Why Do People Kill?
We are not "just" looking at murderers here, but an example we often hear when looking at forensic profiling is the search for serial killers.
WHY do people commit murder?
Before looking further at psychological profiling in crime, we have to consider WHY do people commit murder? There is obviously no right answer here. A person who commits one murder in their whole life and feels remorse for it, is going to be a very different person to the serial killer who enjoys killing and kills many people. But even within the idea of “serial killer”, it is not that simple, there are thought to be more than one type of serial killer.
Types of Serial Killers
Ronald M. Holmes and T. Holmes suggest typology for serial killers. They suggested that there four types of killer.
The visionary killer will kill others because they believe they have visions from God, Satan, angels or demons. Their victims are often not related or connected to them.
Missionary killers will tend to murder a particular class, race or group of people to eliminate them. You could argue that Hitler was a missionary killer for killing the Jews, Gypsies and other groups in World War II.
Hedonistic killers are thought to gain intense sexual gratification from their acts of violence. Holmes and Holmes thought that there were two types of hedonistic killers –
- Lust Killers – Those who get sexual pleasure before and after the victim is dead.
- Thrill Killers – Killers who find their excitement fades when the victim is dead.
Control or Power Killers
These killers want to control and have master over their victim in a complete way. This will include when and how the person dies.
Some researchers argue that the power/control category is not necessary as all killers in the other categories have the need for power and control over their victim and do decide when and how the person dies.
The FBI formed the Behavioural Science Unit in 1974. They interviewed thirty six serial killers to try and understand their motivation and psychology. They stated that serial killers could be put into three groups –
Organised killers were those that planned their attack. The planning became a time consuming fantasy. They would choose their victim, stalk them carefully. They might carry weapons with them, but rarely kill at the place where they encounter the victim. Usually they take their victim to another location to commit the murder, then dispose of the body in another location. This makes it harder for the police to collect evidence as it is spread across different scenes. The killer will also follow the investigation in the media.
Ted Bundy is considered a perfect example of an organised killer. It is thought that he may have murdered up to one hundred women. He confessed to thirty homicides in his trial, but the true number of victims is unknown. Bundy was handsome and charismatic. He would approach a woman in a public place and ask for help, pretending he was injured or disabled. For example, he would wear a sling on his arm and ask for help. Or he would pretend to be an authority figure. He would then overpower them and assault them in secluded locations. He would sometimes visit the crime scene again and groom the victim’s body or perform sexual acts on the corpse. He decapitated at least twelve victims and kept their heads in his apartment at times as souvenirs. Sometimes, he would break into a house and bludgeon the victims to death.
He was captured in 1975 in Utah, but managed to escape twice. During the escapes, he committed more assaults, including three murders. He received three death sentences and died in the electric chair in Florida in 1989.
Disorganised killers do not plan, but attack suddenly. Their victim will just, unfortunately, be in the wrong place at the wrong time. The killer will not usually bring a weapon, but will use something they find at the scene, such as a rock or pipe. They do not dispose of the body, but make take souvenirs. It is easier to track them because they are disorganised.
Some killers cannot be classified. They may kill occasionally when they are drinking or taking drugs. They may be involved with other criminals who kill. This is a category for those killers who do not fit neatly into disorganised or organised killers.
The FBI model has been criticised as this can be confusing. Organised killers may be psychopaths who plan their crimes and often kill in cold blood. But disorganised killers could also be psychopaths, but may also be psychotic. Psychotic means that they have lost touch with reality. They may have hallucinations or delusions.
The Diagnostic and Statistical Manual of Mental Disorders (DSM) is a guide for mental health professionals. It describes a condition called antisocial personality disorder, which describes many of the people we would consider serial killers. With this disorder, the person has a disregard for the law and social norms. They usually have a long history of arrests and fights. Some are very skilful at lying. They may act impulsively with no regards for their safety or the safety of others. The symptoms will become obvious in their early teens. The condition is more common in men than women.
We often see “psychopaths” on TV or in films or in books. Psychopathy is a severe form of antisocial personality disorder. Psychopaths will have the same forms of antisocial behaviour, but they will also be very suspicious and highly paranoid. Robert D. Hare developed the Hare Checklist for psychopathy. It was renamed the Psychopathy Checklist – Revised (PCL – R). It has twenty criteria and the person is scored out of 40 on each criteria. It looks at antisocial behaviour. An average score is 4. A score over 30 means the person is a psychopath in America. The cut off score is 25 in the UK. The maximum score is 40. The scale is on a continuum. Some psychopaths may not be violent or commit murder, whilst others are.
For example, Aileen Wuornos killed seven men in Florida between 1989 and 1990. Each time, she claimed they tried to rape her, so she acted in self-defence. She was a serial killer and received a death by lethal injection in 2002. Her score on the scale was 32/40.
Peter Lundin scored 39/40. He killed in America and Denmark. He moved from Denmark to America when he was seven. He killed his mother with the help of his father and was imprisoned in America. On his release, he moved back to Denmark where he met a woman called Marianne Pedersen. He killed and dismembered her and her two sons.
But why do Murderers Kill?
Unfortunately, there is not always an obvious answer here either. We can study murderers and see what they did, try to understand their life, their childhood, their experiences and we can hope that it will lead us to an understanding of why a person might kill. This, ultimately, will hopefully help psychological profilers to develop effective methods of catching criminals quickly and effectively.
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