When crime is genuinely driven by rational choice, the perpetrator commits the act for personal gain or satisfaction, with their behavior entirely under their control. However, the extent to which external factors may interfere with and undermine their capacity for free will becomes a critical question. This query has led to the development of numerous theories, each aiming to elucidate criminal behavior through specific factors. These theories generally fall into three categories: psychological, biological, and social. In reality, human behavior is the outcome of intricate interplays among numerous elements. Instead of providing an exhaustive summary of countless theories, this research paper concentrates on the principal factors influencing the manifestation and inhibition of criminal behaviors.
Social Factors in Criminal Behavior
The criminological literature offers an extensive array of environmental factors that are causally associated with criminal behavior. These factors encompass various aspects of development, society, and economics. For instance, poverty is frequently identified as a socioeconomic condition linked to criminal activity. The stress, frustration, and strain experienced by individuals lacking the financial means to fulfill their needs and desires through legitimate avenues can incline them toward criminal acts, unlike their affluent counterparts who have access to lawful resources. Notably, poverty can also entail nutritional deficiencies, which can exacerbate issues like learning disabilities and poor impulse control. These cognitive dysfunctions have been recognized as precursors to delinquency and eventual criminality. Consequently, one’s position in the social hierarchy, often measured by income level, can significantly contribute to criminal behavior by influencing brain function.
Growing up in an environment where parental violence is commonplace can mold children’s behavior, making them more prone to responding to their problems through violent means. While aggression and violence are distinct concepts, their correlation is evident. Psychologist Albert Bandura has underscored the role of social learning in the development of aggressive behavior. Exposure to a violent role model may serve as a catalyst for preexisting psychological and biological factors that predispose an individual to aggressive conduct. This phenomenon may elucidate why, in cases where a father assaults their mother, only one of the two sons grows up to exhibit similar behavior—additional factors render him more susceptible to the influence of the violent model. Conversely, the nonviolent son may exhibit resistance to this influence, possibly due to individual “protective” factors like a high IQ.
Extensive literature delves into the concept of a “cycle of violence,” where individuals who have experienced childhood abuse and neglect are predisposed to engage in violent behaviors in adulthood, perpetuating violence across generations. Similarly, research has explored the repercussions of childhood bullying, revealing that victims may later become aggressors themselves. Animal experiments have shown that exposure to inescapable threats can alter specific brain chemicals related to aggression and its inhibition. Consequently, once-docile animals may exhibit inappropriate and excessive aggression, often victimizing smaller, weaker animals, akin to becoming “playground bullies.” In essence, changes in the environment, such as exposure to inescapable threats, lead to biological changes that subsequently drive alterations in behavior. Empirical studies on child maltreatment have unveiled not only psychological problems but also structural and functional damage to the developing brain, potentially serving as an adaptive mechanism in dangerous environments. Nevertheless, these neurobiological effects tend to predispose individuals to various psychiatric conditions, aggressive behaviors, and stress-related illnesses. Resilient children, who thrive in high-risk conditions, often possess cognitive abilities, notably higher verbal intelligence, enabling them to adapt to stressful environments. Understanding the mechanisms underpinning resilience may reveal deficits in those who succumb to the adverse effects of disadvantaged or abusive childhoods, frequently resulting in delinquency and criminality.
It is important to note that the majority of impoverished individuals are not involved in criminal activities, and most individuals growing up in abusive households or experiencing bullying do not become criminals. This raises pertinent questions: What distinguishes those who engage in criminal behavior from others facing similar circumstances but remaining law-abiding? Furthermore, why do individuals who do not encounter such adversity commit crimes? The answers to these inquiries lie in the fact that social factors impact individuals differently. The psychological and biological constitution of an individual largely determines how external forces influence their behavior. While social factors undeniably play a significant role in criminal behavior, their effects depend on an individual’s psychological and biological makeup. This perspective does not downplay the influence of social factors but underscores that their impact varies based on individual differences. Ultimately, it is the individual who makes the choice to act, whether criminally or otherwise.
Psychological Factors in Criminal Behavior
Criminal courts place significant emphasis on the psychological aspects underpinning criminal behavior, primarily through the requirement of mens rea. However, research highlights the intricate relationship between an individual’s psychology and their biological foundation. The mind and brain share an inseparable connection, where an individual’s psychological state or mental status, whether at a crime scene or in a courtroom, involves intricate biological mechanisms.
Forensic psychologists often delve into the study of psychopathology, focusing on diseases and disorders of the mind. It’s crucial to note that the majority of individuals with mental disorders do not engage in criminal activities. Nevertheless, research indicates that rates of serious mental disorders among prison inmates are three to four times higher than those in the general population. While this disparity doesn’t necessarily imply a direct causative link between psychopathology and criminal behavior, it underscores the significance of mental disorders as potential contributing factors to criminal conduct.
The link between criminal behavior and mental disorders is intricate and multifaceted. Major mental disorders, such as psychosis, are characterized by false perceptions (hallucinations) and erroneous beliefs (delusions). Recent research has established a connection between schizophrenia, a type of psychosis, and an elevated risk of engaging in violent criminal activities. It’s important to note that individuals with psychosis are not typically prone to committing random acts of violence against strangers, as often portrayed in popular media. Instead, the violence is usually directed towards significant individuals in their lives.
Studies on hallucinations in individuals with schizophrenia have unveiled the neurological basis for these false perceptions. Auditory hallucinations, for instance, coincide with abnormal neuron activity in brain regions responsible for processing sound, even in the absence of external auditory stimuli. This neurological perspective enables researchers to ask more focused questions, such as why specific brain regions misfire without external stimuli, rather than vague inquiries like, “Why do schizophrenics hear voices?” Consequently, the impetus for violence in a person with schizophrenia, when driven by voices commanding harm, seems to stem from aberrant neural activity.
Among the various mental disorders recognized by clinicians and researchers, the majority do not fall under the category of psychoses. Instead, they encompass disorders related to personality, impulse control, and similar traits. Psychopathy, a subtype of personality disorder, manifests as a combination of specific affective, interpersonal, and socially deviant behaviors. While psychopaths constitute only around 1% of the general population, they are estimated to represent approximately 25% of the prison population. The nature of psychopathy, marked by a lack of remorse for antisocial actions and a deficit in emotional empathy for those whose rights are violated, makes psychopaths particularly well-suited for criminal activities. While not all psychopaths engage in criminal behavior (many still exhibit behaviors disregarding consideration for others), those who do tend to have significantly higher rates of recidivism compared to non-psychopathic offenders.
Despite the distinction between psychopathy and psychosis, psychopaths exhibit dysfunctional neurobiological mechanisms related to emotions, cognitions, thoughts, and attitudes. According to psychologist Robert Hare, genetic and other biological factors contribute to the deviant personality structure of psychopaths, while environmental influences may shape how the disorder manifests in their behavior. Advanced imaging techniques like positron emission tomography and single-photon-emission computed tomography scans have identified specific brain regions that function abnormally in violent psychopaths. Notably, the prefrontal cortex, a part of the frontal lobes responsible for rational decision-making and impulse control, often appears underaroused in psychopaths, rendering it ineffective in managing emotional impulses. This underarousal of the prefrontal cortex can lead to impulsive behaviors, including criminal acts.
Cognitive abilities play a substantial role in criminal behavior. When IQ is used as a measure of intelligence, research consistently shows that offenders tend to have lower scores compared to non-offenders. Individuals with lower intellectual abilities often struggle with delaying gratification, controlling their impulses, and understanding alternative ways to achieve their desires. Significant intellectual impairment can reduce inhibitions against causing harm because individuals may lack an understanding of the wrongfulness of their actions. While environmental factors can influence the development and expression of cognitive abilities, research indicates that there is a significant hereditary component to these traits.
The concept of emotional intelligence holds promise for a more comprehensive understanding of chronic criminality. Individuals with low emotional intelligence, who have limited insight into their own behavior and lack empathy toward others, are less inhibited when it comes to violating the rights of others. Brain injury, particularly to the ventromedial prefrontal cortex, has been associated with the onset of reckless and antisocial behavior, including violence, without experiencing remorse. This suggests that specific frontal lobe functions related to moral judgment are impaired in chronic offenders.
A psychoanalytic perspective highlights the often-neglected role of traumatic events during early childhood in the mainstream literature on criminal behavior. In the context of twenty-first-century technology, Freudian constructs can be reexamined and recast as specific neurobiological factors. For instance, Freud’s concept of the id, responsible for generating unconscious and primitive urges, may correspond to the limbic system, which includes brain structures involved in basic emotions, motivation, and memory. The ego, representing the rational aspect of personality that mediates the self-centered demands of the id, could be associated with the development of the frontal lobes during childhood. This rational component negotiates with the emotional and impulsive id.
Furthermore, Freud’s superego, representing the moral aspect of personality, may partially reside in the ventromedial prefrontal cortex. Damage to this brain region has been linked to remorseless antisocial behavior. Reinterpreting Freudian constructs in this neurobiological manner does not negate their validity but rather provides them with the potential for empirical validation.
It is essential to recognize that when discussing disordered mental states or mental diseases, we must also consider the underlying neurobiological processes. Regardless of the psychological issue at hand, it is no longer possible to discuss the psychological factors associated with criminal behavior without simultaneously addressing the biological factors. These elements are inextricably intertwined and must be considered together in understanding criminal behavior.
Biological Factors in Criminal Behavior
Biological factors play a crucial role in mediating the numerous social and psychological factors that increase the risk of criminal behavior.
Optimal brain function relies on a proper diet. Complex carbohydrates are broken down into glucose, which serves as the brain’s fundamental fuel. Various nutrients are involved in converting glucose into energy, and a deficiency in any of these essential nutrients compromises brain function, reducing available energy. The frontal lobes of the brain, responsible for rational thinking, behavior organization, and emotional impulse moderation, require twice the energy compared to more primitive brain regions. Depletion of energy levels impairs higher functions, allowing uninhibited lower brain activity. Consequently, emotions can dominate our behavior when energy levels are low. Malnutrition can impair cognitive function, making antisocial and aggressive behaviors more likely.
Among diagnosed illnesses associated with violent behavior, substance abuse ranks highest. Alcohol, for example, disinhibits individuals, leading to domestic violence, aggravated assault, murder, and rape, as evident in police reports. Substance abuse has a particularly detrimental impact on individuals with preexisting mental disorders, exacerbating their dysfunction. Alcohol itself does not cause violent behavior but can trigger violence in those already prone to it due to other factors.
Exposure to environmental toxic agents such as pesticides and lead can delay or impair intellectual development, affecting behavior and its regulation. Teratogens, which interfere with normal embryonic development, play a crucial role in predisposing some individuals to a life of crime. The consequences of cognitive deficits and behavioral issues resulting from factors like prenatal exposure to drugs and alcohol are well-documented in the literature.
Neurotransmitters play a critical role in conducting electrochemical impulses within and between regions of the brain, as well as throughout the body. Imbalances in neurotransmitter systems have been linked to numerous psychiatric disorders. One such neurotransmitter, serotonin, plays a vital role in regulating emotional states. Laboratory experiments have shown that lowering serotonin levels can lead to impulsive and aggressive behavior. The observation that childhood abuse and neglect can result in permanently reduced serotonin levels is significant for understanding the origins of violence.
Hormones, like neurotransmitters, function in a similar manner but are released into the bloodstream rather than between neurons. Abnormally high levels of circulating testosterone, a sex hormone associated with the drive to dominate and compete, have been linked to excessive aggression. Instances of “roid rage” in bodybuilders who use anabolic steroids and exhibit extreme and uncontrollable violence illustrate this effect. Research on stress hormones, such as low levels of salivary cortisol correlating with severe and persistent aggression, underscores the importance of hormonal contributions to criminal behavior.
Studies on skin conductance, heart rate, and brainwave activity have connected low arousal to criminal behavior. In fact, in young children, these psychophysiological conditions have been reported to accurately predict later delinquency. Collectively, these studies suggest that the brains of chronic offenders function differently. As we continue to identify factors associated with criminal behavior, we grapple with a critical question: To what extent are these factors genetically determined?
A range of methodologies, including studies involving twins and adoptees, chromosomal abnormalities, and DNA polymorphisms, have been utilized to investigate the role of genetic factors in criminal behavior and aggression. While the discovery of a “crime gene” is not expected, it is evident that certain genes code for neurochemicals associated with various behaviors. For instance, a specific, though rare, mutation has been identified in a gene responsible for an enzyme affecting the levels of specific neurotransmitters in the brain. This mutation has been linked to a predisposition toward impulsive and excessive aggression and violence in affected individuals within a family.
Behavioral genetics studies provide support for the notion that aggressive behavior has a moderate heritable component. Aggressive behaviors are advantageous for males of a species as they compete for territory and mates. Evolutionary psychology suggests that traits promoting reproductive success are selected and passed down through generations. Primatologist Ronald Nadler argues that sexual aggression is inherent in the behavioral repertoire of great apes, our close biological relatives. Human males, driven by their procreative instincts, may have a natural inclination to seek multiple partners, increasing the chances of species survival and gene transmission. However, most males do not engage in rape, largely due to socialization. Rapists are individuals who have not been effectively socialized against such behavior. This example illustrates how specific psychosocial risk factors, such as low intelligence, can elevate the likelihood of criminal and violent conduct, such as rape.
The long-standing tradition of viewing crime as a product of voluntary actions, unaffected by aberrant psychological or biological processes, is being challenged. Ultimately, it may be psychologist Adrian Raine’s bold conceptualization of criminality as a clinical disorder that aligns best with emerging knowledge. Embracing this perspective would necessitate a reevaluation of our concepts of crime, punishment, and treatment. If criminal behavior, particularly impulsive violent behavior, is inherently pathological, it holds far-reaching implications. Courts are wise to exercise caution in their determinations of culpability. As behavioral science research and technology advance, it is likely that the growing body of data will, over time, provide persuasive insights.
- Hare, R. D. (1993). Without conscience: The disturbing world of the psychopaths among us. New York: Pocket Books.
- Raine, A. (1993). The psychopathology of crime: Criminal behavior as a clinical disorder. New York: Academic Press.
- Salovey, P., & Mayer, J. (1990). Emotional intelligence. Imagination, Cognition, and Personality, 9(3), 185-211.
- Strueber, D., Lueck, M., & Roth, G. (2006, December). The violent brain. Scientific American, 20-27.
- Teicher, M. H. (2002, March). Scars that won’t heal: The neurobiology of child abuse. Scientific American, 68-75.
- Widom, C. S. (1989). The cycle of violence. Science, 244, 160-166.