Unraveling the Origins of Serial Killers: Nature Versus Nurture

The debate as to the extent to which a serial killer is ‘born’ or ‘made’ is one that has been raging for over a century. According to the Federal Bureau of Investigation (FBI), serial killings or serial murder is described as “the unlawful killing of two or more victims by the same offender(s), in separate events” (n. d. ). On the one hand, some forensic psychologists believe that our biological makeup including our brain function and genetics influences our ability to kill. On the other hand, there are forensic psychologists who argue that the ability to kill comes as a direct result of our upbringing and social context. Although there is a plethora of reasons, both physiological and non-physiological which can be used in order to explain criminal behaviour, under which serial killings fall into, due to space restrictions we will only be looking at the following reasons: brain dysfunction (nature) and childhood (nurture). The nature-nurture debate aims to understand whether a behaviour is hereditary or whether it is acquired throughout an individual’s life. On the one hand, there is ‘nature’, which takes a deterministic view and argues that our behaviour is pre-determined due to our biological make-up. On the other side of the debate is ‘nurture’ which argues that behaviour is learned as a result of a person’s surroundings i. e. their early childhood and upbringing, social relationships and how they were raised (Cherry, 2018). This argument proposes that at birth, the human mind is in a blank slate, a ‘tabula rasa’, and it gets filled with knowledge acquired throughout a person’s life (McLeod, 2017).

Nurturists believe that through learning, behaviours and tendencies to stray from social expectations can be observed in childhood. It is how you were raised that ultimately determines your behaviour and actions. One key piece of research to support the ‘nurture’ debate was conducted by Albert Bandura in 1961 and named the ‘Bobo Doll’ Experiment. The aim of the study was to determine whether behaviour, such as aggression, could be learned through imitation (McLeod, 2014). In his study, Bandura found that children learned behaviours i. e. aggression through observational learning (learning by observing the behaviour of others). This would later form the basis of one of psychology’s greatest theories: Bandura’s Social Learning Theory (SLT) of 1977 where he expands on his idea that behaviour can be learned through imitation. Bandura’s research supports the ‘nurture’ debate because it demonstrates how behaviour, in this case, aggression, can be learned from our surroundings as the children in the study imitated the behaviours displayed by the model. Throughout our everyday lives, we imitate the behaviour of ‘models’ whether it is our parents, siblings, teachers or actors in films and without realising, we take inspiration from these people and endeavour to be like them. The ‘Bobo Doll’ Experiment provides scientific research supporting the ‘nurture’ debate and must, therefore, be taken into consideration when determining whether a serial killer is ‘born’ or ‘made’. The nativist view looks, in part, at our brain dysfunction to suggest that behaviour is inherited and therefore predisposed. One key piece of research which aims to look at brain dysfunction to explain criminal behaviour was conducted by Professor Adrian Raine, a British psychologist. Raine investigated the extent to which low activity of the prefrontal cortex could be used to explain violent behaviours such as murder.

The Professor led a study on an area of the brain known as the prefrontal cortex which is the part of the brain just above your eyes and behind your forehead. Low activity in this region of the brain is said to cause aggressive and impulsive behaviour and can be specified by a low heart rate. The prefrontal cortex is also responsible for personality expression, decision-making and regulating social behaviour. It plays a pivotal role in our self-control and enables us to control primitive impulses. Raine investigated the relationship between low activity in this region of the brain and criminal behaviour. He described the prefrontal cortex as “a bit like the emergency brake on behaviour”. By using Positron Emission Tomography (PET) scans, Raine was able to compare the brains of murderers and non-murderers and prove that impulsive murder may be, in part, attributed to brain dysfunction in the prefrontal cortex. Raine’s research is supported by Weiger and Bear who agreed that “aggressive behaviour is controlled at multiple anatomical levels within the human brain” (1988). Although low arousal in this area of the brain is partly inherited, it may also occur due to external factors such as if the mother was drinking alcohol during pregnancy or if there were complications during the child’s birth. Therefore, Raine stresses that in order to fully understand criminal behaviour, we must take a biosocial approach and focus on both biological and social aspects influencing the individual’s behaviour rather than just either one. One of the world’s most notorious serial killers, Harold Shipman is one person who could perhaps be said to support the ‘nurture’ argument and may be used to argue in favour of serial killers being ‘made’ rather than ‘born’. Harold Shipman was a British doctor born 14th June 1946 in Nottingham to a working-class family in an estate infamous for the rise in local domestic conflicts. His mother, Vera, instilled in him a superior attitude which mirrored her own philosophies and ideologies. Whilst his mother always dressed her son smartly including wearing a tie and dictating his play-mates, the young Harold had never displayed any outward resistance to his mother’s control.

Furthermore, Shipman was always a loner, who studied by himself for hours and never played with friends as he did not have any. Instead, he dedicated himself to fulfilling the superior attitude his mother had indoctrinated in him from a young age. He was nicknamed ‘Plodder’ due to the fact that Shipman was often seen carrying a backpack full of books every day from his home, across town, to get to school. His sexual fantasy structure is unknown but it is believed, among experts, that young Shipman developed a ‘God-complex’ around this time. ‘God-complex’ is a term used to describe a “personality flaw in human beings, especially those with great power, who perceive themselves to be omniscient and omnipotent, and treat others as mere mortals” (PsycholoGenie Staff, 2018). When Shipman was fifteen years old, his mother contracted terminal lung cancer. Shipman became her full-time caregiver whilst fully aware that his mother would soon die and leave him. After the death of his mother, in 1963 when he was just seventeen years old, Shipman kept to himself and attended school just as normal. With his mother gone, there was no one who would build his self-esteem and at this time, the young Shipman was said to feel under immense pressure and felt conflicted. Being his mother’s primary caregiver, Shipman was in control of her drug administration and this critical period of his life is said to be when he first experienced the feeling of power over life and death. This ultimate feeling of power is thought to have led him to become a doctor so that he could once again assume that position of power. At university, however, Harold Shipman “developed a superficial as a self-preservation mechanism” (Berry-Dee and Morris, 2006). In 1974, Shipman graduated from medical school and began his training as a junior doctor at Pontefract General Infirmary. According to the Shipman enquiry, a report published by the British government presenting the findings of their investigation into the murders committed by Harold Shipman, it was whilst he was at Pontefract General Infirmary that he had committed his first act of murder.

This is supported by psychologist Dr David Holmes who said that at that time, “Harold would have had some swelling; some strangely inexplicable pleasurable feelings […]and he would suddenly begin to feel he was in that powerful role, that controller of life and death” (Berry-Dee and Morris, 2006). The victim, a four-year-old girl, was a seriously ill patient of his at the hospital. Her mother had pleaded with Shipman: “please be kind to her” and it is thought that he mistook this favour as a cue to kill her and “he might have pretended that that was euthanasia, that he was doing that child a favour” (Berry-Dee and Morris, 2006). Whilst working at The Abraham Ormerod Medical Centre in Todmorden, West Yorkshire, Shipman was found to have ordered vast quantities of a painkiller called Pethidine claiming it was for his patients. In 1975, Shipman was eventually found guilty of the crime and had his medical licence, to practice in West Yorkshire, stripped from him. Humiliated, Shipman went to rehabilitation and vowed to return to medicine, which he did after two years, at a new medical practice in Hyde, Manchester. Here, he immediately began to gain the local community’s trust. Whilst it is unknown how many patients or victims Harold Shipman killed exactly, the method in which he killed them is certain. Shipman, “recreating the ‘care’ he gave to his dying mother” (Berry-Dee and Morris, 2006), would inject his patients with lethal doses of the painkilling drug morphine and watch as they slowly lost consciousness, before finally dying. Their deaths often took place in the patients’ own homes, where many of the deceased bodies were found fully clothed and sitting upright in either chairs or sofas. Shipman is suspected of roughly two hundred and eighty murders, making him, in terms of numbers, the world’s worst serial killer.

However, he was convicted of only fifteen murders due to a lack of substantial evidence to prove otherwise. When looking at sexual deviances in the case of Harold Shipman, he does not fit the stereotypical profile of the sexual serial killer. Whilst it is uncertain whether Shipman sexually assaulted any of his victims, there is no physical evidence to suggest that he did. It seems as though he was primarily driven by the desire to wield power over life and death. As a final act of power and control, in 2004, Harold Shipman committed suicide by hanging himself in his cell at H. M Prison Wakefield in North Yorkshire, knowing that he would leave countless questions in his wake. The case of Harold Shipman supports the ‘nurture’ debate due to the fact that his childhood and upbringing largely influenced his character. His mother, by preaching his superiority, had created a ‘God-complex’ in her son when he was just a young boy. Her parenting could be viewed by a nurturist as the main reason for the arrogance and egotism Shipman would grow to display.

Perhaps his isolation as a child, the fact that he had no friends and would spend endless hours revising rather than playing, like most children his age would, could also explain how Harold Shipman would grow to become the world’s worst serial killer. Having looked at both the ‘nature’ and ‘nurture’ side of the debate, it is evident that when trying to determine why an individual develops into a serial killer, we must look at both physiological and non-physiological factors. A person’s upbringing and social environment may lead to them committing serial murders if, for example, they were raised in a violent household or exposed to violent behaviour from a young age. On the other hand, a person may be predisposed to committing violent, serial murders as a result of suffering from brain dysfunction, in particular, low activity in the pre-frontal cortex is often attributed to violent, criminal behaviour. However, neither ‘nature’ nor ‘nurture’ alone can be used to explain criminal behaviour in its entirety but rather, as Raine (1997) suggested, we must consider both biological and social factors which may cause people to commit multiple murders at different periods in time.