The earliest and most persistent explanations of criminal behaviour locate the flaw in the individual. From the “original sin” in Christian theology to antisocial personality disorder and psychopathy in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), the concept of bad people doing bad things has been a universal starting place for our approach to criminality (American Psychological Association, 2013).

The key question stemming from this approach is: What differentiates individuals who commit crimes from those who do not? Many psychological theories of criminal behaviour focus on identifying personality traits, characteristics, and developmental pathways believed to be shared by people who commit crime. Some theories focus on the temperament and personality people are born with (nature), while others focus on how life experiences shape people’s behaviours and attitudes (nurture).

Nature

Research on children has consistently found stable differences over the first three years of life across activity level, distractibility, adaptability, sensitivity and quality of mood. Tang et al. (2020) found that behavioural inhibition in infancy predicts shyness and introversion in adults thirty years later, suggesting that early temperament persists through the life span. Two temperaments associated with criminal behaviour are: 1) high sensation-seeking combined with low self-control, which leads to impulsive risk-taking and 2) negative emotionality, which leads to increased hostility and, if combined with callous emotional traits, increased cruelty (Delisi & Vaughn, 2014; Bonta & Andrews, 2017). Of these aspects of temperament, low self-control and impulsivity have received the most research attention and are considered major contributing factors in violent crime (Garofalo et al., 2018; Gilbert & Daffern, 2010; Kuin, et al., 2015; Gottfredson & Hirshi, 1990).

Researchers have long engaged in classifying humans into different categories of personality to predict differences in individual behaviour. The Myers-Brigg personality type indicator, rooted in the work of Carl Jung, divides people along four continuums: introversion or extraversion (E/I), sensing or intuition (S/N), thinking or feeling (T/F), and judging or perceiving (J/P), resulting in 16 main personality types (Myers, 1962). This theory suggests that differences in behaviour are largely due to basic differences in the ways individuals perceive and judge the world around them.

Another common current personality measure is the five-factor model of higher-order traits: extraversion, neuroticism, openness to experience, agreeableness, and conscientiousness (Costa & McCrae, 1992). Research applying the five-factor model to antisocial behaviour has typically found that antisocial behaviour is associated with lower agreeableness (less altruism, tender-mindedness, compliance and straightforwardness) and lower conscientiousness (less self-discipline, deliberation and dutifulness) (Jones et al., 2011). Overall, the core of the “nature” focus is the assumption that people behave consistently across time and situations, and this consistency allows us to predict future behaviour, including criminal behaviour (McCrae et al., 2000).

Nurture

Theorists that focus on “nurture” argue that personality develops in response to childhood experiences. Sigmund Freud’s (1901, 1924, 1940, collected in Freud, 2012) psychodynamic approach was one of the first theories to chart the development of personality through childhood. Freud proposed five stages of psychosexual development: oral, anal, phallic, latency, and genital. During each stage, sexual energy (libido) is expressed, and the reaction of parental figures determines whether the stage resolves successfully or not. If stages resolve positively, the resulting adult is able to “love, work, and play.” If developmental stages do not resolve successfully, the result is an adult who is likely to violate ethical and moral standards.

Erik Erikson’s psychosocial developmental theory extended Freud’s theory of psychosexual development throughout the lifespan. At each stage of life, individuals face developmental challenges on the road to self-actualisation. Early stages of childhood development determine whether a child will trust or mistrust the world around them, develop autonomy or shame in their own abilities, and perceive themselves as “good” by being rewarded for their initiative or “bad” for failing to live up to the expectations of parental figures. Later stages focus on identity, intimacy, productivity, and satisfaction with life (Erikson, 1950).

Erikson’s work informs Lawrence Kohlberg’s theory of moral development (Kohlberg & Hersh, 1977). Kohlberg asked people of various ages about their views on right and wrong in moral dilemmas and found that people’s reasons for deciding right versus wrong followed a predictable path, as shown in Table 7.5.

Kohlberg theorised that criminals would be more likely to show pre-conventional moral thinking. Research on criminal offenders has linked pre-conventional moral thinking to higher rates of recidivism, though, notably, research of this sort would not include criminals who had escaped the law (van Vugt et al., 2011). Watch Kohlberg’s Stages of Moral Development for more detail on Kohlberg’s theory and its three stages (each with two sub-stages) and a discussion of the famous Heinz dilemma.

Under “nurture” explanations of behaviour, parenting (usually mothering) is a major early shaping factor on the development of personality and morality. Two dimensions appear particularly important: support and control (Hoeve et al., 2009; Maccoby & Martin, 1983).

Baumrind (1991) created a typology of parenting styles differentiated by support and control, as shown in Table 7.6.

Research indicates that an authoritative style fosters higher levels of self-control, which is a protective factor against criminal behaviour. Rejecting-neglecting parenting is most linked to  violent behaviour (Maccoby & Martin, 1983; Steinberg et al., 1994; Chung et al., 2006).

Parental monitoring, which can be supportive or controlling, has also been linked to criminal outcomes. Recent research indicates that harsh control (physical/verbal punishment and intrusiveness), low warmth and low monitoring are particularly related to criminal and violent behaviour (Pinquart, 2017; Odgers et al., 2012).

Research supports the view that parenting involving warmth, active parental monitoring and consistent rules/expectations may protect against violent behaviour in youth (Fosco et al., 2012). Discipline that emphasises positive reinforcement over punishment appears to be the most effective (Halgunseth et al., 2013; Surjadi et al., 2013).

Although parents clearly influence their children, children also influence their parents. Gerald Patterson (1995) developed coercion theory to describe an escalation pattern of parents and children negatively influencing each other. If a parent gives in to escalating demands from their child, the child learns that they will get what they want if they intensify their anger and resistance; therefore, the child will use this tactic the next time they want something. If the parent increases their hostility in response, they effectively increase the level of demand their child must reach to succeed, thereby feeding a coercive cycle. Children also learn that coercive actions are effective in achieving one’s goals and may emulate this behaviour with others. Children engaged in frequent coercive interactions with their parents are more likely to have aggressive and oppositional behaviour (Patterson et al., 1992; Shaw et al., 1994; Shaw et al., 1998).

One challenge in parenting research is establishing unbiased ratings of parent and child behaviour (Pinquart, 2017). When rating themselves, parents will often respond in a socially desirable way, intentionally or not. Similarly, children’s behaviour ratings are potentially biased, depending on who is rating them. When ratings are given by researchers, it usually involves artificial settings that affect the behaviour of both parents and children. Finally, research on parenting relies on correlation because experiments cannot ethically expose children to different kinds of parenting. Correlation cannot determine causality; it can only identify a relationship between two variables, but it can not determine which variable caused which or whether a third variable influenced both.

Attachment theory (Bowlby, 1982) focuses on the quality of a child’s early connection to their primary caregiver and how it affects adult emotional and relationship functioning. Bowlby’s attachment theory posits that early caregivers must provide security: infants are completely dependent on their caregivers and must feel protected and trust they can rely on their caregiver to meet their needs. When that trust is strained or broken, a child forms a dysfunctional attachment towards their parents. Instead of security, they experience ambivalence, fear, or anger towards their caregiver, which leads to clingy preoccupation or dismissive rejection of caregivers. Early disrupted attachments translate into an inability to trust and rely on others in adult intimate relationships and may contribute to violence in intimate relationships (Dutton, 2007). Insecure attachments also affect how positively or negatively we view others, which can increase or decrease the likelihood of offending against others.