Can we predict the likelihood of schizophrenics committing

homicide?

Name: Kiri Madhani

Student ID: 4162347

C83PAD

Supervisor: Professor D. Clarke

1 Contents

Page

1. Introduction 3

a) Schizophrenia 3 b) Schizophrenia & Homicide 3

2. Can homicidal behaviour be forecasted? 4

3. Models and theories surrounding SZ and homicide 6

4. Can we forecast a schizophrenic’s likelihood of committing homicide? 8

a) The type of homicide 9 b) The victim 9 c) The location 10

5. Practical implications of being able to forecast homicide in schizophrenic people 11

6. Conclusion 12

7. References 14

2 1. Introduction a) Schizophrenia

In the UK, approximately 330,000 people were recorded to have schizophrenia in 2010 (The National Survey of Psychiatric Morbidity). Schizophrenia is a mental illness that affects 24 million people worldwide. The incidence of schizophrenia is 0.03% in the general population, the prevalence however is higher (0.7%) due to schizophrenia having a high rate of reoccurrence and with it being a mostly long-term illness (WHO, 2014). According to the DSM-V, schizophrenia has a plethora of symptoms including, hallucinations, delusions, lack of emotions and empathy, thought disorders and reduced drives, all of which contribute to ‘social and/or occupational dysfunctions.’ With the medical perspective on mental health becoming a much more accepted one, research into how mental illness affects trends in behaviour is also becoming more apparent. Mental Health Today stated that ‘there were over 50,000 uses of the mental health act in 2012/13, the highest it’s ever been.’ Research is veering down the pathway of assessing trends that are high in patients with mental health problems and attempting to establish links between those behaviours and the increasing mental health cases. Homicide trends are an example of a link made with mental health; can we establish a trend that will allow prediction of homicidal behaviour and potentially prevention of it? b) Homicide

When talking about homicide, all types (e.g. serial, single, mass) are encompassed. The UNODC (United Nations Office on Drugs & Crime) reported 437,000 counts of homicide worldwide in 2012. In 2012/13 there were 551 counts of homicide in the UK alone. There has been much research into homicidal behaviour amongst those diagnosed or suffering from schizophrenia. Erb, Hodgins, Freese, Müller-Isbener and Jöckle (2001) found an increased risk of 16.6% in schizophrenics compared to the general population. ‘Schizophrenia is a severe and usually chronic or recurrent illness associated with a high suicide risk and relatively high homicide risk. It is commonly associated with substance misuse’ (Lodge 2009). Looking at research and statistics, opens up an avenue for predictability, if rates of homicide are high in those with schizophrenia, forecasting of

3 homicidal behaviour is surely possible? If we can predict homicidal behaviour, then this alone would contribute to a much safer society to live in, if we can predict, we can prevent. Not only do effective methods of prediction need to be established, these methods need to be applicable to predicting the behaviour of schizophrenics.

2. Can homicidal behaviour be predicted?

In order to predict how a particular individual will behave in general, certain factors need to be established, e.g. age, gender, ethnic background as well as the factors of personality differences and preconceived biases. Relevant predictions of how individuals may behave could have implications for important life events e.g. prevention of homicidal behaviour and criminal offences in certain individuals. Homicidal behaviour is notoriously impulsive, one that is assumed by most as unpredictable. Research surrounding homicidal behaviour is not as common as other areas of violent crime, due to factors such as sensitivity during data collection, less frequent occurrence and the often one-sided account of events, due to the victim being deceased. Farrington (1987) explains how the prediction of crime is useful with regards to preventing further offending and is the case more so in chronic offenders, homicide offenders often falling under this category. Farringdon additionally explains that identification of risk factors is key to increased predictability of committing violent crime, one of the standout factors being substance abuse. Although this research is dated, it demonstrates an underpinning finding regarding risk factors as a basis for future behaviour. Loeber et al. (2005) uses a strategy of quantifying risk factors to help make predictions of those likely to commit homicide. They go on to explain that there is no one risk factor that predicts homicide on its own. Risk factors therefore should be ‘mapped’ with homicide as a central factor to demonstrate that often multiple factors are linked to homicidal behaviour, and the relationships between these risk factors that are also apparent. For example we know that substance abuse is a factor contributing to homicidal behaviour, as is mental illness. We also know from previous research (Meuser et al. 1990; Dixon 1999) that substance abuse is highly co-morbid with schizophrenia, we know that schizophrenia links to a higher likelihood of committing homicidal behaviour, so a potential link is already established.

4 Berk et al. (2009) more recently deduced that offenders who fall under the bracket in which they are likely to commit homicidal behaviour or attempt to do so are in a group together, sharing certain characteristics associated with the behaviour, viewed as risk factors. Some of the most common risk factors seen in those that commit homicide are violent fathers, psychiatrically hospitalized mothers and suicidal tendencies (Lewis et al. 1985), research such as this is important for us to be able to draw together ‘stand out’ factors that should be noted in individuals who have come into disrepute with the law and may pose threat of recidivism e.g. homicide. Recent studies have shown that common risk factors, calculated using correlations are low education, low socio- economic status and broken families. Often homicide is not the perpetrators first crime and results from progressive criminal activity, starting with petty crimes such as theft. Having low income and education is a strong contributor for an individual to be involved in this progression. Age is a risk factor that can be used to help predict homicidal behaviour. The average age of perpetrators of homicide is 27.5 years (Hickey, 1997). Age narrows down the target audience for intervention and makes it easier to explore links with other factors that may contribute to homicidal behaviour such as schizophrenia.

A model proposed by Weatherby, Buller & McGinnis, (Buller-McGinnis Model) aimed to account for the separations between notorious serial killers and the general population. They investigated factors such as family background, childhood behaviours, and education and identified two that were found in most serial killers - poor childhood social environments and isolation. Researchers have also established models that aim to identify one contributory factor over another to explain why certain behaviours such as homicide may occur. MacDonald (1963) looked at ‘childhood cruelty towards animals, frequent bed-wetting and fire setting’ as factors contributing to violent, cruel behaviour, ascertaining a triad of behaviours. He suggested that these factors led to stress at a young age, with the potential of engaging in maladaptive behaviours. Hickey (2002) explained how the triad should be viewed as an admonition of potential behaviour that could cause harm to others in the future. In a slight comparison, the Trauma Control Model (Hickey, 2002) masks personality traits as a contributing factor to determining homicidal behaviour. Hickey (2002) deduces that researchers overlook the main drives underpinning the behaviour and explains that ‘pre-dispositional factors may influence

5 the serial homicidal process, but such factors do not drive the process.’ With both models in mind we can contemplate factors that could help us predict intentions to commit homicidal behaviour and the likelihood of this happening amongst those exposed to certain factors, however further exploration into the actual process of the behaviour would need to be done.

Burgess, Hartman, Ressler, Douglas and McCormack (1986) proposed the motivational model of sexual homicide. The model comprises of five components that all interact with each other, with the consequence of these interactions being homicidal behaviour. The five components are as follows; ‘ineffective social environment, formative events, critical personal traits and cognitive mapping process, action toward others and self, and feedback filter.’ If we can understand and predict one’s motives, we are more likely to be able to predict their behaviour, so with regards to homicide prediction, models surrounding motives must be considered. It is of common knowledge that motive exploration is a key line of enquiry in the majority of homicide cases, so any methodological findings concerning making this more accurate and easy process would be considered. It is also important to ensure the link between risk factors and motives is cogitated, for example if an individual has been abused as a child, their motives for homicidal behaviour could be as ‘revenge’, either directly to whoever abused them or indirectly toward society for letting it happen.

3. Models and Theories Surrounding Schizophrenia

In 2009, the ‘Annual Report of the National Confidential Inquiry into Suicide and Homicide by People with Mental Illness’ was released and highlighted an increase in those suffering with schizophrenia committing homicides (Singh, 2009). Similarly Meehan et al. (2006) stated, of the 1,594 people convicted of homicide between 1996- 1999, 85% had schizophrenia, suggesting the prevalence of schizophrenia in perpetrators convicted of homicide was greater than those in society (.3 to .9 per 1,000). Eronen et al. (1996) explains how there is little research surrounding prevalence of schizophrenia in perpetrators of homicide. The two do however share factors, for example the average age in which schizophrenia is most apparent in the population is 18-35 years, similarly the average age of homicide perpetrators is 18-24 years (UNDOC).

6 In order for us to be able to predict behaviour caused by schizophrenia, we must be able to understand how schizophrenia develops and whether the precipitating factors have any part to play in the consequential behaviour. There are many theories surrounding schizophrenia, biological, psychological and socio-cultural. The biological theories incorporate genetic factors and the dopamine hypothesis; the genetics of schizophrenia suggest that schizophrenia develops due to genes inherited. The dopamine hypothesis deduces that schizophrenics have an excess of D2 receptors, resulting in increased firing of neurons. An ample amount of research surrounds the biological theories, including twin and adoption studies (Joseph, 2004; Tienari et al. 2000), all of which suggest some biological involvement, but none suggest complete biological causation with regards to schizophrenia. The psychological theories suggest that schizophrenia develops due to an individual trying to re-establish control of their ego, having lost it in infantile life due to regression as a consequence of parental behaviour. Freud (1924) explained how the symptoms of schizophrenia acted as ways to regain the previously ‘lost’ control. The cognitive explanation, considers the biological approach as a root cause for the underlying symptoms, but goes onto to explain that the surface symptoms such as apathy, delusions and hallucinations are a result of the individual rejecting the feedback from those around them. There is no confirming evidence to solely rely on the psychological theories surrounding schizophrenia, for example parental studies of those with schizophrenia (Oltmanns et al. 1978) do show that parents behave differently if their child has schizophrenia, compared to parents who don’t have a suffering offspring. However the causation of this obscure behaviour may be as a result of the illness in their offspring rather than a causing factor. Finally socio-cultural theories such as Furnham & Bower’s (1992) social model are considered, they assume schizophrenia is triggered by life events, broken relationships and labeling of individuals whom don’t sit within the social norms, these factors however, proving to be more difficult to quantitatively measure and very much rely on self-report.

Taking all three areas of theory into account, prediction of schizophrenia is possible, but is spanned across a plethora of factors, some of which a person may possess, but the illness may not actually become apparent. Equally illness may appear as a result of numerous factors. The question we need to ask is do these factors overlap with any factors believed to be a risk of homicidal behaviour?

7 4. Can we forecast a schizophrenic’s likelihood of committing homicide?

Eronen et al. (1996) explained there is little research surrounding the prevalence of schizophrenics amongst those who have committed homicide. There have, however, been a number of studies regarding individuals with schizophrenia who have committed homicide and the care they receive post conviction (Ritchie et al. 1994). Brennan et al. (2000) stated ‘there is a weak but definite association between schizophrenia and violence.’ Further to their research, Eronen et al. (1996) found that the majority of views suggest schizophrenics are no more likely to commit homicide compared to any other person, but they do highlight flaws in methodologies of several previous studies. They established that over the last 30 years, Finnish detectives have managed to elucidate 97% of homicide cases after those involved were put through strategic forensic examination. 1,423 suspects were put through examination and 93 of them showed to have symptoms of schizophrenia. It was found that schizophrenics both male and female were more likely to commit homicide at a tenfold rate, compared to the general population. This study demonstrated a prevalence (0.65%) close to that of the world average, thus suggesting the results were more valid than not. However it is not an inevitable outcome of having the mental illness, as the prevalence was not 100%. Perhaps it is more a combination of schizophrenia and the risk factors aforementioned.

Fazel et al. (2009) ‘established schizophrenia and other psychoses are associated with violence and violent offending, particularly homicide’. They concluded however that the majority of the risk linked to violent behaviour (inclusive of homicide) is arbitrated by co-morbidity with substance abuse. This brings to attention two points of consideration; causality of violent behaviour may be linked to substance abuse, more so than schizophrenia and interventions for substance abuse could not only reduce mental illness, but also reduce homicide rates. Beaudoin et al. (1993) explored the links between schizophrenics, homicide and substance abuse. They experimented with participants whom had been found not guilty due to reasons of insanity (NGRI), participants whim were convicted of homicide and also suffered from schizophrenia and participants convicted of homicide who appeared to have no mental disorders. They found the latter group to be more likely to have a substance or dependency problem compared to NGRI’s and those convicted of homicide were more likely to have committed the crime under the influence, mainly because the NGRI’s were most likely to

8 commit their crime in an ‘acute phase of mental illness’. This demonstrating that substance abuse is an influential factor in homicidal behaviour and schizophrenics who commit homicide.

Being able to predict that a person with schizophrenia will kill a specific other, at a certain time, in a certain place is very unlikely, due to specificity and the fact that homicide is not always a planned event. It is possible however to consider the three factors: victim, time and place as ways of increasing prediction accuracy. Do these differ amongst schizophrenics compared to general population? Are there any specific patterns seen amongst schizophrenic cases that make it easier to predict the likelihood they will commit homicide? An example of the three factors intertwining is made clear by Fox & Levin (1998) who explain that a typical serial killer is a male, between the age of 25-35 whose target victim is a stranger and usually commits the crime near his workplace or home.

a) The type of homicide

There are different categories of homicide; single, serial, mass and spree (Fox & Levin, 1998). It is important to take into account how these types differ, as accuracy of prediction will only occur if we know exactly what it is we are expecting to happen. It is an overarching factor that should be considered as working out methods and the best ways to predict whether homicide is likely to occur. The type of homicide has been found to not only relate to the victim of the behaviour, but also the location in which it occurred or the body was found. Case studies of various homicide perpetrators highlight the variance seen between each and every cases, Ted Bundy was a well-known organised serial killer in the 1970’s, Juan Corona a well-known disorganized serial killer.

b) The victim

If we can establish who the victims of homicide may be, we are more likely to be able to predict the behaviour. It is of common knowledge amongst forensic psychologists that serial murderers tend to target strangers, whereas single homicide victims are often known to their killers. Putkonen, Joyal, Paavola and Tiihonen (2004) explain that approximately 50-60% of homicide victims by those with a mental illness (e.g. schizophrenia) are relatives; only 12-16% of victims had no connection with their killers. It was however established that the likelihood of victims being complete

9 strangers increased if the mentally ill perpetrator lived away from relatives and had a problem with regards to substance or alcohol abuse. It was concluded that overall ‘family members, acquaintances, friends or health care providers are more likely to be targeted by schizophrenics.’ The addition of acquaintances and health care providers opens up the victim base somewhat, and although it reduces the likelihood of a member of the general public being a victim, with regards to prediction it doesn’t significantly impact accuracy attempts.

Nielssen et al. (2011) carried out a meta-analysis and explored the types of homicides being committed by schizophrenic individuals. They found that homicide involving victims that are unknown to the perpetrator are very infrequent if the perpetrator suffers from psychosis and even less common if they have received treatment in the form of antipsychotics for the illness. They conclude that failure to establish a pattern or significant correlation between characteristics of stranger homicide ‘suggests that risk assessment of patients known to have a psychotic illness will be of little assistance in the prevention of stranger homicides.’

c) The location

Location of where a homicide will take place is another factor that must be considered when looking to predict homicidal behaviour. Steadman et al. (1998) stated that perpetrators whom suffer with mental illness usually commit the homicide offence in public places, rather than behind closed doors or in remote locations. This does suggest that homicides carried out by mentally ill individuals (e.g. schizophrenics) may not necessarily be planned. We can assume that in order to reduce the chance of being convicted of a crime, carrying out the crime in a remote or private location is one way of doing this. Hickey (1997) deduced that only 34% of homicide cases were found to be committed far away from the perpetrators home, where as 66% were in specific locations or within a similar ‘general location’. Earlier findings by Hickey (1991) with regards to serial killers suggested there were three main types of location bands; ‘locals’, ‘place specific’ and ‘travellers’. The definitions however are somewhat flawed with regards to Hickey’s (1991) study, mainly because there were no specified quantative distances for each category, making it difficult to measure. Holmes & Holmes (1996) subcatergorised killers into ‘geographically stable’ and ‘geographically transient’ further explaining that some killers commit their crimes in the same locations over and over,

10 where as others switch between locations, neither of them suggesting that there is no pattern. Not much research has been done on spiral killing, but a BBC drama ‘The Bletchley Circle’ based on a group of female detectives aiming to uncover a serial killer, identified a ‘spiral killing’ – it is possible spiral killing is an indirect way of demonstrating complacency. As the individual kills more people and seemingly ‘gets away with it’ he/she will move further and further away from their ‘comfort zone’, whilst maintaining a line to their past killings, creating a spiral like pattern in their criminal activity.

We can look at homicide locations in terms of rational choice theory. Lundrigan & Canter (2001) explained how a serial killer could travel further enough away to commit the offence or bury the body in order to feel some sense of satisfaction, which would be the benefit to them, but went onto explain that the cost would occur from them travelling further away and becoming apprehensive about not getting convicted – something displayed in the spiral killing theory. Much of the research with regards to location of homicides is concerning serial killers, as they repeat the crime so patterns are therefore visible and apparent, or non apparent. They concluded that the places, in which serial killers chose to leave/bury their victims bodies, reflect the fundamental logic of the choices that lead to their homicidal behaviour.

5. Practical implications of being able to forecast homicide in schizophrenic people

If we are able to predict the likelihood of a schizophrenic person committing homicide, not only can effective preventions be implemented, but also appropriate care and post- sentencing care can be provided. The ethical problems surrounding this however, cause much to be questioned. It has been highlighted that patterns can be seen in types of homicide, victims of those who perpetrate and locations of where they occur, if predictions can be made based on these patterns, then we are one step closer to being able to predict likelihood of homicide in those with schizophrenia. Further research is needed into the comparisons between homicide perpetrators and homicide perpetrators with schizophrenia, in order for us to establish whether the same patterns can be seen.

Rossmo (1995) highlighted that ‘crime locations of an individual can be used to create a

11 probability surface’ - the higher the probability, the greater the chance that the offender will commit the homicide near his/her home. Using this and appropriate risk factors we can establish the likelihood of where a homicide by a schizophrenic person may occur. Implications could then involve more specified treatments for those with schizophrenia to target the highly correlated risk factors.

Due to the sex offender act (2003) being introduced police forces can now view sex offenders in local areas, it has been proposed that any person involved in violent criminal acts should also be put on some kind of register, in which neighbours and local residents should have access too. Not only will this allow greater caution to be taken, but may also help identify patterns of where dangerous people live and whether there environment has any effect on the likelihood of them committing homicide. The question now sits as to whether schizophrenics should be placed on a register; many would argue no as there is not enough evidence to say that schizophrenia is a primary factor in homicidal behaviour. However could a compromise be made in which those who have schizophrenia and have been convicted of violent crime are placed on a register? Evidence suggests that even though not a standalone factor, schizophrenics are more likely to commit a homicide compared to a member of the general population.

Unlike in the US where the sex offender and violent crime mapping is visible to all, in the UK it is only available to the police force, HM prison staff and medical staff in certain cases. Schizophrenic individuals will have their diagnosis on medical records, but should this be more widely accessible so links can be made, that could lead to more appropriate intervention?

6. Conclusion

Predicting homicide can be done in a stepwise manner – catergorisation of subgroups within homicide (e.g. type, victim and location), identification of patterns within these subgroups, predictions made based on patterns within each subgroup. Similarly risk factors could be used to help identify possible patterns of an individual’s behaviour, including those with schizophrenia. Fox & Levin (1998) state that future research should look to include more information surrounding comparison groups and explore life-cycle factors that have occurred post childhood that may map out patterns across multiple killers.

12 As we saw from Beaudoin et al.’s (1993) research, substance abuse and dependency are highly influential factors in homicidal behaviour and complete a triad of highly risky persons in society when combined with schizophrenia. Therefore interventions relating to substance abuse should be further invested in, especially in those with mental illnesses. It can be concluded that regular monitoring of symptoms may help to ascertain an increased risk of violent behaviour, inclusive of homicide. Contrary to knowledge of this, care of those with mental illnesses such as schizophrenia should be adapted to cater for needs of individuals, whilst ensuring to reduce the risk of homicidal behaviour.

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16 Weatherby, G. A., Buller, D. M. and McGinnis, K. (2009) The Buller-McGinnis Model of Serial Homicidal Behavior: An Integrated Approach. The Journal of Criminology, Criminal Justice and Education. Vol. 3, Issue. 1.

Websites:

WHO (2014) World Health Organisation: http://www.who.int/research/en/

Mental Health Today: http://www.mentalhealthtoday.co.uk/mht/default.aspx

UNODC: https://www.unodc.org

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