Human behaviour is a complex topic because it is determined by various biological, social, and psychological factors. Depending on the factors influencing behaviour, a human being may act in a certain way without knowing why they had acted in such a manner. In Brain on Trial, David Eagleman explains the relationship that exists between neuroscience and criminal acts, and how this information can be used to build a better society with a justice system that is not ignorant of the facts of advances in brain science (121-123). This information can better equip those in the justice system to understand better why crimes occur and may recur, and help in determining the actual punishment to be meted against those who break the law.
In the past, it was difficult to determine the mental state in which an individual was when committing crimes of a grave nature, such as murder, arson, child molestation among others. In many cases, the jury listened to the witnesses’ accounts of what took place, drew a conclusion from that point, and proceeded with sentencing the individual accused for allegedly committing the crime without considering the individual’s mental state at the time of the crime. Although the insanity defence had been used extensively in the US to find certain defendants not guilty by reason of insanity (NGRI), a severe limitation to the initial practice was that individuals with even sociopathic and psychopathic disorders were found NGRI (Felthous S139). Later, it was decided that individuals with severe acute exacerbations cased by their disorders (e.g. schizophrenia or other psychotic disorders) were found incompetent to stand trial because they had not been aware of their actions at the time the alleged crime took place (Felthous S140).
However, lately there have been developments in the study of brain science that have proven that some individuals have committed their crimes oblivious of their knowledge at the particular moment of committing the crime, largely due to them suffering brain damage, which inhibited their self-awareness and their ability to regulate their emotions and actions. An example is the story of Charles Whitman, who shot and killed 13 people and wounded 32 others in August 1966 (Eagleman 115). Upon investigation, Whitman was found to have killed his mother and wife on the morning of the shooting. Whitman was aware of the changes in his brain that he felt were pushing him towards committing the heinous crime of murder. Whitman even visited a doctor once, but no solution was given to him for his violent impulses that overcame his free will. However, after the police shot him down after his rampage, an autopsy report indicated a tumour in his brain, to prove his concerns as raised in a suicide note he had typed before he went on his shooting spree.
Such a mental condition as the one Whitman suffered from exhibits itself when one is faced with frightening situations or experience some form of social phobia, but in his case, the mental condition was induced by a physical illness that could have been treated and prevented with a timely intervention. Cases such as Whitman’s have become so common, as juries have become more aware of the fact that brain activity may have a bearing on criminal acts. It is common to see a jury ordering a mental evaluation of a suspect during trial and use it to determine the outcome of the case. However, mental disorders alone account only for some cases of violent crimes. Research shows that in addition to psychological factors, various biological and social factors can also predispose an individual towards criminal behaviour, but the question is whether all factors inhibit their free will and make them incompetent to stand trial.
Explanations of Criminal Behaviour
Biological Explanations
Genes. In some instances, human behaviour is determined by the set of genes they carry. Studies have shown a particular type of genes increase an individual’s probability to commit violent crimes like robbery, aggravated assault, murder and sexual offense. According to Baum, carrying a low-activity Monoamine Oxidase A (MAOA-L) gene makes an individual more likely to engage in aggressive behaviour in cases when the individual feels threatened or neglected (288).
However, it is highly unlikely that genes alone predict criminal behaviour outcomes. The MAOA-L gene occurs in only one third of all criminals, so it is possible to conclude that carrying that gene alone is not sufficient to predict criminal behaviour (Baum 289). When the gene was studied in the context of childhood trauma, it was found that childhood neglect or maltreatment affected the behavioural development of the children significantly if they carried the MAOA-L gene (Baum 293). Therefore, a certain gene cannot determine behavioural development without the required gene-environment interactions, but it could determine resilience to traumatic events and contribute to the development of criminal behaviour when social factors support it.
Brain Changes. Biological changes bring about responsive changes in humans, especially in the brain. This affects the process of decision-making and indents it towards irrational human behaviour. There are many hidden desires and drives that are not detected behind the neural machinery of socialization. Once a vital part of the brain like the frontal or temporal lobes or the amygdala, which is essentially involved in regulation of emotion are affected in the slightest, free will become inhibited and criminal behaviour begins to emerge as they can no longer control their impulses. While genes can determine neural development in those regions of the brain, various environmental factors can also determine the trajectory of neural development. Substance abuse and traumatic brain injuries (TBI) are the most common causes of brain changes associated with criminal behaviour.
Substance abuse alters the mechanisms responsible for learning and memory. Studies found that substance abuse damages various regions of the brain located in the frontal cortex, such as the insula and medial regions, which are responsible for self-awareness and self-regulation (Goldstein et al. 374). Once those regions are damaged, the affected individuals lose their rational decision-making abilities and behavioural regulation, which can lead to aggressive and criminal behaviour.
TBI is also considered a significant factor that determines criminal behaviour. While it is estimated that TBI affects 8.5% of the world’s population, the highest prevalence of TBI has been recorded among prisoners, and the prevalence of TBI in that group can range up to 60% (Williams 3). The highest risk a group for violent criminal behaviour that results from TBI are young people during childhood, adolescence, and young adulthood. Because their brain is not yet completely developed before they reached the age of 20, a physical injury that damages the frontal lobes can impair impulse control and cause the development of temperamental behaviour (Williams 10). Some examples of changes in behaviour caused by TBI include antisocial behaviour and immature behaviour during conflict resolution, and those behaviours can ultimately lead to violent criminal behaviour and incarceration.
There is a need to have a judicial system that understands better the fact that human beings do not have the same capacity to make sensible decisions. Biological factors that affect human behaviour are beyond the control of free will. The more it becomes evident that human choices are very difficult to detach from their neural circuitry, the more the foundations of the judicial system are precariously strained. Therefore, using biological factors as screening measurements for predispositions to criminal behaviour could
Psychological Explanations
Personality Traits. Some examples of traits often elevated in individuals who display criminal behaviour include Urgency and Sensation Seeking while Premediation (i.e. the inability to delay actions to consider long-term plans) and Preseverance (i.e. poor self-discipline) are traits that individuals with criminal behaviour often lack (Cross, Copping, and Campbell 101). However, the traits associated with criminal behaviour are dependent on the measurement instrument. For example, the Multidimensional Personality Questionnaire (MPQ) measures impulsivity on the Control vs. Impulsiveness scale while the Social Problem Solving uses the Impulsivity/Carelessness scale (Cross, Copping, and Campbell 101). In all cases, it appears that impulsive personality traits are the most commonly associated traits with criminal behaviour.
The general theory of crime explains that self-interest and low self-control are the main personality traits that caused criminal behaviour. A person acting out of self-interest pursues pleasure while avoiding pain while a person with low self-control cannot regulate emotions and aggressive actions effectively (Cross, Copping, and Campbell 97). In other words, elevated Urgency and Sensation Seeking traits could contribute to criminal behaviour when an individual acts out of self-interest.
The general theory of crime has been criticized by Wikström and Treiber because it considers that self-control is a trait rather than a situational concept (238). However, self-control can be considered the outcome of various personality traits, such as Premediation and Preseverence, which are often lacking among individuals with criminal behaviours. Therefore, while self-control itself can be considered as an ability dependent on situational factors, various scales like the MPQ consider control a personality trait, and increased impulsivity traits indicate that the person will consequently display low self-control. Separating self-control from personality traits and considering it a situational concept is not possible. With low self-control and high impulsivity, the individuals’ behaviours may vary from aggressive sexual behaviour to gambling, murder (as exhibited earlier In Whitman’s case), overeating, drug addiction, public nudity, robbery, and other socially unacceptable forms of behaviour.
Mental Disorders. Not all mental disorders predispose an individual toward violent criminal behaviour. However, severe forms of mental illness are associated with aggression symptoms, and the criminal behaviour of violent offenders can sometimes be explained by illnesses such as post-traumatic stress disorder (PTSD) and schizophrenia.
In PTSD, violent criminal behaviour can be associated with the brain changes that occur in affected individuals. According to Liberzon et al., the PTSD patients displayed an over-activation of the nucleus accumbens, but various other structural abnormalities were also found in the limbic regions of the brain, such as the hippocampus and the amygdala (823-824). Those regions are associated with processing memory and can compare it to previous experiences, so they can also trigger defensive patterns in response to negative stimuli. However, those systems are hyperactive in PTSD, which can cause detrimental behavioural patterns including violent behaviour.
Schizophrenia is mainly a genetic disorder because genes account for 80% of schizophrenia cases (Os and Kapur 638). Environmental factors can also trigger schizophrenia, but it is highly unlikely for an individual to develop it without the proper genetic background (Os and Kapur 637). It is important to note that extremely violent criminal behaviour is rare in schizophrenia patients. The study by Swanson et al. found that only 3.6% of their sample, which consisted of more than 1,400 participants, engaged in serious violent acts while 80.9% did not report any previous acts of violence (493). Therefore, demographic factors (e.g. young age), developmental factors (e.g. childhood conduct issues), and illness severity appear to determine criminal behaviour in people with psychotic disorders.
Although PTSD, schizophrenia, and other mental disorders do not necessarily result in violent behaviour, acute episodes associated with those disorders often inhibit mental clarity and cause impulsive reactions to situations that are perceived threatening. Those who suffer from severe forms of these mental conditions often end up being arrested and charged in courts of law, where they try to explain to the judge and jury why they performed those acts for which they were arrested. At this point, the offenders and their lawyers may not be in possession of information that may shed light on the changes in the balance of their brain chemistry, but a forensic psychologist may be ordered to evaluate the offender’s mental state at the time of the crime to determine whether the perpetrator is able to stand trial or whether mandatory mental treatment should be prescribed.
Social Explanations
Socioeconomic Status. The correlation between poor socioeconomic status and crime has been noted by Aristotle, who claimed that “poverty is the parent of revolution and crime” (Pol. II.6, 1265a28-1265b18, trans. Jowett). Contemporary research shows that there is a significant difference in reward perception and planning between people who were brought up in wealthy environments and those who grew up in poverty, so Aristotle’s idea of poverty is still applicable to the causes of crime in contemporary society. For example, the study by Griskevicius et al. found that it is possible for individuals who were raised in poorer socioeconomic conditions to engage in more sensation-seeking behaviours and pursue immediate rewards than the people who were raised in resource-abundant environments (1025).
The findings by Griskevicius et al. are consistent with the life history theory, which suggests that ecological variables (e.g. unpredictability and resource scarcity) associated with poor socioeconomic status determine behavioural outcomes (1018). Because pursuing immediate rewards is can be the consequence of growing up in an environment with fewer resources available, the individuals will more likely take actions that satisfy their desires and avoid discomfort, and that behavioural outcome is also consistent with the general crime theory that suggests self-interest is the key determinant for criminal behaviour.
Childhood Environment. Various ecological factors can affect the individual’s development starting with pregnancy. For example, maternal stress and substance abuse by during pregnancy can determine the brain development of the child (Eagleman 115). During infancy, physical abuse, neglect, and head injury can instigate mental development issues. Exposure to substances such as lead can cause brain damage and make children less intelligent or more aggressive and impulsive (Eagleman 116). Those characteristics and traits are commonly associated with criminal behaviour, so the impact of the environment on criminal development can begin already during pregnancy.
Whether in form of neglect or maltreatment, childhood abuse is a significant predictor of negative life outcomes, such as mental illness, substance abuse, and criminal behaviour. According to the psychodynamic theory, a person must develop a healthy ego and superego during childhood, but various environmental factors like neglect and abuse inhibit the development of the superego. With an underdeveloped superego, the person cannot understand social norms and ethical behaviour. In psychodynamic theory, those individuals are referred to as “the week superego type” and they are more likely to engage in criminal behaviour than other individuals (Andrews and Bonta 89).
The social learning theory can also be used to predict criminal outcomes because it suggests that children learn by imitating their parents and peers. During early childhood, the parents are the main role models, and their behavioural patterns are adopted by their children (Van de Rakt et al. 378). Therefore, the presence of a criminal father can lead to the increased rates of criminal behaviour among children who learn that behavioural mode from the criminal parent.
The study by Van de Rakt et al. also shows that the presence of a father who engages in criminal behaviour is necessary for internalising criminal behaviour at an early age (378). However, if the father is deceased or absent, the children will less likely adopt criminal behavioural patterns and face convictions in the future (Van de Rakt et al. 384). Although parental divorce is considered a stressful event in a child’s life, divorce can act as a protective event that decreases the father’s influence on the child’s development (Van de Rakt et al. 386). Therefore, in some instances, the criminal behaviour is inherited from one of the parents during the learning process in childhood, which entails replicating the behaviours the children observe in their parents.
Practical Implications
There is a need to create a legal system that is aware of the science behind criminal behaviour and is more willing to use the basis of science to regulate criminal behaviour and develop effective and meaningful ways of delivering punishment to criminals. In order to achieve that goal, there should be a clear comprehension that there is very little “free will” when human actions are examined scientifically, but there needs to be a clear distinction between individuals who engage in criminal behaviour consciously as opposed to those whose mental conditions make them incapable of understanding or regulating their own actions.
It is important to distinguish between the absence of free will and the individual’s lack of self-regulation. While substance abuse and TBI can damage brain regions that determine impulse control and emotional control, the lack of control over oneself should not be considered equal to the lack of free will. In mental disorders that can cause acute psychotic episodes, a person loses self-awareness completely, so they are clearly incompetent to stand trial for their actions. In the context of impulsivity, which can be caused by physical injuries, substance abuse, or personality traits, it is clearly more difficult to regulate behaviour given those factors, but it is not impossible if the individual has enough self-awareness to learn emotional regulation and coping strategies. Therefore, they do not lack “free will,” but they need to invest more time learning self-regulation.
According to scientific data, the responsibility for engaging criminal behaviour can always be attributed to certain personality traits, genetic influences, mental states, and environmental influences. When observing criminal behaviour through a scientific lens, the individual accused for criminal behaviour appears to have little control over behaviour, which is not an acceptable premise in creating sentencing procedures for the judicial system. Instead of liberating the individual, the system could be remodelled to accommodate the customization of sentencing by providing opportunity for rehabilitation and offering incentives for good behaviour in the society (Eagleman 122).
The legal system is slowly adopting methods of dealing with discoveries in neuroscience to make better judgements and deal with crime in a more humane and cost-effective manner as opposed to allocating money for prisons while some cases only require medicine to find a lasting solution. At the moment, the court can order a psychological assessment to determine whether the individual accused of committing a crime was aware of his actions at moment the alleged offense took place. In that case, the forensic psychologist is responsible for collecting information about the individual’s medical and family history and conduct an assessment through interviews and standardized instruments. If the psychologist determines that the individual’s disorder had inhibited the individual’s self-awareness at the time the alleged crime took place, the court will determine that the individual is incapable to stand trial. Therefore, instead of a prison sentence the individual will receive mandatory psychological treatment instead. In order to prevent abusing the system, the tests admissible in court need to differentiate between mild disorders in which individuals could still manage to regulate their actions and severe mental disorders that inhibit self-awareness and the knowledge of social norms (Felthous S140).
It is imperative to have a judicial system that is sensitive to the fact that many types of behaviour that are considered socially unacceptable have a basic biological explanation, as proven by technology in cases of schizophrenia, epilepsy, brain tumours, and other disorders. There should be a close working relationship between medical experts and the courts, to limit situations where an individual is forced to serve time in prison for crimes committed either unconsciously or beyond the control of the offender due to biological or psychological problems.
Finally, the understanding of predispositions to criminal behaviour can be used to decrease the prevalence of crime through intervention programmes that serve as prevention strategies rather than mechanisms for punishing past criminal behaviour. If individuals show personality traits associated with criminal behaviour (e.g. impulsivity, sensation-seeking, etc.), an intervention programme may be used to help the individual learn emotional regulation and improve self-awareness, so that they could prevent themselves from engaging in violent criminal behaviour.
Works Cited
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