Forensic psychology involves the application of psychological knowledge, theory and skills to the understanding and functioning of the legal and criminal justice system. Among its many functions, is to cover areas related to the assessment and treatment of offenders. Also involved, is the assessment and treatment of mentally abnormal offenders, as well as the legal aspects of psychiatry. This includes knowledge of the law relating to psychiatric practice and issues of criminal responsibility. One of the areas that this discipline is currently addressing is violence in the mentally disordered.
This essay will outline the role and contribution of forensic psychology in one particular set of mental disorders, namely psychoses and their relation to violence. If the tabloid press and many movies were anything to go by, one would assume that anyone with a psychotic disorder was crazed murderer, with evil voices telling them to kill innocent people. This is of course a sensationalised view, and in actual fact, although many people believe that those with mental disorders are more likely to commit violent acts, results of research which indicates this are subject to conflicting interpretations, due to methodological, and other, issues.
Some question forensic psychologists have still and are currently been trying to clarify in this area are; whether or not those with major mental disorders are any more likely to commit violent acts than those without, if psychosis is a risk factor, and how to predict which individuals in the mentally disordered population are at more at risk of becoming violent. In a study of mentally disordered patients by Stedman et al (1998) comparisons were made with the general population, this yielded results which indicated that the abuse of substances was a key factor in violence in the mentally disordered sample.
When he compared these results to the general population there was no distinction between prevalence of violence among the general population and the patents where substance abuse was not involved. Where there was substance abuse however, there was a marked increase in violence in both samples, with patients showing more violence in the weeks following discharge from psychiatric care. Most of the violence was shown to be directed at family members and known people. This refutes the notion that patents with mental disorders are any more of a danger to society in general than others who commit violent crimes.
Bonta, Law and Hanson (1998) also proposed from their findings, that risk factors for the mentally ill committing violent crimes are very similar to those for the general population. One of the next issues in this area is in the classification of the types of mental disorder. The disorders that fall into the category of psychotic disorders are schizophrenia, bi-polar disorder (formerly known as manic depression) schizoaffective disorder, schizophreniform disorder and substance induced psychosis.
The way in which the psychiatrists and psychologists define mental disorders differs greatly, and this in itself can pose a problem for the individual with a mental disorder. Psychiatric diagnosis seeks to classify individuals with mental disorders, whereas much research in psychology points to a need to remove such labels on the basis that it can serve as not much more than to stigmatise individuals (Pilgrim, 2000). Most of the classification is based on observation and expert opinion, and little of it is based on scientific, hypothesis-based research.
In order to review the literature on violence and psychotic disorders, it is necessary to outline the symptoms. Using the classification system of the Diagnostic and Statistical Manual of the American Psychiatric Association (DSM), mental illness is categorised into five broad areas of psychiatric diagnosis. The disorders mentioned above, fall in to DSM-IV. The presence of two or more of the following symptoms over a period of a month would indicate a diagnosis of schizophrenia: delusions, hallucinations disorganised speech, periods of catatonia or disorganisation, lack of affect, and a lack of ability to persist in goal-directed activity.
The presence of some of these symptoms for six months, with the presence of severe symptoms for at least one month, and impairment in work, intellectual performance, personal care and relationships would be necessary criteria for diagnosis. Those with other mentioned psychoses experience the symptoms of schizophrenia some also with mania or depression, and in the case of bi-polar disorder, manic depression. Due to the varying definitions, a certain degree of overlap is inevitable.
This is one of the major confounding factors in the study of psychoses and violence. Some of the forensic research, concerning the epidemiology of violence in those with psychoses, concentrates on delusions and hallucinations (which will be looked at respectively): symptoms originally thought to increase the risk of violence. Delusions come in many forms, such as thought broadcasting and insertion, grandiose delusions and delusions of being controlled. Persecutory delusions however seem to be those which have generated the most interest to date.
In a review of the previous literature on delusions and violence, Bjorkly (2002) pointed out that despite the fact that more and more research has shown evidence to associate delusions and an increased risk of violence, this is not sufficient to explain the role of delusions, as they are present in the non-violent population of psychiatric patients too. In this review, Bjorkly looked not only at a possible between the risk of violence and delusions, but also to identify if there are any particular features of delusions that may increase that risk.
He looked at 26 studies that addressed one or more of the following issues: delusions threat and internal control override (or TCO, which is the loss of control in the presence of a threat) and delusional distress. He found that two thirds of the studies were retrospective, the results of which are now considered questionable due to the methodological issue of the reliability (or lack thereof) of the measures used. In more recent studies, improved methodology has refined this problem, however this has proved to make comparative analyses difficult.
It was found that studies by Kunst (1999), Freeman and Garrety (1999) and Wessley, Buchanan, Reed, Cutting, Everitt, Garety and Taylor (1993) that delusions of persecution were those most likely to be acted upon or involved in violent acts. These particular delusions seem to be differentiated by the presence of high levels of worry. Link, Monahan, Stueve and Cullen (1994) found evidence to suggest that other psychotic symptoms were unrelated to violence when measures to control TCO symptoms were put in place.
This indicated that TCO may good predictor of violence and also provides some clarification for the previous delusion and violence association. It hardly seems surprising that if one feels that they are going to be harmed or singled out high levels of worry and distress would accompany that this. This may leave the individuals feeling as though they have no choice but to resort to violence under the circumstances in order to eliminate, or protect themselves from the perceived threat.
This was however largely overlooked until recently. The role of delusional distress in violence was examined by several studies (Buchanan, 1997; Freeman et al, 1998; Appelbaum et al 2000) highlighting that it may be the presence of other (distress causing) factors which exacerbate in the case of persecutory delusions. These being: high anxiety levels, anger, low self-esteem respectively. Silva et al (1996) propose that the level of fear or anger guided at the delusional phenomenon may be a good predictor of dangerousness.
Bjorkly subsequently went on to examine the role of hallucinations on violence. Although some claim to have found evidence to associate the two, there has been equally compelling evidence to the contrary. One of the main criticisms is again the issue of the reliability of the methodology used. Many studies had overlooked important factors for ascertaining the presence of command hallucinations. Which goes some of the way to explaining the contradictory findings. Also confounding, was the lack of inclusion of some demographic information.
This made it difficult for Bjorkly to interpret some of the results from the studies. The phenomena studied in this review were papers concerning auditory hallucinations, and violent and non-violent command hallucinations. Contrary to popular belief, Beck-Sander, Birchwood and Chadwick (1997) found that patients were more likely to comply with kind and friendly voices. It was however the studies that examined the effects of delusions and hallucinations occurring together that provided interesting results.
It was found that there was more likelihood of compliance with hallucinatory commands if there was evidence to support the patient’s delusions (Swanson, Borum, Swatz and Monahan, 1996). In the absence of delusions however, there seemed to be less chance of violence being triggered (Taylor et al, 1998). To summarise the literature to date then, it would seem that in the presence of psychoses, there is evidence to suggest an association between violence and delusions of persecution.
There is also some evidence for the increase of acting on persecutory delusions in the presence of emotional distress, and that a possible risk factor is TCO. Furthermore, there is a lack of evidence to support a link between auditory command hallucinations and violence. There is however a little evidence to suggest an interaction between delusions and hallucinations increasing the risk of violent behaviour. This evidence though is inconclusive due to the lack of studies found examining this possibility.
This is thought to be due perhaps, to many taking the association between hallucinations and violence for granted. In light of the evidence from the few studies found in this area, future research on this is imperative. Forensic psychology has thus far contributed greatly to the understanding of the factors that may predict violence in individuals with psychoses in part by questioning the methods previously used in order that current theory is furnished with reliable information rather than biased or inaccurate information.
This however must be studied further to gain an understanding of the combinations of factors associated with psychoses that increase the risk of acts of violence being committed. Also to be considered in the future is the way in which risk in psychotic patients is perceived, with the correct care or incorrect care, symptoms factors, which aggravate the risk of violent behaviour may manifest themselves or diminish thus risk must be seen as something which is subject to change. This indicates the need for regular and repeated assessment.
It is now becoming increasingly apparent that it is not enough to single out an individual symptom or set of symptoms as predictors of violence, but to explore in more depth and draw from more domains, the other factors which interplay with these symptoms to produce or increase the risk of violent behaviour. This will not only assist forensic psychologists and psychiatrists in a their recommendations in the assessment and treatment of the forensic population with psychoses, but protect them from prejudice and ensure they receive the treatment necessary to ensure their comfort and reduce the risk of recidivism.