13 May 2015
Perpetrators of Human Violence
Professor Gwen Adshead
In my first lecture, I discussed the causes of human violence and invited the audience to consider the complexity of human violence; and the role of violence as a medium for communicating a dreadful message to others. I discussed risk factors for violence at the macro-level (gender role stereotypes, political attitudes to inequality, crude utilitarian approaches to value) and at the micro-level (age, sex and ethnicity). In this lecture, I want to stay with the level of the individual, and focus on the perpetrators of violence. For this discussion, I will focus on what I know best: those who commit acts of criminal violence in England and Wales, based on the most recent data ( Smith et al, 2012).
Even allowing for under-reporting, violence is an unusual form of criminal behaviour; accounting for 20% of criminal convictions. Naturally however, violence perpetrators make up the bulk of prisoners serving sentences; generally, the more serious the violence, the lengthier the sentence.
The type of violence that is most commonly reported and results in conviction is usually violence between males that results in death or serious injury. Violence between drunken young men is the commonest form of violence reported to the police; followed closely by reports of intimate partner violence: mainly male to female but also female to male and some same-sex. Sexual violence is said to be substantially under-reported, the percentage of allegations that eventually go to trial is small: only 1-2%. The rate of convictions for rape and indecent assault has remained very similar for over 20 years. A likely influence on the pursuit of prosecutions is stereotypes about what constitute a 'real' rape (Adler 1987); women who do not 'fit' the picture of a rape victim may find that their experience is not taken seriously as rape. The situation for men who are raped is even graver; there is almost no data on this phenomenon because men who are raped rarely report, especially those men who are raped in prison.
Probably the least reported violence is physical violence to children, which may affect as much as 20% of the population (based on historical reports by adults), and which results in death in 10% of cases. Young children under the age of 1 are the most likely people to be victims of homicide, and the vast majority of perpetrators are their parents or other adults in a parenting role. The lack of convictions for child abuse and cruelty is in contrast to the numbers of children taken into care for abuse and neglect: In 2014, about 45,000 children in England and Wales were taken into care because of concerns about abuse and neglect by their parents. Even if we assume that not all abuse and neglect is 'violent', it is known that fatal child abuse always begins with abuse that is not violent: the distinction is in degree, not nature.
What I suggest is that the nature of violence is intimately related to its communicatory function: perpetrators are communicating a message to those they hurt. The message naturally varies from person to person, and context to context: but there is a common element (I suggest) which is that the victim is meant to understand that they do not matter as a person. The violence perpetrator, (for a moment at least), exults in their power over the person who in their eyes has dismissed them, frightened them, insulted them or shamed them. Even for those perpetrators who are violent out of fear or perceived threat (what is sometimes called 'reactive violence’ (Dodge 1991), there is a moment of triumph and excitement in damaging the person they fear. For those who are proactively violent, the perpetration of violence is satisfying in itself, as well as achieving an end. The violence has sent a message to the victim; the job is done.
What type of violence are we concerned about? This may seem an odd question; a stable democracy should be concerned about the prevention of all types of violence and the protection of the public from all violence perpetrators. However, like many other societies, England and Wales take homicide most seriously. Convictions for murder result in automatic life sentences, but other offences can also attract life sentence. Whole life sentences are usually reserved for multiple or especially heinous murders. But I suggest we should be much more concerned about violence to children, because of the extensive evidence that childhood adversity is a significant risk factor for a huge range of bad adult outcomes: including violence to others. In my previous talk, I referred to the evidence from the Kaiser Permanente studies of HMO users, which examined the link between childhood adversity and heath care service usage (Felitti et al 1998). The more childhood adversity people were exposed to, the more likely they were to suffer poor physical and mental health in adulthood. Similar studies have now been carried out with offender populations; and found that exposure to childhood adversity also increases the risk of conviction for violent crime, including sex offending (Duke et al 2010; Levenson, 2014).
Who are these people?
As I said in my first lecture, the overwhelming majority of violence perpetrators are male. Quite why this should be is not known: speculation includes attention to toxic gender role stereotypes of masculinity; the vulnerability of the Y chromosome to environmental damage; and the extent of physical violence suffered by boys in childhood and teenage years. Any analysis must account for the evidence that most possessors of the Y chromosome are not violent and never will be: it is only a sub-group of males who are violent. Most of these have started committing acts of violence in their teenage years; and persist into adulthood (Moffitt 1993). To start a violent career in one's 30s and 40s is vanishingly rare.
Young men are therefore the sub-group of men most at risk of violence. Their risk increases if they misuse alcohol and illicit drugs, because ingestion of drugs and alcohol decreases judgement and discernment, and also distorts thinking and perceptions. Violence risk is also increased if young men have persistent antisocial attitudes that make them ready to break the criminal law; most young men who are violent have broken many other criminal laws before they act violently. It is their attitude to the rules that connect people that makes them antisocial; even those young men who get into groups to behave violently. As the UN Global study of homicide noted, fatal violence is associated with general crime perpetration in about 40% of cases.
One personality feature that makes it easier to commit acts of violence is the tendency to act without thinking; what is sometimes called 'impulsivity'. This tendency may also be understood as an inability to hold onto craving or inhibit emotional responses. It is a complex trait, which is known to have a neuro-cognitive basis; one consequence of frontal brain injuries is impulsivity, and loss of concern for social norms (Scarpa & Raine 1997)
The difficulty with focussing on impulsivity as a risk factor for violence is that it does not account for those acts of violence that involve planning and forethought. Many sex offenders plan their violence carefully; especially those who attack children. Most armed robbery and intimate partner violence is not impulsive, but no-one would suggest that it is not violent. Impulsivity is also hard to assess in the context of misuse of substances that are known to lead to disinhibition of activity at a neuronal level: alcohol being the most obvious. It is thought that alcohol plays a part in 80% of violent assaults, and any illegal drug that increases arousal, agitation or paranoid feelings will also increase the risk of violence.
Brains and minds
There has been considerable interest in whether violence perpetrators have brains and/or personalities that differ from the general population. A quick roam around the internet will find hundreds of images, books, presentations and papers entitled 'The Violent Mind' or 'The Violent Brain'. It makes sense at one level to focus attention on the individual perpetrator in this way; such perpetrators are both scary and unusual, and understanding more about their decision making might be helpful in violence prevention.
Hence there are many brain studies of violence perpetrators (e.g Yang & Raine 2009). These usually take the form of comparison studies between a group of violence perpetrators and a group of allegedly non-violent others. Research methodologists will immediately be wondering about the selection of both the violence perpetrators and the comparison group; and also about how one ensures that the comparison group is not violent. There are different question to be asked here: does one compare violent criminals with non-violent criminals? This might allow us to study people who are do not escalate from criminality to violence. Or would it be better to compare violent criminals with non-offenders? The problem here is that it is known already that violence perpetrators are a small sub-group of the community; the large population size difference may eradicate any small significant differences statistically. Or would it better to compare different types of violence perpetrators: for example, comparing reactive versus proactive or comparing sexual with non-sexual violence?
This research is also complicated by the methodology of brain scanning. We know that there are no brain areas that correspond to human actions or behaviours; rather, the brain is dynamically active all the time with different neural networks firing and connecting in different patterns across different parts of the brain at all times. We know that the neural networks that are most active when we make complex decisions about ourselves and other people involve the medial pre-frontal cortex, the amygdala, the hippocampus and the anterior cingulate cortex. Any study that involves a complex human thought, and especially thought about thought, involves these circuits.
So if we want to study the decision making behind acts of violence, we know where to look. It is not a surprise to find different patterns of neural activity in the brains of convicted violence perpetrators: We know they must have different brains because they took a decision which is so unusual compared to the rest of us; even compared to other criminals. Further, as we have already seen just in relation to homicide, the thinking behind a violent act is not singular and homogenous. Some homicide is about achieving criminal dominance, some is about terrorising others, and some is a desperate act of love and hate mixed into one: a study that compared neural activation in these three groups would be of interest.
What we need to understand is the decision making process behind an act of serious violence; which undoubtedly involves the brain as most complex decisions do. It may be that there are patterns of brain activity that make the decision to act violently more or less likely; for example, it is known that brain injuries to the medial prefrontal cortex (mPFC)can result in impulsivity that makes violence more likely. Studies by Raine et al (2001) and Kolla et al (2014) have found evidence that indicates that physical abuse in childhood may affect neural development in different ways in different types of violence perpetrators. Similar questions can be raised in relation to genetic influences: there are genetic variations that affect the levels of neuro-chemicals in the brain at a synaptic level, which may influence sympathetic arousal and impulse control. They may increase the risk that someone with a violent thought will act on it; they do not generate the violent thoughts and intentions themselves.
Where do violent thoughts come from?
So we come back to where the violent thoughts come from in the first place; how they are generated and in what circumstance. As I tried to suggest in my first lecture, these violent intentions seem to arise from a complex interaction of environmental/ social risk, and individual psychological motivations and belief. I utilised the model of the bicycle lock (Yakeley and Adshead, 2013) to illustrate the multi-factorial nature of interpersonal violence, arguing that there are general risk factors that are common to all violence perpetrators ( such as being male and misusing alcohol) and risk factors that are specific and idiosyncratic to that perpetrator: especially mental illness and/or relationship breakdown. A study in 2009 by Elbogen and Johnson found that substance misuse was a massive predictor of violence perpetration; but also that the breakdown of an emotional relationship (as measured by reported divorce) was also a powerful predictor.
This brings us to the role of attachment in violence perpetration. Attachment theory is a theory of how minds and brain develop and manage stress across the life span. A key concept in attachment theory is that our closes attachments help regulate our stress levels, and our most difficult feelings: distress, anger, fear. The loss of a close relationship can therefore lead to disorganisation of the mind: sufficient to make people to stop thinking clearly and rationally, especially in people whose mental function is already not so good. Two recent studies (Maguire et al, 2014; Kaplow et al 2014) found that the sudden loss of a loved person increases the risk of developing mental illness, especially depression and manic episodes.
Is there any evidence of relational loss being a risk factor for violence perpetration? Theoretically, this is possible because it is known that anger is a common affect after human loss; possibly because it is preferable to feel angry rather than sad and/or hopeless (Bowlby 1982). If we look at the victims of the most severe human violence (homicide) we find that partners and especially ex-partners are most likely to be victims of homicide. The loss of a close attachment disorganises the perpetrator's mind: and if other risk factors for violence are present, then the loss of the attachment may well be the last number that 'unlocks' the violence.
This phenomenon is well known to those who work with IPV perpetrators. In some cases (though not all) the risk of serious violence increases if the woman tries to leave the relationship. Interestingly, this phenomenon is also apparent in rape cases, where the most common rape perpetrator is the ex-partner of the victim, presumably exacting revenge of being rejected.
The point here is that relationships matter in the analysis of violence, and to the perpetrators of violence. Violence perpetrators rarely attack strangers; the chance of being raped or fatally killed by someone not known to you is very small. Relational factors may also explain the small contribution of mental illness to violence risk; some mental illnesses result in paranoid states of mind, which make sufferers believe that other people have some bizarre connection to them, usually involving hostile intention. These beliefs, especially if they involve the belief that others are interfering in some way with your mind, can tragically lead to serious reactive violence by a mentally ill person to a strangers. However, this is statistically incredibly rare; and generally the most likely victims of violence by the mentally ill are family members and carers. Finally, the risk of children from strangers is infinitesimal: most children are abused, attacked and or killed by people who are very well known to them. Attachments, and the perpetrator’s view of their attachments, seem to be a crucial risk factor for violence (Ogilvie et al 2014).
Are all violence perpetrators the same?
Sociologists have long argued that violence is a communication, especially a communication by the down trodden and oppressed. How are we to compare the violence of the ANC in its struggle against apartheid with the violence of man who kills his wife under the influence of a paranoid psychosis; and does it make sense to do so? Cultural beliefs about the acceptability of violence make violence more likely; this is clear in relation to intimate partner violence, where individual psychology interacts with cultural beliefs about wives and partners as possessions (Dutton 1994). Dutton's work makes it clear that violence is complex interaction of multiple factors, and cannot be reduced to a single explanation.
Similarly, there are studies of cultures that are described as 'rape prone' (Sanday 1981) i.e. that support beliefs that make rape and other forms of sexual violence possible; per contra, there are cultures where violence towards the vulnerable is not tolerated, and rape convictions are less frequent. It is important to note in this context, sexual violence is violence that involves an attack on, or the use of, the genitals; it has nothing to do with the erotic activity known as sex and everything to do with shaming and belittling the victim. The message in sexual violence is (quite literally) 'Fuck you'.
Also in the context of the social context of violence, I like to consider the minds and brains of the men who attended the Wannsee Conference in January 1941; and speculate on how they came to develop the idea that it was a good idea to eliminate out a sub-group of the citizenry when they were in the middle of a war. I note too that they took pains to make it 'lawful', so they could convince themselves that it was right; I also note that they tried to stop the minutes of the meeting being preserved. Nothing impulsive here; only an example of what UNDOC called violence to people just because of who they are, and to send a message of terror.
It has been argued that the Holocaust would not have happened without the influence of one man; a man whose mental health and psychology has been extensively studied. We come back then to the influence of individual psychology on acts of violence; and the question of whether there are a sub-group of people on the planet who are much more interested in violence than the rest of us. No discussion of this subject is complete with reference to the work of Professor Robert Hare (1999), who has spent a lifetime studying people who have been extremely violent. He believes that there is a sub-group of men and women in the community, called 'psychopaths', who are unusually committed to violence and cruelty. He argues that this sub-group of violent offenders are not only impulsive and antisocial, but emotionally cut-off and deliberately cruel to others. He takes the view that they lack the capacity to care about human distress; and may even enjoy it or have contempt for it.
Professor Hare is a world expert on psychopaths, and how to study them. He devised a checklist to help law enforcement agents and prisons work out if criminals they were supervising were psychopathic or just 'normally' violent. Professor Hare has also teasingly suggested that it is possible to be psychopathic without being violent; and that the predatory and anti-human attitudes that he describes in psychopaths can also be found in world leaders and corporate raiders. His work has generated debate in the press, books and movies; as well as academic research looking for signs of psychopathy in college students, children and bankers.
Psychopathy and gender: risky states of mind
Psychopathy is a huge subject; and I cannot do it justice here. It seems clear that psychopathic states of mind can significantly increase the risk of violence perpetration; but it also seems clear that the vast majority of violence perpetrators do not meet criteria for psychopathy. Only a sub-group of violent individuals meet criteria for psychopathy; Hare himself found that less than a third of violence perpetrators show this complex mental personality constellation i.e. the majority of violent offenders do not.
There has been a lot of interest in whether there are non-violent psychopaths who run businesses and countries in cruel and unusual ways. Even if this were the case, these men (and possibly women?) are not physically violent, and the danger they pose is different. We may wonder what the concept of non- violent psychopathy is really describing: whether we are trying to address inhuman and objectifying attitudes to people that seem to be increasingly prevalent in communities which are dominated by crude accounts of utility and costs benefit; and where people are commodified in the name of free market economics.
However, psychopathy does raise two other interesting issues. First, where do these guys come from? Do they arrive on the planet with an absence of humanity wired in? Or do they become psychopathic in response to events and environmental stimuli? Or (more likely) there is more than one type of psychopath, and what they have in common is a readiness to be cruel and to ignore distress; to be predatory as opposed to being affiliative. Is it possible that we get more psychopaths if we have social communities and attitudes that either overtly or covertly supports their world view? This must be worth studying.
The second issue is the issue of sex differences in violence, and a question about female psychopaths. Biological sex seems to be a major risk factor for violence: or is it? Some have argued that it is not the Y chromosome which is the problem, but a toxic masculinity, which acts a social vice on the gender role beliefs and expectations of young men and women alike. Gender role expectations may interact with individual vulnerability to generate a state of mind in which violence is normalised and potential victims are regarded as 'fair game'. Some traditional accounts of masculinity emphasise being tough and un-empathic towards one's own distress, and by extension to anyone else who seems weak. I described in my first lecture the work of Professor Jim Gilligan, who has argued that shame and honour based accounts of masculinity will generate a contempt for suffering and neediness that is supportive of violence prone attitudes; especially towards other men. Such toxic masculinities will contribute to the risk of all types of violence; especially sexual violence and homicide.
If a young boy is told that 'real' men eliminate anyone who appears to disrespect them, and if he comes from an insecure and adverse childhood, and lacks male contact that could provide an alternative account of masculinity; and if he uses drugs to 'big' himself up: then it seems clear how all the risk factors are in place for serious violence. What is interesting is that female perpetrators of violence are not very different to this profile: except in terms of actual numbers. Violent women form a very small sub-group of convicted and imprisoned offenders, and the numerical difference between the sexes is striking worldwide.
However, when analysed more closely, although the absolute numbers are different, the women violence perpetrators do not seem very different from the male (Putkonen et al, 2003). When women are violent, they can be violent in similar ways: they can plan, they pick on vulnerable targets, and they show attitudes that are supportive of violence. Both violent men and violent women have similar levels of experience of childhood abuse and trauma, and adult victimisation. Both male and female violence perpetrators pick on victims who are accessible, vulnerable and 'fair game' because they are seen as possessions; violent men tend to pick on younger men or women, and violent women pick on children. Most female violence perpetrators tend to be young (like their male counterparts) ; their stated motives for violence are not different ( Adshead 2011). One study comparing male and female murderers found that they were very similar, including in terms of how psychopathic they were (Weizmann-Henelius et al 2003). So the really interesting question is why there are so few female violence perpetrators; Possible explanations include that (a) it 'takes more' to make women offend, or (b) that there is something protective about having 2 X chromosomes, or (c) that the generally prosocial gender role expectations of traditional femininity act as a powerful buffer to ordinary cruelty and the wish to hurt.
Cruel and unusual attitudes: the dismissal of distress
One important feature of some psychopaths appears to be their failure to respond to stimuli that distress others i.e. they are hypo-aroused when it comes to sympathetic nervous system activation (Patrick 1994; 2012). This 'deactivation' process has also been described as a feature of insecure attachment between children and their care givers; most commonly in the context of child abuse and rejection by parents. Studies of attachment patterns in adults suggest that as many as 20% of the population have what is called a 'dismissing' attachment style, which allows people to 'turn down' the volume of distress or concern about negative events ( Bakermans Kraneburg & van Izendoorn 2009) . Such people are likely to minimise the effects on themselves of negative events, and cut short discussions of upset or neediness. Hypo activation of stress responses systems is also characteristic of this group of people, who include a small sub-group who are derogatory about neediness and vulnerability.
There is evidence that dismissing attachment style is more common in offender populations than in the general population (Ogilvie et al 2014).The dismissing style of attachment is known to be common in children who have experienced rejection and child maltreatment; and I have already alluded to the evidence that adverse childhood experience increases the risks of violence perpetration, especially in young adults. The evidence for this is robust and includes follow up studies of abused children compared to non-abused children. Studies by Professor Cathy Widom are meticulous in ensuring that the target group of children had their abuse verified by a court process, and that they were followed up well in to their third decade. Her work has shown two important things: that most children who experience abuse and neglect will not act violently as adults; but a sub-group do (Widom & Czaia, 2012). This sub-group are vulnerable in terms of their response to the abuse, and whether they have unresolved distress; it is also possible that they have genetic vulnerability also ( Widom & Brzustowicz, 2006), although there is ample evidence that you do not need to be genetically vulnerable to be psychologically damaged by regular beating or hostility from care takers. Sexual abuse does not appear to have an effect on later violence; although again, a higher proportion of sex offenders have experienced sexual abuse compared to the general population.
It is sometimes suggested that studies that look at abuse and neglect as risk factors for violence act as attempt to excuse the offender or generate sympathy for him or her. But there is nothing exculpatory about generating understanding, per se. Given that the majority of people who suffer abuse and trauma in childhood do NOT go to be violent offenders, it seems sensible to try and find out how abuse and trauma can come to have such an unusually malignant effect. Genetic interaction is one possibility; but the development of defensive contemptuous attitudes to suffering as a way of surviving abuse seems more plausible.
Another way to frame the problem is to say that violent offenders lack empathy, and that is how they come to let themselves offend. Empathy itself is a complex construct (Decety & Ickes 2011), and there is considerable debate about what might a 'normal' or reasonable amount of empathy to have; and indeed whether it is a disposition, a skill, a habit or a talent. The relationship between lack of empathy and violence is less clear cut than one might think (Vachon et al 2014); and in any event, in this context, there is a risk of post hoc, propter hoc analysis and circularity. However, empathy is related to subjectivity and the sense of self; a person who cannot reflect on their own emotional experience is unlikely to be able to reflect on others' emotions (Fonagy 1999). It may be that some violent offenders lack empathy because their sense of themselves is so fragmented and fragile; and their violent stance is a psychological stance that protects them from feeling fearful and powerless.
I want to conclude with some comments about homicide; that most violent of offences. It is often assumed that people who kill are the most violent of all offenders; and it is true that sometimes this is the case. I have met some homicide perpetrators who I would not care to be alone with for any length of time, such is their riskiness. But I have had experience of sitting for an hour at a time with 7 or 8 men who had killed; very few of whom had a previous history of violence or even criminality. They had killed in the context of a highly abnormal mental state, which was alien to them; they were all struggling to come to terms with the idea that they were 'killers'. After some initial anxiety, I came to look forward to my weekly meetings with these men, and I learnt a great deal about life after death, when you have caused the death. It is working with this group of men that taught me how complex human violence is; and how much more we have to learn.
© Professor Gwen Adshead, 2015
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