help us understand and predict criminal behavior. I highlighted ‘among other factors’ because the role of personality traits in crime should always be evaluated along with socio-economic predictors of criminal behavior that are varied—from general poverty and resource scarcity to particular situations that can promote criminal behavior.”

While this study provides important insights into the relationship between dark personality traits and criminal behavior, there are limitations. One major limitation is that the research was conducted on a sample of incarcerated individuals in Serbia, which may not represent all offenders or populations with dark personality traits.

“The sample was not representative, but this is really hard to achieve in prisoner populations,” Međedović noted.

Additionally, the measures for each dark trait were brief and may not capture the full range of each trait’s effects. For example, psychopathy is a complex trait that may involve impulsivity as well as emotional coldness, yet only certain aspects were captured in this study.

“Most importantly, our study was retrospective, meaning that the outcomes we tried to predict occurred earlier in life than when we collected data about personality traits,” Međedović explained. “Hence, there is no possibility of suggesting causal links. We do have data from developmental psychology showing that some forms of dark traits (e.g., callous-unemotional traits) can emerge early in development, but this still cannot help us make conclusions about the causal links between personality and crime in our current study.”

Future research could benefit from exploring these traits over time through longitudinal studies, which could clarify how these traits develop and influence behavior. More detailed measures, especially multidimensional assessments that explore various aspects of each trait, might also reveal subtler links between personality and crime. By further examining these connections, researchers and practitioners could enhance risk assessment tools for preventing criminal recidivism and improve rehabilitation strategies for those involved in criminal behavior.

The study, “Machiavellianism as a crucial Dark Tetrad trait for the prediction of life-course criminal behavior,” was published September 11, 2024.