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Essay: The connection between schizophrenia and crime

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Introduction

Recently, researchers have been keen understanding the relationship between Schizophrenia, substance abuses, and violent criminal behavior. According to the majority of these latest research studies, suicide is one of the most common criminal activity associated with Schizophrenia. History of past violence is another common predictor of violent crime associated with Schizophrenia. Schizophrenia patients with a rich history of violence are likely to commit crimes such as rape and murder. Schizophrenia patient is also highly likely to engage in substance and alcohol abuse. They abuse drugs and misuse alcohol because of the mental illness that affects their ability to think and reason accurately. This means that the more the patient engages in drug and alcohol abuse, the higher the chances of committing crimes. Furthermore, it is imperative to note that Schizophrenia patient’s failure to take medication increases their chances of engaging in crime. This is mainly because, without medication, the symptoms such as hallucinations and delusions worsens. The cognitive ability of the patient is also adversely affected. As a result, they are likely to make ineffective decisions like engaging in criminal activities. The purpose of this essay is to explore the connection between Schizophrenia and Crime.

The Connection between Schizophrenia and Crime

According to an Australian study, Schizophrenia patient is three times likely to commit crimes as compared to an individual who is not suffering from any mental illness. Secondly, approximately 8.2% of Schizophrenia patients have been convicted of violent crimes. The main reason for the cognition between Schizophrenia and crime is that the disorder adversely affects the individual’s cognition (Keers et al. 2014). In normal circumstances, Schizophrenia patient acts like a normal person. However, if the disorder is not treated early, it can have tremendous implications for the patient’s life.

Schizophrenia adversely affects the patient’s cognitive ability. One of the most common symptoms of Schizophrenia is a dysfunctional way of thinking. In most cases, Schizophrenia patients are considered to be with ineffective executive functioning. In such situations, the patient has difficulty comprehending the information they are presented. As a result, they make ineffective decisions due to poor interpretation of such information. The patient’s memory is also adversely affected (Rund, 2018). This means that they are easy to forget. Schizophrenia patients also encounter challenges pay attention. For instance, when they are told that criminal activities attract punishment, they easily forget. Even if they are warned, they easily engage in criminal activities without their wish. Thus, to avoid such situations, it is imperative to encourage Schizophrenia to seek treatment as soon as possible.

Cognitive impairment as a result of the disorder can affect various aspects of the patient’s life. In most cases, Schizophrenia patients are unable to engage in normal daily activities. Some of them withdraw from the society. This is mainly because they are unable to relate and interact with others including family and friends. Thus, when faced with challenges, most of them will resort to violence and criminal activities. Lack of effective communication skills affects their ability to express themselves (Keers et al. 2014). Therefore, if untreated, they will end up engaging in criminal activities such as suicide.

Moreover, Schizophrenia patients are unable to engage in intellectual activities and tasks. Instead of reading a book, such a patient often glares on the pages without reading or concentrating. When watching, they can glare on the screen without following or understanding what is going on at all. Their ability to perceive instructions is also affected. For instance, if they are taught to be discipline, they will forget and still engage in undesirable behaviors (Fleischman et al., 2014). This is so because the disorder affects the patient’s short memory, concentration, and executive function.

Diagnosis and Treatment

The connection between Schizophrenia and crime can be disconnected by diagnosing and treating the affected patients. One of the best ways of diagnosing Schizophrenia is through a physical exam. The physical exam is mainly conducted to rule out symptoms that are not associated with Schizophrenia. Physical exam also enables the doctors to check for any other health complications that could be affecting the patient. Secondly, there are various tests and screenings that have been recommended for the diagnosis of Schizophrenia (Rund, 2018). Tests are mainly aimed at ruling out the causes of similar symptoms of Schizophrenia. On the other hand, screenings are meant to check on issues such as substance and alcohol abuse.

Furthermore, it is imperative to note that psychiatric evaluation plays a crucial role in diagnosing Schizophrenia. This is the process in which a mental health profession checks on the mental status of the patient. The most common issues that are checked include the potential for violence and crime, hallucinations, suicide, and substance abuse. The health professional can also use such opportunity to discuss the family and history of the patient (Fleischman et al., 2018). Psychiatric evaluation reveals a lot regarding the connection between Schizophrenia and crime.

In the case of treatment of Schizophrenia, antipsychotics are the most recommended medications. The primary objective of antipsychotic is to control the symptoms of this disorder by influencing the brain functioning. In essence, these medicines are focused on lowering the signs and symptoms of Schizophrenia (Silverstein et al., 2015). Antianxiety drugs and anti-depressants can also be used to treat the disorder. However, to effectively delink the connection between Schizophrenia and crime, it is vital to use psychosocial interventions.

One of the most commonly preferred psychosocial intervention is individual therapy. One of the primary objectives of this therapy is to help the patient to cope with the stress associated with the disorder. The patient is also empowered to learn about the disorder’s warning signs. In such situations, they are better placed to manage the disorder at individual levels (Silverstein et al., 2015). This means that crimes such as suicide and potential crimes are minimized. The second intervention is social skills training. The primary objective of this therapy is to improve the social skills of the patient. This means that the patient will be better placed to express themselves to friends and family (Rund, 2018). When they are stressed up, they can be easily assisted. In such situations, the potential of them engaging in violence or criminal activities are considerably reduced.

Finally, family therapies can play a crucial role in supporting Schizophrenia patients. For instance, family therapy is meant to promote and support the family of the patient. When the patient’s family is supported, stress and other symptoms are likely to be reduced. In the long run, the patient will be unlikely to easily engage in criminal activities (Fleischman et al., 2018). Lastly, vocational rehabilitation and supported employment can positively change the lives of Schizophrenia patients. Empowering these patients to a point where they have jobs to support themselves and their families reduces the chances of them engaging in crime and violence.

Conclusion In conclusion, it is concise that Schizophrenia and Crime are interconnected. The primary reason for this relationship is that Schizophrenia affects the patient’s cognition. This means that the memory, attention, and executive function of the patient are adversely affected. Due to poor reasoning and thinking, the patient is likely to engage in violence and criminal activities such as suicide. However, to eradicate this situation, Schizophrenia must be diagnosed and treated. The most effective diagnosis approaches include a physical exam, tests and screening, and psychiatric evaluation. On the other hand, psychosocial interventions such as individual and family therapy plays a central role in delinking the patient from crime.

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Evidence Supports Link Between Schizophrenia, Violent Crime

Leslie Sinclair

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Researchers in Australia recently contributed new data to the body of work on the association between schizophrenia, substance abuse, and violent criminal behavior. In an article published online June 3 in Acta Psychiatrica Scandinavica , the group—including members from the Victoria Police Crime Department, the Centre for Forensic Behavioural Science at Monash University, the Victorian Institute of Forensic Mental Health, and the Institute of Psychiatry in London—examined the relationship between committing homicide, the presence of schizophrenia, and past criminality. To do so, they evaluated contacts recorded in two statewide databases, one of which recorded public mental health service contacts and the second of which recorded contacts with the police.

James Ogloff, J.D., Ph.D.: "We have been working closely with police on the issue of policing mentally ill people. In this study, we were able to investigate the entire population of homicide offenders in Victoria, Australia, over a period of eight years."

James Ogloff, J.D., Ph.D., a professor of clinical forensic psychology at Monash University, director of psychological services for the Victorian Institute of Forensic Mental Health, and a coauthor of the report, told Psychiatric News why the research focused on one form of violent crime: "Homicide is a unique crime not only because of its severity, but also because it has among the highest of clearance rates; that is, most crimes are solved and most offenders are identified."

Estimated rates of schizophrenia disorders, substance abuse, and criminal convictions found among the 435 homicide offenders evaluated were compared with estimated rates in two composite comparison samples. Thirty-eight of the 435 offenders (8.7 percent) had been diagnosed with a schizophrenia spectrum disorder. Rates of known substance abuse between homicide offenders with and without schizophrenia and community-dwelling residents with schizophrenia did not differ significantly. However, these rates were higher than those found in the general community. A similar pattern emerged for comparisons of offending histories between these same groups. Substance misuse was determined by reviewing the two databases used for police convictions for alcohol- or drug-related charges, and for diagnoses of substance abuse or dependence disorders.

"Patients with schizophrenia are significantly more likely than those in the general community to commit homicide offenses," said Ogloff and colleagues in the report. "Known substance abuse or prior offending rates for those with schizophrenia are not more significant indicators for risk of future offending among homicide offenders than for other groups." And "most of the women and about half of the men with schizophrenia were being treated at the time of the crime," Ogloff told Psychiatric News .

The outcomes of the study are no doubt discouraging to the mental health community's efforts to convince the public that people with mental illness are not necessarily violent individuals. But the association also can't be ignored.

Recent Studies Confirm Heightened Risk

Paul Appelbaum, M.D., the Dollard Professor of Psychiatry, Medicine, and Law, director of the Division of Law, Ethics, and Psychiatry at Columbia University, and a former APA president, reviewed the study for Psychiatric News . "This paper is one of a number of recent studies that have suggested that people suffering from psychotic disorders have an increased risk of violence, especially severe violence such as homicide. Indeed, taking the research as a whole—and despite studies to the contrary—one would have to say that the weight of the evidence supports that conclusion. These researchers found that, although a history of substance abuse clearly increased the rate of homicide, it did not account for it entirely."

Appelbaum added, "There is a genuine concern that these data may heighten the stigma associated with psychotic disorders. But most people with schizophrenia are not violent, and only a very small fraction of violence in the U.S. is attributable to mental illness. Overall, however, the growing body of data suggesting a link between serious mental illness and violence should motivate us to rebuild our systems for delivering care to this population."

Police Liaison Formed

"We have been working with the police to enhance their capabilities of dealing with mentally ill offenders, and we have been working with mental health services to assist them in understanding the factors related to a risk of violence and how they might manage patients with schizophrenia at risk for violence," Ogloff told Psychiatric News . "It was very telling in our study that the vast majority of women and about half of the men with schizophrenia had been diagnosed long before they committed homicide. Several were under the care of a mental health service at the time or shortly before they committed homicide. In a few cases, there was even a clear indication that a serious act of violence was likely. Our work shows definitively that even when factors such as substance abuse are considered, the rate of schizophrenia among homicide offenders is rather dramatically higher than we see in the general community."

The results presented in this study form part of lead author Debra Bennett's doctoral studies, which were supported by Monash University.

An abstract of "Schizophrenia Disorders, Substance Abuse, and Prior Offending in a Sequential Series of 435 Homicides" is posted at < www.ncbi.nlm.nih.gov/pubmed/21644942 >.

Schizophrenia and Criminal Responsibility: A Systematic Review

PMID: 29652769
DOI: 10.1097/NMD.0000000000000805

The significant progress of psychiatry in the 20th century provided a sophisticated theoretical framework to analyze the complex relationships between crime and mental illness. Schizophrenia has been traditionally associated with severe cognitive and affective deficits that heavily influence empathy, judgment capacities, but also control of impulsiveness. Although there is an association between psychotic disorders and absence or decrease of legal responsibility, their relationship is also determined by sociodemographic, developmental, and clinical factors. These disorders are associated not only with abolished criminal responsibility but also with diminished responsibility. We conduct a systematic literature review to examine the relation between schizophrenia and criminal responsibility. We have found that this clinical entity is often associated with diminished or abolished criminal liability. We discuss these findings, focusing on the specific deficits found in patients with schizophrenia and examining how this problem affects their behavior and eventually their accountability for their crimes.

Publication types

Systematic Review
Crime / legislation & jurisprudence
Crime / psychology*
Mental Competency / legislation & jurisprudence
Mental Competency / psychology*
Schizophrenia / diagnosis
Schizophrenic Psychology*
Substance-Related Disorders / psychology

Open access
Published: 08 March 2022

Research on interpersonal violence in schizophrenia: based on different victim types

Yong He 1 ,
Meiling Yu 1 ,
Gangqin Li 1 &
Zeqing Hu 1

BMC Psychiatry volume 22 , Article number: 172 ( 2022 ) Cite this article

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Schizophrenia is one of the most common severe mental disorders associated with an increased risk of violence. The present study compares the demographical, clinical, and criminological characteristics of the patients with schizophrenia who committed different types of violence to relatives, acquaintances, or strangers.

Archives of the violent offenders with schizophrenia referred to forensic psychiatric assessments from January 2015 to December 2019 in the West China Forensic Medicine Assessment Center in China were analyzed. The demographic information, mental illness history, and criminological characteristics of the offenders were collected. The clinical symptoms, previous violent behaviors, and social deficits were also evaluated. One-way ANOVA, Kruskal–Wallis test, Chi-square test, and logistic regression analysis were enrolled to do the statistical analysis.

The study enrolled 332 cases: 165 cases (49.7%) in the acquaintance victim group (AV), 96 cases (28.9%) in the relative victim group (RV), and 71 cases (21.4%) in the stranger victim group (SV). The multinomial logistic regression analysis revealed that older patients were less likely to attack relatives (OR = 0.966, 95% CI = 0.944–0.990; p = 0.005), and strangers, (OR = 0.971, 95% CI = 0.944–0.998; p = 0.034). Patients who lived with others were more inclined to attack relatives (OR = 15.057, 95% CI = 3.508–64.628; p < 0.001). Additionally, employed patients were more likely to attack strangers (OR = 2.034, 95% CI = 1.036–3.994; p = 0.039). The regression equation did not include psychiatric symptoms. For RV and AV victims, the risk of death was higher compared to that of SV victims (OR = 13.778, p < 0.001; OR = 2.663, p = 0.014).

In the interpersonal violence cases committed by schizophrenia patients, the victim type correlates with demographic characteristics of offenders such as living situation, age, and employment status, but not with the psychiatric symptoms. The majority of victims were acquaintances and relatives, and the relative victims having more severe injuries. In order to decrease interpersonal violence, especially violent crimes, more people, especially family members and neighbors, should be educated about symptoms of schizophrenia, the ways to communicate with the patients, and the methods for crisis management.

Peer Review reports

Introduction

Schizophrenia is a severe mental disorder [ 1 ], which the public often related to violent behavior [ 2 , 3 ], and several studies have shown that schizophrenia increases the risk of violent behavior [ 4 , 5 , 6 , 7 ]. Previous studies have focused on the clinical and criminological characteristics of schizophrenia patients committing violent acts, most of whose control groups were healthy people or patients without violent behavior. Few studies have sought to compare the characteristics of schizophrenic patients who commit interpersonal violence with different victim types. The generation of interpersonal violence is an interactive process of the perpetrator and victim, relevant to the surrounding people and the environment. The course and the outcome of violent behavior from schizophrenia may vary depending on the type of victim, which may elicit different social impacts. Compared to clinical management of the mentally ill (eg. risk assessment, improved treatment), the relatively rare and unpredictable violence among psychiatric patients are more likely to raise public concerns and increase the stigma of the patients [ 8 ].

Cases of injury or murder among strangers in public places tend to raise public awareness and panic. Previous studies have also documented several forms of victimization. The investigation of homicide cases has shown that the mentally ill are less likely to attack strangers [ 9 , 10 , 11 , 12 , 13 ]. In contrast, families and friends of individuals with mental disorders face the most significant risk of harm [ 14 ]. Patients with severe mental disorders like schizophrenia commit half of the violent acts directly on family members [ 15 , 16 ]. A Japanese study showed that 34.8% of family members of schizophrenia patients had experienced physical violence from the patient [ 17 ]. According to a meta-analysis, at least 40% of relatives of mental disordered people were injured by the patients [ 18 ]. Schizophrenia has a stronger association with homicide than other diagnoses of mental disorders [ 19 , 20 ]. Among patients with mental disorders who have murdered relatives, more than 50% were schizophrenia patients [ 21 , 22 ]. Concerning the injury severity, relatives of people with mental disorders had a higher probability of suffering severe or fatal violence [ 23 , 24 ]. Psychiatric criminals have a higher propensity to commit crimes alone, in public, and against strangers than nonpsychiatric criminals [ 25 ].

The study of the risk factors related to offenders in different categories of victim is insufficient. How do demographic characteristics and clinical characteristics influence the type of victims of violence in people with schizophrenia? Moreover, what are the criminological characteristics of the offenders according to different types of victims? To answer these questions, we conducted a comparative study of forensic psychiatry assessed cases of schizophrenia suspected of violent crimes based on the categories of the victim hoping to provide a framework for identifying individuals at high risk of violent victimization and developing preventive measures.

Study subjects

We reviewed archival data of schizophrenia suspects assessed at the West China Forensic Medicine Assessment Center in Sichuan Province, China, from January 2015 to December 2019, with the inclusion criteria as following: (1) have interpersonal violence; (2) was diagnosed with schizophrenia according to the criteria of the Chinese Classification of Mental Disorders-3 rd edition (CCMD-3), and no other comorbidities; (3) Completed case data. In this study the interpersonal violence was about physical violence against others’ bodies. All the eligible cases were categorized into 3 groups according to different types of victims(relatives, acquaintances, or strangers as victims respectively).If there were multiple victims in one case, we grouped them based on the first victim. The ethics committee board of Sichuan University approved this study.

This retrospective study used a framework of forensic psychiatry sample, with the required law enforcement agencies providing the necessary information for the assessment, including demographic information, medical records, and the files of criminals. The data from their forensic psychiatric assessment and the files of criminals contain demographic, gender, ethnicity, year of birth, education level, marital status, place of residence, employment history, living situation, family history of mental illness, and drug abuse. We collected the data of criminological characteristics, the location of the interpersonal violence, the gender and relationship of the victims, the tools used, and the patients' criminal history. We applied the Brief Psychiatric Rating Scale to evaluate clinical characteristics and psychiatric symptoms, the Social Disability Screening Schedule (SDSS) to appraise the social function. We also collected the patient's past hospital visits and medication status. In the forensic psychiatric assessment center, two psychiatrists evaluated the patient's mental status according to the CCMD-3, which originated in the ninth edition of the International Classification of Diseases [ 26 , 27 ], but now corresponds to the 10th edition of the International Classification of Diseases [ 28 ].

Measurement

The brief psychiatric rating scale (bprs).

The Brief Psychiatric Rating Scale (BPRS) [ 29 ] is one of the standard instruments commonly used in daily practice to evaluate the severity of schizophrenia-related symptoms, and the 18-item scale is widely used [ 30 ]. This scale includes five subscales as follows: Affect (anxiety, guilt, depression, somatic); Positive Symptoms (thought content, conceptual disorganization, hallucinatory behavior, grandiosity); Negative Symptoms (blunted affect, emotional withdrawal, motor retardation); Resistance (hostility, uncooperativeness, suspiciousness); and Activation (excitement, tension, mannerisms-posturing) [ 31 ].

The Social Disability Screening Schedule(SDSS)

The Social Disability Screening Schedule (SDSS) used in this study was a simplified Chinese version of the World Health Organization's Disability Assessment Schedule [ 32 ], which assesses ten different aspects of social function, and each item has a score ranging from 0 to 2. The higher the score, the worse the social function outcome. Twelve areas epidemiological survey of mental disorders in China stipulated a total score of ≥ 2 points, which indicates a functional social deficit [ 33 ].

Statistical analysis

All analyses were performed using IBM SPSS Statistics (version 20.0). The significance level was 0.05 (2-sided). Three independent groups were compared using a one-way analysis of variance (ANOVA) or the Kruskal–Wallis H test. The Chi-squared test was used to compare the categorical variables across the three groups. Bonferroni’s correction for multiple comparisons was used for pairwise comparisons between groups. Multinomial logistic regression was used to analyze the risk factors for offenders targeting different type of victims.

A total of 332 cases were included in the current study, while 165 cases (49.7%) in the Acquaintances Victim group (AV), 96 cases (28.9%) in the Relatives Victim group (RV), and 71 cases (21.4%) in the Stranger Victim group (SV). The average age of the offenders was 40.16 ± 12.04 years old, 97.0% were Chinese Han population, and 81.0% were men. There were 79.2% of the offenders had a low level of education (≤ 9 years), most of them lived in rural areas (73.2%), and 23.5% of them never had a job before. There were 79.2% of the patients were unemployed at the time of the violence. Regarding marriage, only 36.4% were married, while the rest were unmarried, divorced, or widowed. In terms of the living situation, 79.2% lived with others and 20.8% lived alone. A total of 73.8% had sought treatment in a psychiatric facility before the violence occurred, and 55.1% were hospitalized. The majority of patients (67.4%) had the disease for more than five years. Nearly four-fifths of the patients did not take medicine at the time of committing the violence. A family history of mental illness is present in 8.7% of cases. The percentage of patients with a criminal record was 9.3%. Regarding substance use, 12.3% of offenders drank alcohol before committing the interpersonal violence, and none were drug users (Table 1 ).

For the types of interpersonal violence, 217 cases (65.4%) were physical assault, and 115 cases (34,6%) were murder. In terms of the location of the interpersonal violence, public places accounted for the highest proportion at 52.1%, followed by co-residence 23.2%, and victim residence (16.9%); 83.7% of suspected offenders used tools, of which 48.2% brought tools to the criminal scene, and 51.8% used tools on-site. There were 84.6% offenders had repeated attack behavior. In 41.3% of the cases, the victims contain at least one woman, and in 35.8% of the cases, the victims encountered death problems (Table 1 ).

Comparison of characteristics among groups

Demographic characteristics

Gender, ethnicity, education level, and employment history did not differ among the groups ( p > 0.05). In addition, differences among the three groups were found based on demographic factors such as age, living situation, employment status, place of residence, and marital status. The age of the AV (42.98 ± 12.75 years old) was significantly higher than that of the RV (37.07 ± 11.36 years old) and the SV (37.79 ± 9.56 years old) statistically ( p < 0.001). By living situation, more patients lived with others in the RV (97.9%) group than the AV (72.1%) and SV (70.4%) ( p < 0.001). Regarding the employment status, more patients in the SV group were in employment compared to those in the AV (17.0%) and RV (17.7%) ( p = 0.009). A marginal significant difference was found in place of residence categories ( p = 0.056) and marital status ( p = 0.050), that a higher percentage of schizophrenia offenders attacking acquaintances living in the rural area (78.8%) compared to those in the RV (69.8%) and SV (64.8%). The proportion of married patients in the SV (28.2%) was lower than that of the AV (34.5%) and RV (45.8%) ( p = 0.050), (Table 2 ).

Clinical characteristics

In concern of the clinical characteristics, there were no statistically significant differences in terms of the history of psychiatric treatment, hospitalization, illness duration, treatment, and alcohol use when committing the index interpersonal violence, as well as family history of mental disorders ( p > 0.05)(Table 2 ).

Regarding the social function, the median score of SDSS for offenders in RV was 8.00, in AV was 8.00, and in SV was 7.00, and the score distributions did not differ significantly among the three groups (H = 4.075, p = 0.130) (Table 3 ).

The BPRS indicated no significant differences in the affect and activation scores among groups ( p > 0.05), however, it showed statistically significant differences in positive symptoms (H = 9.604, p = 0.008), negative symptoms (H = 13.026, p = 0.001), resistance (H = 12.571, p = 0.002), and the total score (F = 7.386, p = 0.001) among the three groups. Pairwise comparison after Bonferroni post hoc test found that the median scores of positive symptoms, negative symptoms, and resistance were significantly lower in the SV group than the other two groups ( p < 0.05); there was no statistically significant difference in psychiatric symptom scores between the AV group and the RV group ( p > 0.05) (Table 3 ).

Criminological characteristics

There was a higher proportion (15.5%) of offenders in the SV who had previous criminal history than that in the RV (5.2%) and AV (9.1%) ( p = 0.077). And there was a significant difference regarding the interpersonal violence location and types among the three groups ( p < 0.001). Murders were more likely to occur among relatives (65.6%), while physical assault in acquaintances (73.9%) and strangers (87.3%). Violence targeting relatives occurred more often in the co-residence of the perpetrator and the victim (72.9%), while attacking acquaintances occurred more often in public places (57.0%) and the victims’ residence (29.1%). Cases in which the victims were strangers occurred more often in public places (88.7%). Regarding the gender of victims, 41.3% of cases involved female victims, and the difference among the RV (59.4%), the AV (37.0%), and SV (26.8%) was statistically significant ( p < 0.001). In terms of the severity, victims deceased in 35.8% of cases. The RV had the highest death rate of 66.7%, followed by the AV (27.9%), and the lowest was the SV (12.7%) ( p < 0.001). Pairwise comparison after Bonferroni post hoc test also showed that the differences between the three groups were statistically significant. There were 83.7% of the offenders used tools, among which the RV used tools on-site in the highest proportion, accounting for 74.0%, while the other two groups’ patients brought their tools were 49.1% and 52.1%, respectively, accounted for the highest percentage (Table 2 ). About specific victim relationships, in the RV, the parent (32.3%) had the highest proportion, followed by the spouse (24.0%); in the AV, the neighbor (73.3%) had the highest percentage. For the occurrence of death, the death risk of the RV was 13.78 times(95% CI 6.081, 31.215, p < 0.001) higher than that in the SV; when it comes to the AV, the risk of death was 2.66 times (95%CI 1.224, 5.795, p = 0.014) higher than that of the SV.

Multinomial logistic regression analysis

To assess the risk factors of different victim types, we used multinomial logistic regression to analyze the demographic characteristics and clinical characteristics analysis with p < 0.05. The multinomial logistic regression analysis taking the AV group as a reference revealed that older patients had a lower possibility of attacking relatives, OR = 0.966, 95% CI = 0.9440.990, p = 0.005, and strangers, OR = 0.971, 95% CI = 0.9440.998, p = 0.034. This analysis also revealed that patients who lived with others were more likely to attack relatives, OR = 15.057, 95% CI = 3.508 - 64.628, p < 0.001, Furthermore, patients who were employed were more likely to attack strangers OR = 2.034, 95% CI = 1.036- 3.994, p = 0.039. The regression equation did not include psychiatric symptoms (Table 4 ).

In our study, the highest percentage of victims was acquaintances (49.7%), followed by relatives (28.9%) and strangers (21.4%). The proportion of relatives was lower than that reported in two previous studies, whereas the rate of relatives was 69.4% and 43.1%, respectively [ 15 , 16 ], while higher than that of a study in Sweden with 13% [ 24 ], and comparable to Morgan with 33.3% [ 25 ]. Different characteristic of offenders may result in the difference of victim targets. Some relatives of the schizophrenic patients may consider violence as an inevitable consequence of the disorder and tolerate the patient's violent behavior [ 34 ]. Generally, the victims would not report to the police unless being severely injured. However, the patient would usually be punished by law when committing violent acts against people outside the family. This may be one of the reasons why the data based on police records differ from the results of community surveys. In a Swedish study [ 24 ], only 13% of victims were relatives, while strangers made up 55.8%. In our study, strangers accounted for only 21.4%. This difference may also be from the study sample, in our study, we only focus on the original victim that was the first one being violently attacked. Police, security officers, and other people who were victimized in order to prevent the consequences of serious injuries were excluded, however, these kinds of victims were categorized as strangers in the aforementioned Swedish study [ 24 ].

In this study, the BPRS scores on positive symptoms, negative symptoms, and resistance symptoms of the offenders attacking strangers were lower than those attacking relatives and acquaintance. However, the multinomial regression analysis did not find significant contribution of these symptoms to the different types of victims, which suggesting that mental symptoms may not be the primary determinant of the type of victim.

A survey on schizophrenia patients who harm relatives and strangers found that insults, threats, and forced hospitalization were the primary inducement for the violence [ 35 ]. Patients who kill strangers are more likely to be homeless, exhibit anti-social behavior, and have fewer negative symptoms than those who kill family members [ 12 ].

Psychotic symptoms and violence have been associated for a long time, but the specific mechanism remains a mystery. Researchers have found that persecuted delusions can contribute to violent behavior in patients with schizophrenia [ 6 ], and delusions or hallucinations are related to violent behavior [ 36 , 37 ]. However, studies have shown that delusions do not increase the patient’s overall violence risk, although they may impact individual patients’ violent behavior [ 38 ]. Delusional behavior does not typically lead to violent behavior [ 39 ], and rarely does the patient kills the victim by obeying the commanded auditory hallucination [ 35 , 40 ]. The occurrence of violent behavior may be a maladaptive resolution of conflict by the patient [ 41 ] or enhanced response to the stress in the stimulus situation [ 42 ]. The chances of people exhibiting aggressive behavior are higher when they feel scared [ 43 ].

Patients with schizophrenia frequently have concomitant cognitive impairment [ 1 , 44 ]. Studies have shown that executive dysfunction is related to violent behavior [ 45 , 46 ], because of the impairment of ability to adapt to the environment. It is sometimes complicated for individuals to adapt their behavior to environmental changes and to have inadequate inhibition, resulting in maladaptive challenges in social settings and more violent responses [ 46 ]. Unable to deal with conflicts reasonably, the presence of psychotic symptoms such as delusions and hallucinations may simply increase the probability of a patient experiencing conflict, however, whether violent behavior will eventually occur, is associated with the patient's executive function and other cognitive abilities to assess and implement a specific conflict processing strategy.

Taken together, symptoms, perpetrator-victim relationships, and circumstances may interact in complex ways to lead to violence. According to the Situation Action Theory (SAT) [ 47 , 48 ], the act of crime results from a perception-choice process of persons’ crime propensity and criminogenic exposure, and SAT maintains that acts of crime are best explained as moral actions. And a person’s crime propensity was a consequence of their morality and ability to exercise self-control. The influence of a setting’s moral context on action is always a question of its perceived moral context. A person’s criminogenic exposure may be seen as his or her encounters with settings in which the (perceived) moral norms and their (perceived) levels of enforcement (or lack of enforcement) encourage reaches of rules of conduct (stated in law) in response to particular opportunities or frictions in their daily life [ 48 ]. Suffering from schizophrenia may influence the patients’ morality and ability to exercise self-control and accurate perception of moral norms and enforcement in settings.

The multinomial regression analysis showed that employed and younger patients were more likely to attack strangers, and the younger patients living with others were more likely to attack relatives. The age, living situation, and employment may affect the living circumstances and the opportunity to connect with others. The stranger group of employed offenders can participate in more social life activities, and these activities reach out to more people than the other two groups, so it is more likely to contact strangers. Furthermore, they were less often co-live with others, lacking reasonable and adequate care and supervision. In the case of a patient confined at home, we assume a low risk of him or her harm a stranger.

The RV was more likely to live with others, and about 72.9% of the RV cases occurred at their co-residence, which suggests that most of the patients who attacked relatives were at home and had a small personal social circle, and the reason may be that they can only contact the relative who is caregivers at the most of the time.

The RV has a high proportion of cases involving female victims, which is consistent with previous studies showing that women account for most family victims [ 14 , 15 , 24 ] because caregivers of the patients were mainly spouses or mothers. In a survey of schizophrenia patients with parricide, 98.1% lived with their parents [ 35 ]. Patients with schizophrenia may have some behavioral disorders due to the impact of the disease. Parents and other co-residents would ask them to do things such as not hanging out at night, not smoking at night, cleaning their room, regularly eating, taking medication, and saving [ 35 ]. The patient may perceive these restricted behaviors as parental intimidation and hostility toward them [ 49 ]. However, as the main caregiver, mothers play a significant role in compulsory drug feeding, forced hospitalization, and providing discipline. As a result, conflicts between caregivers and patients occurred, and patients would attack co-living people. Patients often inflict violence on their victims before their homicide occurred, with 40.7% of patients violently abusing their victims before the homicide occurred [ 35 ].Regarding the severity of victimization, the incidence of death in the relative group exceeded that of the other two groups significantly. Previous studies have also shown that patients with mental disorders inflict more severe injuries on their relatives [ 24 ]. A possible explanation would be the location of the incident, considering that most cases occurred in the co-residence. It was easier for the offender to obtain tools such as knives and sticks because the offender was familiar with the area, and the severity of the attack was more significant than if the offender had no tools. Outsiders cannot prevent violence and treat victims because of the relatively secretive environment of the incident, which increases the risk of death for the victim. Furthermore, since the study sample was drawn from physical assault and murder cases of schizophrenic patients identified by public security organs, some less severe injuries in the relative victims possibly were not included in the study sample.

People’s movement patterns are determined by their individual routine activities and that people offend is related to their activity fields [ 48 ]. Frictions with their caregivers in daily life may also influence the patient’s criminogenic exposure. In China, family members are primarily responsible for supervising patients with mental disorders [ 50 , 51 ]. However, the majority of family members lack the knowledge and ability to coping violent crisis of mentally ill [ 51 ]. Many patients have recurrent symptoms due to inadequate or incorrect treatment [ 52 , 53 ]. As a result of residual symptoms [ 54 ], impaired cognitive and emotional function [ 44 , 55 ], or stigma [ 56 , 57 ], these patients repeatedly committed violent crimes. In this condition, the basic knowledge of mental disorders and violence prevention skills for family caregivers should be strengthened, which is crucial to disease rehabilitation and violence prevention. In the meanwhile, the community and government should make effort to construct a long-term sensible and reasonable management system for patients with mental disorders to improve their rehabilitation.

Limitations

There are some limitations need to be addressed in the current study. First, we only included cases from one forensic medicine assessment center in Sichuan province. Although this forensic center is responsible for most of the forensic psychiatric assessments for offenders with mental disorder in Sichuan Province (home to over 80 million people) [ 58 ], the findings may not be generalized to the entire country or other regions. However, the analytic methodology demonstrated in this study could be adopted for analysis in other regions. Second, due to the limitation of retrospective study, some information of the offenders such as the education level data were missing.

In the interpersonal violence cases committed by schizophrenia patients, the victim type correlates with demographic characteristics of offenders such as living situation, age, and employment status, but not with the psychiatric symptoms. Acquaintances and relatives are more likely to be injured by schizophrenic patients, Co-residents, caregivers and relatives were more vulnerable to suffer severe violence, especially the females.

It is essential to establish a guardianship system for patients with schizophrenia to improve caregiver awareness of the disease and risk management methods.

Availability of data and materials

The data that support the findings of this study will be available from the corresponding author on reasonable request. The data are not publicly available due to the sensitivity of the subjects.

Abbreviations

The third edition of the Chinese Classification of Mental Disorder

Relatives victim group

Acquaintances victim group

Stranger victim group

The Brief Psychiatric Rating Scale

The Social Disability Screening Schedule

Situation Action Theory

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Acknowledgements

We are much thankful to those who supported this project.

This work was supported by China Postdoctoral Science Foundation [grant number 2018M643488]; the National Natural Science Foundation of China [grant number 81901928].

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ZQH, GQL and YH conceived and designed the study, ZQH and GQL provided oversight and direction. YH, YL, and MLY contributed to data extracting. YH and YG contributed to data analysis and interpretation. YH drafted the manuscript. YH, ZQH, YG, MLY, and YL contributed to the revision of the manuscript. All authors have approved the final manuscript.

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He, Y., Gu, Y., Yu, M. et al. Research on interpersonal violence in schizophrenia: based on different victim types. BMC Psychiatry 22 , 172 (2022). https://doi.org/10.1186/s12888-022-03820-7

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The comorbid relationship between schizophrenia and crime may prove difficult to accept by some researchers, practitioners, and the public alike. However, over the last 50 years, accumulating evidence from several follow-up studies and retrospective studies of birth cohorts, patients, and incarcerated populations globally, have established the schizophrenia and crime link. This chapter reviews the growing empirical evidence to date on the risk-factors and cures associated with schizophrenia, crime, and for both of these conditions. By understanding the etiology of this comorbid relationship, we can reduce the stigma that is associated with these disabling conditions and importantly, begin to direct more resources into developing preventive interventions for individuals at-risk for developing these disabling conditions.

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Wong, K.KY. (2020). Schizophrenia and Crime. In: Zeigler-Hill, V., Shackelford, T.K. (eds) Encyclopedia of Personality and Individual Differences. Springer, Cham. https://doi.org/10.1007/978-3-319-24612-3_2315

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Fazel S , Långström N , Hjern A , Grann M , Lichtenstein P. Schizophrenia, Substance Abuse, and Violent Crime. JAMA. 2009;301(19):2016–2023. doi:10.1001/jama.2009.675

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Schizophrenia, Substance Abuse, and Violent Crime

Author Affiliations: Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, England (Dr Fazel); Centre for Violence Prevention (Drs Fazel, Långström, and Grann) and Department of Medical Epidemiology and Biostatistics (Drs Långström and Lichtenstein), Karolinska Institutet, Centre for Epidemiology, National Board of Health and Welfare (Dr Hjern), and Department of Psychology, Stockholm University (Dr Grann), Stockholm, Sweden; and Department of Children's and Women's Health, University of Uppsala, Uppsala, Sweden (Dr Hjern).

Context Persons with schizophrenia are thought to be at increased risk of committing violent crime 4 to 6 times the level of general population individuals without this disorder. However, risk estimates vary substantially across studies, and considerable uncertainty exists as to what mediates this elevated risk. Despite this uncertainty, current guidelines recommend that violence risk assessment should be conducted for all patients with schizophrenia.

Objective To determine the risk of violent crime among patients diagnosed as having schizophrenia and the role of substance abuse in mediating this risk.

Design, Setting, and Participants Longitudinal designs were used to link data from nationwide Swedish registers of hospital admissions and criminal convictions in 1973-2006. Risk of violent crime in patients after diagnosis of schizophrenia (n = 8003) was compared with that among general population controls (n = 80 025). Potential confounders (age, sex, income, and marital and immigrant status) and mediators (substance abuse comorbidity) were measured at baseline. To study familial confounding, we also investigated risk of violence among unaffected siblings (n = 8123) of patients with schizophrenia. Information on treatment was not available.

Main Outcome Measure Violent crime (any criminal conviction for homicide, assault, robbery, arson, any sexual offense, illegal threats, or intimidation).

Results In patients with schizophrenia, 1054 (13.2%) had at least 1 violent offense compared with 4276 (5.3%) of general population controls (adjusted odds ratio [OR], 2.0; 95% confidence interval [CI], 1.8-2.2). The risk was mostly confined to patients with substance abuse comorbidity (of whom 27.6% committed an offense), yielding an increased risk of violent crime among such patients (adjusted OR, 4.4; 95% CI, 3.9-5.0), whereas the risk increase was small in schizophrenia patients without substance abuse comorbidity (8.5% of whom had at least 1 violent offense; adjusted OR, 1.2; 95% CI, 1.1-1.4; P <.001 for interaction). The risk increase among those with substance abuse comorbidity was significantly less pronounced when unaffected siblings were used as controls (28.3% of those with schizophrenia had a violent offense compared with 17.9% of their unaffected siblings; adjusted OR, 1.8; 95% CI, 1.4-2.4; P <.001 for interaction), suggesting significant familial (genetic or early environmental) confounding of the association between schizophrenia and violence.

Conclusions Schizophrenia was associated with an increased risk of violent crime in this longitudinal study. This association was attenuated by adjustment for substance abuse, suggesting a mediating effect. The role of risk assessment, management, and treatment in individuals with comorbidity needs further examination.

More than 20 epidemiological studies have reported on the association between major mental disorder and violence, including more than 10 that specifically have examined the relationship with schizophrenia. 1 These reports typically find that schizophrenia is related to a 4- to 6-fold increased risk of violent behavior, which has led to the view that schizophrenia and other major mental disorders are preventable causes of violence and violent crime. Indeed, expert opinion has deemed that the evidence is sufficiently robust that new research should move beyond epidemiology and focus on treatment. 2 , 3

However, uncertainties remain regarding the reported link. First, there are wide variations in risk estimates. These range from 7-fold increases in violent offenses in schizophrenia compared with general population controls 4 , 5 to no association in 1 prospective investigation. 6 Second, there is considerable uncertainty whether schizophrenia without substance abuse comorbidity is actually associated with violence. Large prospective and case-control studies have found no or only a weak association, 5 , 6 while other investigations from Finland, Denmark, and the United States report 3- to 4-fold risk increases. 7 - 9 Third, the possible contribution of genetic and early environmental factors in mediating the link between schizophrenia and violence has not been reliably studied. 10

Conceptual models of violence in schizophrenia postulate that patients with schizophrenia are violent as a consequence of the psychopathologic symptoms of the disorder itself (eg, delusions, hallucinations 11 ) or secondary to comorbid substance use (an established risk factor for violence 12 ). An alternative model is that schizophrenia and violent behavior co-occur because of familial factors (genetic or early environmental) that are related to both (eg, personality traits such as irritability, poor anger management, or inadequate coping with stress).

If, as we hypothesize, the association of schizophrenia and violence disappears when substance abuse is accounted for and appropriate adjustments are made for confounding, this would suggest that assessment and treatment for substance abuse comorbidity should be prioritized in individuals deemed at risk. It would also explain why attempts to find psychotic symptoms associated with violence have produced contradictory results. 11 , 13 , 14 Therefore, by using longitudinal designs, we examined the relationship of schizophrenia with violent crime in Sweden from 1973 until 2006.

We linked several nationwide population-based registries in Sweden: the Hospital Discharge Registry (HDR; held at the National Board of Health and Welfare), the Crime Register (National Council for Crime Prevention), the National Censuses from 1970 and 1990 (Statistics Sweden), and the Multi-Generation Register (MGR; Statistics Sweden). We also merged data with the causes of death register and the total population register (for emigration data) to provide information on loss to follow-up. In Sweden, all residents including immigrants have a unique 10-digit personal identification number that is used in all national registers, thus making the linking of data in these registers possible.

Using the HDR, which includes all individuals admitted to any psychiatric or general medical hospital for assessment and/or treatment (including forensic psychiatric hospitals and the few private providers of inpatient health care), we identified as cases individuals who fulfilled 2 criteria. First, they had been discharged from hospitals beginning in January 1, 1973, and had discharge diagnoses of schizophrenia on at least 2 separate inpatient hospitalizations according to the International Classification of Diseases, Eighth Revision ( ICD-8 ) (1973-1986; diagnostic code 295), International Classification of Diseases, Ninth Revision ( ICD-9 ) (1987-1996; code 295), or International Classification of Diseases, 10th Revision (ICD-10) (from 1997 onward; code F20), irrespective of any comorbidity. Second, they were born between 1958 and 1989, so that they were aged at least 15 years (the age of criminal responsibility) at the start of the study in 1973. We decided that schizophrenia had to be diagnosed on 2 separate occasions to increase diagnostic precision by minimizing false-positive diagnoses 15 ; hence, those with only 1 diagnosis were excluded. More than 90% of individuals with schizophrenia were admitted during a 10-year period in Sweden. 16 Beginning in 1973, the hospital discharge register had national coverage. No information was available on patients treated solely in outpatient facilities.

For all individuals, data were also extracted on admissions from 1973 onward with principal or comorbid diagnoses of alcohol abuse or dependence ( ICD-8 : code 303; ICD-9 : codes 303, 305.1; ICD-10 : code F10, except x.5) and drug abuse or dependence ( ICD-8 : 304; ICD-9 : 304, 305.9; ICD-10 : F11-F19, except x.5). This information was used as a marker for comorbid alcohol and/or drug abuse disorders.

Swedish HDR schizophrenia diagnoses show good concordance rates (κ>0.70) with diagnoses based on Opcrit record review (a 90-item checklist of signs and symptoms generating Diagnostic and Statistical Manual of Mental Disorders ( DSM ) and ICD diagnoses developed for use in both European and US samples 17 ) and interview (generating a DSM [Fourth Edition] [ DSM-IV ] diagnosis of schizophrenia). 18 In another study, 86% of HDR schizophrenia diagnoses corresponded with DSM-IV diagnoses of schizophrenia made from file-based reviews by psychiatrists. 19 However, the specificity is fair at best. 18 Hence, some individuals with schizophrenia are diagnosed as having other mental disorders during any particular inpatient episode, which forms the basis of our decision to use 2 diagnoses to define cases. Only about 1% of hospital admissions have missing personal identification numbers. 20 Consequently, the register has been widely used in psychiatric epidemiological investigations. 20 , 21

In relation to substance abuse diagnoses, prior validity studies have found fair agreement between substance abuse diagnoses in the HDR and more comprehensive inpatient assessments. 22 We conducted a new and substantially larger analysis, which focused on individuals with schizophrenia. We extracted all individuals with a diagnosis of schizophrenia in the HDR and who had an inpatient forensic psychiatric assessment using a national register of all such evaluations from 1988-2000 (n = 1638). The latter acted as our gold standard because these cases involved comprehensive multidisciplinary evaluations over 4 weeks in inpatient settings, yielding standardized consensus diagnoses. 23 , 24 The assessment included detailed review of medical, educational, and social services records; psychological testing; repeated mental state examinations; and interviews with family members and other informants. We found a κ of 0.37 (SE, 0.23; P < .001, corresponding to 68% agreement) for HDR diagnoses of comorbid substance abuse in individuals with schizophrenia, indicating fair to moderate agreement. 25

We investigated 2 overlapping samples of individuals with schizophrenia. The first was a national sample of those with 2 or more hospital diagnoses of schizophrenia (n = 8003). The second, which was a subgroup of the first sample, was all individuals with 2 or more hospital diagnoses of schizophrenia who had unaffected full siblings (n = 4674). We identified comparison groups who had never been hospitalized for schizophrenia during the study period. The first was a random selection of 10 general population individuals matched by birth year and sex for each individual with schizophrenia (n = 80 025 general population controls and n = 8003 patients with schizophrenia). The second comparison was unaffected full siblings compared with those with schizophrenia (n = 7780 full sibling controls and n = 4674 individuals with schizophrenia), unmatched by age or sex and identified using the MGR. 26 The MGR connects each person born in Sweden in 1933 or later and ever registered as living in Sweden after 1960 to their parents. 27 For immigrants, similar information exists for those who became citizens of Sweden before age 18 years together with one or both parents.

Data on all convictions for violent crime beginning in January 1, 1973, were retrieved for all individuals aged 15 years or older (the age of criminal responsibility in Sweden). In keeping with other work, violent crime was defined as homicide, assault, robbery, arson, any sexual offense (rape, sexual coercion, child molestation, indecent exposure, or sexual harassment), illegal threats, or intimidation 20 (hence, burglary and other property offenses, traffic offenses, and drug offenses were excluded). Attempted and aggravated forms of included offenses, where applicable according to the Swedish criminal code, were also included. We followed these 2 cohorts until December 31, 2004, and a second set of cohorts until December 31, 2006.

Conviction data were used because the criminal code in Sweden determines that individuals are convicted as guilty regardless of mental illness. Therefore, it includes also those who are found not guilty by reason of insanity (who would be acquitted in other jurisdictions), persons who received custodial or noncustodial sentences, and individuals transferred to forensic hospitals (eg, individuals who were psychiatrically assessed and found to have had psychosis at the time of the offense). Furthermore, conviction data included cases in which the prosecutor decided to caution or fine. In addition, because plea bargaining is not permitted in Sweden, conviction data accurately reflect the extent of officially resolved criminality. The crime register has excellent coverage; only 0.05% of crimes had incomplete personal identification numbers in 1988-2000. 20

Data on civil status and income were gathered from the 1970 and 1990 national censuses. For income, if there were no 1990 census data, we used 1970 data and converted these to the 1990 monetary value. This was then divided into tertiles (low, medium, and high) for the purposes of further analysis. When data on individual income were missing, we used the household income (also divided into tertiles) of the family of origin for those aged 15 years or younger at the time of the 1990 or 1970 censuses. Single marital status was defined as being unmarried, divorced, or widowed. Immigrant status was defined as being born outside of Sweden or having at least 1 parent born outside of Sweden. No data on homelessness were available. In the main analyses, missing data were not replaced by imputation or other methods.

We estimated the association between schizophrenia and violent offenses with conditional logistic regression, as per related work using matched and/or sibling controls, 15 , 28 using the clogit command in Stata software, version 10 (Stata Corp, College Station, Texas). The clogit command fits conditional (fixed-effects) logistic regression models to matched case-control groups. Only offenses occurring after the second inpatient diagnosis of schizophrenia were included in the analyses. We analyzed data per convicted individual, regardless of the number of individual counts of crime per conviction.

Ten controls from the general population were selected for each case. In the sibling control study, all unaffected siblings were compared with each individual with schizophrenia. Age and sex were matched or adjusted for in all analyses. In the general population study, controls were matched by birth year and sex. In the sibling control investigation, age was adjusted for in analyses involving full-sibling comparisons by calculating the age difference (in years) between proband and sibling, and sex was also adjusted for.

We tested possible confounders (income, marital status, and immigrant status) by examining whether they were each independently associated with a diagnosis of schizophrenia and violent crime using χ 2 tests, and we included them as covariates in adjusted models if they were associated with violence in both univariate analyses at the .05 level of significance. 29 Immigrant status was a confounder only for risk of violent crime in those with schizophrenia compared with general population controls. Collinearity between confounders was tested using the collin command in Stata, and we found no evidence of significant collinearity—the mean variance inflation factor was 1.0 (where a value of 10 would indicate significant collinearity). 30

Because substance abuse could be on the causal pathway between schizophrenia and violent crime, it has been argued that it is not appropriate to include it as a confounder in regression modeling. 31 Another argument for not including substance abuse as a confounder is whether effect modification occurred (whether the risk increase for substance abuse was of a similar degree in patients as it was in controls).

We used the likelihood ratio test (with a P < .05 indicating a significant interaction) and we also fitted an interaction term into the model to test this. In building the model, all significant confounders were included simultaneously in addition to the outcome of interest (violent crime). To test the validity of the model, we performed the Shapiro-Francia normality test on the residuals and found no evidence of nonnormality ( P = .50).

Power calculations (with an α level of .10 and power of 90%) suggested that 750 cases and 7500 controls were needed to determine a 2-fold difference in rates of violent offenses and 2500 cases and 25 000 controls to determine a 1.5-fold difference.

To corroborate our results, we performed a series of sensitivity analyses. First, to test whether there was any secular trend, we selected all individuals with 2 or more diagnoses of schizophrenia born between January 1, 1972, and December 31, 1981 (n = 1348; ie, a subgroup of the first sample). We again randomly selected 10 general population controls matched by birth year and sex for each individual in this sample (n = 13 480) and were able to follow up this cohort through December 31, 2006. Because there were only 633 cases with unaffected siblings in this cohort (and 829 unaffected siblings), we did not perform stratification on substance abuse for sibling comparisons. Second, we examined risk of severe violent offense in individuals with schizophrenia. For this analysis, we defined severe violence as homicide, serious (or aggravated) assault, rape, sexual coercion and child molestation, or robbery. Third, to investigate possible differential loss to follow-up for cases and controls, we examined risk of violent crime after excluding individuals who emigrated or died during follow-up. Fourth, we investigated the effect of the timing of substance abuse comorbidity on risk of violence in schizophrenia. Hence, we compared the risk of violent crime in those with a substance abuse diagnosis before or at the same time as their second schizophrenia diagnosis with general population controls, and the risk in those who had a substance abuse diagnosis after their second schizophrenia diagnosis in relation to general population controls. Fifth, because our analysis excluded individuals with missing data, we recalculated the risk estimates with the addition of these individuals. For this subanalysis, an extra category was assigned to missing income and marital status information so that the model included all cases and controls. Finally, we investigated whether diagnosis of schizophrenia based on 1 hospital diagnosis provided different risk estimates. For this analysis, we used the cohort described above who were born between 1972 and 1981 (n = 2107 with schizophrenia and 21 070 randomly selected general population controls). This represented an additional 56% of individuals with schizophrenia compared with case ascertainment based on 2 hospital diagnoses.

The Regional Ethics Committee at the Karolinska Institutet, Stockholm, approved the study. Data were merged and anonymized by an independent government agency (Statistics Sweden), and the code linking the personal identification numbers to the new case numbers was destroyed immediately after merging. Therefore, informed consent was not required.

Basic sociodemographic information and substance abuse comorbidity among individuals with schizophrenia and controls in the 2 samples are presented in Table 1 . The prevalence of convictions for violent crime in individuals with schizophrenia was approximately 12% to 13% ( Table 2 ), with median times from discharge to offense of 1132 days for patients in the general population study and 1214 days for patients in the sibling comparison sample. Overall, 6583 patients and general population controls (7.5%) and 571 patients and their sibling controls (4.5%) died or emigrated during follow-up. In the general population study, there were 141 violent offenders (12.5%) among cases who died or emigrated during follow-up compared with 913 violent offenders (13.3%) among cases who did not die or emigrate during follow-up (χ21 = 0.50; P = .48). Approximately 5% to 8% of control individuals were convicted of violent crimes ( P < .001 for all comparisons; Table 2 ). There was an increased risk of violent crime among individuals diagnosed as having schizophrenia: adjusted odds ratios (ORs) were 2.0 (95% confidence interval [CI], 1.8-2.2) when general population controls were used and 1.6 (95% CI, 1.3-1.8) when unaffected siblings were controls ( Table 2 ).

We found evidence of effect modification between substance abuse comorbidity and schizophrenia on the risk of violent criminal convictions in the general population sample (likelihood ratio: χ21 = 52.7; P < .001; interaction term: z = 10.1; P < .001). Therefore, we stratified the analyses of the association between schizophrenia and violent crime by substance abuse comorbidity.

The rate of violent crime in individuals diagnosed as having schizophrenia and substance abuse comorbidity (27.6%) was significantly higher than in those without comorbidity (8.5%), which resulted in adjusted ORs of 4.4 (95% CI, 3.9-5.0) for violent crime in schizophrenia with substance abuse and 1.2 (95% CI, 1.1-1.4) in schizophrenia without substance abuse ( P < .001 for interaction) ( Table 3 ). For sibling comparisons, the rate of violent offense in individuals with schizophrenia and comorbidity was 28.3% compared with 17.9% among unaffected siblings and was 7.2% in schizophrenia without comorbidity compared with 5.4% in unaffected siblings. This corresponded to adjusted ORs for violent crime of 1.8 (95% CI, 1.4-2.4) in patients with substance abuse and 1.3 (95% CI, 1.0-1.4) in patients without substance abuse (likelihood ratio: χ21 = 24.4; P < .001; interaction term: z = 4.9; P < .001). The rate of substance abuse among unaffected siblings of cases with substance abuse comorbidity was 9.7% compared with 3.3% in siblings of cases without substance abuse comorbidity.

Risk of violent outcomes in schizophrenia was significantly increased compared with unaffected controls when a more severe definition of violent crime was used, when individuals who died or emigrated during follow-up were excluded, and when case ascertainment was based on only 1 hospital diagnosis of schizophrenia ( Table 4 ). When we extended the follow-up period through 2006, risk estimates were significantly increased compared with general population controls and were nonsignificantly increased compared with unaffected siblings ( Table 4 ). In addition, when follow-up was extended, we found a significant increase in the risk estimate for violent crime in cases with substance abuse comorbidity compared with general population controls. In patients with schizophrenia, 102 of 1012 (10.1%) without substance abuse comorbidity had at least 1 violent offense (adjusted OR, 1.8; 95% CI, 1.4-2.3) compared with 97 of 336 (28.9%) cases with substance abuse comorbidity (adjusted OR, 5.8; 95% CI, 4.4-7.6). When individuals with missing data on income and marital status were included into the model, risk estimates were also significantly increased compared with unaffected controls. For the general population comparison, the adjusted OR was 2.1 (95% CI, 1.9-2.1) and for the sibling control comparison, the adjusted OR was 1.5 (95% CI, 1.3-1.8).

The effect of the timing of substance abuse in schizophrenia was possible to analyze in the general population study, but not when using sibling control data for reasons of statistical power. Patients with schizophrenia diagnosed as having substance abuse on the same day or before their inpatient episode for schizophrenia had a lower rate of violent crime (15.6% or 112/716 [15.6%]) compared with those diagnosed as having substance abuse after their schizophrenia diagnosis (429/1243 [34.5%]). The corresponding adjusted OR for risk of violent offense compared with general population controls was 1.9 (95% CI, 1.5-2.5) in those with substance abuse before a diagnosis of schizophrenia. The adjusted OR was 6.4 (95% CI, 5.4-7.5) in those with substance abuse comorbidity after their diagnosis of schizophrenia. Adjustments were made for age, sex, marital status, immigrant status, and income.

We used complementary longitudinal study designs to investigate the risk of violence in individuals with schizophrenia compared with unaffected controls with varying degrees of relatedness to the index individual with schizophrenia. Apart from the large number of individuals diagnosed as having schizophrenia included in this report (n = 8003), more than all previous longitudinal studies combined, this study advances knowledge in 2 other ways. First, to reduce misclassification by incorrect inclusion of nonpsychotic diagnostic groups such as personality disorder and substance abuse (which are themselves associated with violence 32 , 33 ), we only included as cases those with schizophrenia diagnosed on at least 2 separate occasions. Second, we adjusted for confounding more precisely than prior work in a number of ways. We used unaffected siblings as controls, for the first time to our knowledge in this field. This design provides a powerful way to adjust for residual familial confounding. In addition, we accounted for cohort effects by adjusting for year of birth, previously found to be important in, for example, suicide research. 34

Our study has 2 main findings. First, the association between schizophrenia and violent crime is minimal unless the patient is also diagnosed as having substance abuse comorbidity. Among patients without comorbidity, adjusted ORs from comparisons with unrelated general population controls or unaffected siblings were 1.2 to 1.3. It is possible that these risk increases would change if more sensitive measures than discharge diagnoses of substance abuse had been used. A recent study based on the National Epidemiologic Survey on Alcohol and Related Conditions (NESARC) also found no association between schizophrenia (with or without comorbid substance abuse) and any violence or serious violence, although this was based on 294 individuals with schizophrenia and may have been underpowered to detect any differences across groups. However, when all patients in the NESARC study were examined, substance abuse comorbidity did increase the risk of violence in those with mental disorder. 35 Although the NESARC sample included more than 18 times more individuals with depression than with schizophrenia, it suggests that similar mechanisms to that we found may mediate violent offense in other mental disorders. Expert opinion has suggested that schizophrenia increases the risk 4 to 6 times in men and possibly even more so in women. 1 , 31 However, these increased risks are not as relevant to individuals without comorbid substance abuse; hence, our findings suggest that assessment and management of violence risk should be prioritized in patients with schizophrenia and substance abuse comorbidity. Whether it is necessary to assess violence risk in all patients, as recommended in the current guidelines of the American Psychiatric Association with “substantial clinical confidence,” the highest category of evidence, will depend on a variety of individual and local factors, including service provision. 36 On the other hand, our data concur with the importance of effective psychiatric treatment from a public health perspective 37 and the importance of evidence-based prevention strategies for dealing with substance abuse. 38

The second main finding is the variation in violence risk depending on the degree of relatedness between the patient and the control group. Compared with unrelated general population controls, the risk of violent crime in individuals with schizophrenia and substance abuse comorbidity was increased 4-fold (OR, 4.4; 95% CI, 3.9-5.0). However, unaffected siblings had increased rates of substance abuse compared with unrelated general population controls, which meant that the risk increase for schizophrenia with substance abuse comorbidity compared with these siblings was substantially reduced (OR, 1.8; 95% CI, 1.4-2.4), suggesting familial confounding of this association. Familial confounding may occur through genetic susceptibility or early environmental effects.

This finding is consistent with 4 possible explanations for the increased risk of violence among patients with schizophrenia compared with general population controls. First, it is possible that schizophrenia (with a predominantly genetic etiology) leads to substance abuse, which in turn increases the risk of violent criminality. Some limited support for this interpretation was found from the timing of substance misuse in relation to hospitalization for schizophrenia. We found that the risk of violent crime was higher when substance abuse was diagnosed after compared with before hospitalization for schizophrenia. However, considerable caution is warranted: the reliability of diagnoses of substance abuse in Swedish hospital registers is fair to moderate and information on timing is suboptimal since it requires inpatient treatment. Second, genetic susceptibility to substance abuse might lead to schizophrenia, which in turn increases the likelihood of violent behavior. A third possibility is a genetic susceptibility to schizophrenia in common with substance abuse and that both in turn are associated with violence. A final interpretation is a shared genetic susceptibility to substance abuse, schizophrenia, and violent criminality. Some support for the latter comes from longitudinal studies that have found that violence and serious aggression precede the diagnosis of schizophrenia, 39 , 40 even after controlling for preadolescent psychotic symptoms. 40 Although our data do not suggest one interpretation above the others, future work is necessary to establish the mechanisms responsible for the associations among substance abuse, schizophrenia, and violence. One promising approach would be to use molecular genetic studies, wherein a host of putative genetic markers exist. 41 Regardless of the nature of the mechanism, adequate substance abuse treatment for individuals with schizophrenia is likely to reduce the risk of violence and should be part of the routine assessment and management of all such patients. Within a sample of individuals with schizophrenia, a recent US prospective investigation has confirmed the importance of substance abuse in predicting violence in patients with schizophrenia and also found that childhood conduct problems are a strong predictor. 42 However, the risk of violence in schizophrenia with childhood conduct disorder compared with general population controls remains uncertain.

Study weaknesses include our reliance on hospital data for case ascertainment and comorbidity. Over a 30-year period, more than 90% of individuals in Sweden with schizophrenia will have been hospitalized at some point. 16 However, since we used 2 diagnoses of schizophrenia for inclusion, some individuals with schizophrenia would not have been included in our sample. Another weakness is that information on comorbidity was also based on hospital diagnoses, and it is likely that the effects of substance abuse have been underestimated. However, as the same approach was taken for cases and controls, this may not affect risk estimates if a similar degree of underestimation occurred. Although we relied on conviction data, other work has shown that the degree of underestimation of violence is similar in psychiatric patients and controls compared with self-report measures; hence, the risk estimates were not affected. 43 A further limitation is that we did not have data on whether treatment was received and the nature of such treatment. It is possible that treatment effects mediated some of the differences found herein. Recent work has shown that antipsychotic medication reduces the incidence of any violence over 6 months from 19% to 14%, although that investigation was underpowered to assess serious violence. 42 However, with median times to violent offense in the current study being around 3 years after hospital discharge, studies assessing the impact of treatment will need extended follow-up. Rates of violent crime and their resolution are similar across Western Europe, suggesting some generalizability to our findings. 44 Comparisons with the United States are more difficult due to differences in legal and judicial systems, but information on assault rates has been collected for 1981-1999. Police-recorded assault rates were 3.7 per 1000 population in the United States and 4.1 per 1000 in Sweden in 1981-1999. 45

We conducted a number of sensitivity analyses to explore factors that could potentially influence the risk estimates. We found no changes to risk estimates when a more severe definition of violent crime was used or the criteria for case ascertainment for schizophrenia was 1 hospital discharge diagnosis rather than 2. Increasing the length of follow-up through 2006 provided further evidence of familial confounding in the association between schizophrenia and violent crime and the role of substance abuse comorbidity in increasing the risk. Further research is necessary to clarify temporal trends in violent offense in these patients, and alternative designs, such as interrupted time series analysis, should be considered.

One of the implications of these findings is in relation to stigma. The public perception of the dangerousness of psychiatric patients is pervasive and is a key factor in their stigmatization, 46 partly influenced by selective media coverage of high-profile cases. 47 As a consequence, some western governments have introduced specific laws for offenders who have mental disorders that focus on the assessment of dangerousness and public protection. 48 Moreover, the stigma of mental illness is considered to be the most significant obstacle to the development of mental health care. 49 Our findings on the mediating role of substance abuse and the marginally increased risk of violent offense in patients without substance abuse should contribute to a more informed debate about stigma in psychiatric patients.

In summary, we used longitudinal designs to investigate the risk of violent crime in patients with schizophrenia. Our study substantially increases the evidence base by including more individuals with schizophrenia than the previous studies combined and more precise methods to handle confounding. We demonstrate that the risk of violent crime in schizophrenia in patients without comorbid substance abuse is only slightly increased. In contrast, the risk is substantially increased among patients with comorbidity and suggests that current practice for violence risk assessment and management in schizophrenia may need review.

Corresponding Author: Seena Fazel, MD, University Department of Psychiatry, Warneford Hospital, Oxford OX3 7JX, England ( [email protected] ).

Author Contributions: Dr Fazel had full access to all of the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.

Study concept and design : Fazel, Långström, Grann, Lichtenstein.

Acquisition of data : Fazel, Långström, Hjern, Lichtenstein.

Analysis and interpretation of data : Fazel, Långström, Hjern, Grann, Lichtenstein.

Drafting of the manuscript : Fazel, Lichtenstein.

Critical revision of the manuscript for important intellectual content : Fazel, Långström, Hjern, Grann, Lichtenstein.

Statistical analysis : Fazel, Grann, Lichtenstein.

Obtained funding : Långström, Lichtenstein.

Administrative, technical, or material support : Hjern, Lichtenstein.

Study supervision : Fazel.

Financial Disclosures: None reported.

Funding/Support: The Swedish Research Council–Medicine and the Swedish Council for Working Life and Social Research funded the study.

Role of the Sponsor: The funders had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; or preparation, review, or approval of the manuscript.

Additional Contributions: We are grateful to Eva Carlström, MSc, Karolinska Institutet, for assistance with data extraction in this project, and to Helen Doll, DPhil, University of Oxford Department of Public Health, for statistical advice. Ms Carlström and Dr Doll did not receive specific compensation for their work with these data.

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The Mental Elf

Schizophrenia and violent crime: perpetrators or victims.

The link between violent acts and severe mental disorder has been proposed for a long time (Lindqvist & Allebeck, 1990). Quantitative methods have largely confirmed this relationship. For instance, most studies show that violent crime is around 2-10 times more common among individuals diagnosed with schizophrenia than compared populations (Fazel et al, 2009).

Moreover, a recently published study also indicates that individuals with schizophrenia were much more likely to be convicted of a violent crime in comparison to those who were not.

So…what are we to make of all this?

Violence is common. There were 1.3 million incidents of violence reported in England and Wales between July 2013 and June 2014 according to the Crime Survey of England and Wales (ONS, 2013).

Schizophrenia, although rare, with a median incidence of just around 15 cases per hundred thousand of the population per year, is as yet incurable and persists in people, resulting in a relatively high prevalence (McGrath et al, 2008).

There has been a consensus that violence risk is increased in schizophrenia. Much of this research was summarised in a meta-analysis in 2009 (Fazel et al, 2009). It reported an average four-fold increase in violent crime in men with schizophrenia, compared to men without schizophrenia.

However, many older studies were considered small and methodologically limited. They were also seen as unable to adequately assess the temporal relationship between schizophrenia and violence.

The Crime Survey of England and Wales reported over 1.3 million incidents of reported violence between July 2013 and June 2014.

Last October saw the publication of another study in this area, this time in the journal Psychological Medicine (Fleischman, 2014). The investigators identified hospitalisations for schizophrenia using an Israeli case registry.

These cases, numbering more than three thousand, were compared to an age- and gender- matched comparison group on their exposure of interest, which was having committed a violent crime. Information on this was gathered from police records, to which the case registry data was linked.

Logistic regression was used to assess the relative difference in the prevalence of violent offences in cases compared to controls, after accounting of alternative explanations for the difference, including age, gender, marital status, family structure, and substance misuse.

Although the full statistical model is not presented, the report states that schizophrenia still had a significant effect on violent crimes, after accounting for confounding by the other variables.

Schizophrenia has quite low incidence (15 cases per 100,000 of the population per year) but a high prevalence. People with schizophrenia have a two- to threefold increased risk of dying.

The study linked the Israeli population registry with a separate register of psychiatric hospitalisations. Within the case register, the case series for analysis were defined as those individuals admitted to any psychiatric ward born after 1970.
For each case identified, the population register was used to identify their parents and all their siblings. For each case of sibling and parent identified, four controls were identified from the population register at random.
Sociodemographic information and details of crimes committed was gathered for both cases and controls. Violent crimes were defined as murder, attempted murder, assault, rape, threats and robbery.
Half-siblings were excluded. Where there were families with more than one case eligible for inclusion, one was selected at random.
Differences in the prevalence of criminal conviction were assessed between cases and controls.
Logistic regression was used to adjust for age, gender, marital status, parity, substance misuse, and suicide attempts. This accounted for differences in conviction prevalence (other than the diagnosis).
There was an increased risk of criminal activity with schizophrenia, peaking at around the time of the first admission.
Overall, violent crimes were 4.3 times more common in cases compared to controls , and 2.8 times more common in cases compared to unaffected siblings .
There were also associations with sex-related and drug-related crimes .
male gender
substance misuse
multiple hospitalizations (more than four)
having violent parents
having a suicide attempt
having a sick family member.

People with schizophrenia were more likely to have committed an offence and this association was strongest for violent crimes.

People with schizophrenia in this Israeli study were more likely to have committed an offence and this association was strongest for violent crimes.

Conclusions

The study found that individuals with schizophrenia were more likely to have committed an offence, an association which was strongest for violent crimes, but which pertained also for sex- and drug- related crimes.

This was consistent with previous evidence, although the authors pointed out that there are relatively few previous studies. The authors also pointed out that the association with sex-related crimes goes contra to some of the literature. They do not address possible explanations for this phenomenon in their data, e.g. confounding or measurement bias.

This study demonstrates an association not only between schizophrenia and subsequent crime, but also with crimes committed prior to the index admission, bolstering the idea that individuals who go on to be diagnosed with illness later in life exhibit behavioural differences to the rest of the population.

As expected, individuals who had a large number of admissions were at greater risk of being convicted for a violent crime – implying either more severe illness resulting in more severe behavioural disturbance, or more behavioural disturbance leading to more recent admissions.

People with schizophrenia and a large number of hospital admissions were at greater risk of being convicted for a violent crime.

This Israeli research found that people with schizophrenia who had also had a large number of hospital admissions were at greater risk of being convicted for a violent crime.

Strengths and limitations

The authors, in their discussion of the limitations of the work, refer to:

the inability to calculate the impact of schizophrenia on crime rates,
the lack of socioeconomic information in their analysis,
the possibility that the measures of substance misuse were vulnerable to reporting bias, because they were based on self-report information.

As a reader, the analysis is well conducted and based on an enormous dataset- the effect of chance on this dataset is likely to be limited.

However, the absence of any socioeconomic information on the cases or controls is a big problem. We know that there is probably a causal relationship between low socioeconomic status and criminal activity – if anything it is the most widely agreed upon cause!

The study was missing socioeconomic information about the cases or controls, which is a real weakness.

And we, of course, also know that a very strong correlation exists between social position and schizophrenia (Wicks et al, 2005). The differences observed in this study between convicted and non-convicted subjects may lie not in whether or not they have been diagnosed with schizophrenia, but rather in the fact that those convicted are likely to be poorer, less well educated and less employed.

Thus, the authors leave an important competing explanation for their results unexplored. This is unfortunate.

The authors point out that there is a consensus that schizophrenia is associated with offending, and that therefore this should involve practice in the assessment, treatment and monitoring of patients.

I think, however, that this work reflects a traditional bias in the issues that psychiatric research has concerned itself with, focusing on the ill as perpetrators rather than victims. I think the changes that should be made as a result of this research should be a keener focus on individuals with the diagnosis of schizophrenia as victims, including prior to the onset of illness.

Over-emphasis on the risk of violence is a grave disservice to many suffering from a debilitating but treatable illness.

Fleischman A, Werbeloff N, Yoffe R, et al. Schizophrenia and violent crime: a population-based study. Psychological medicine 2014;44(14):3051-57. [ Abstract ]

Lindqvist P, Allebeck P. (1990) Schizophrenia and crime. A longitudinal follow-up of 644 schizophrenics in Stockholm. The British Journal of Psychiatry 1990;157(3):345-50 [ Abstract ]

Fazel S, Langstrom N, Hjern A, et al. (2009) Schizophrenia, substance abuse, and violent crime . JAMA – Journal of the American Medical Association 2009;301(19):2016-23.

ONS (2013). Crime in England and Wales, Year Ending June 2013 . Office for National Statistics.

McGrath J, Saha S, Chant D, et al. Schizophrenia: a concise overview of incidence, prevalence, and mortality . Epidemiologic Reviews 2008;30(1):67-76

Wicks S, Hjern A, Gunnell D, et al. (2005) Social adversity in childhood and the risk of developing psychosis: a national cohort study. Am J Psychiatry. 2005 Sep;162(9):1652-7. [ PubMed abstract ]

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RT @Mental_Elf: Schizophrenia and violent crime http://t.co/8DTH6bwZ2z

Schizophrenia and violent crime: perpetrators or victims?: Debut blogger Vishal Bhavsar summarises an Israeli … http://t.co/ORWTDopNXy

@Mental_Elf great blog,further factor might be gender bias by those assessing acts of violence i.e. male=overestimate & female=underestimate

@Mental_Elf yes socioeconomic data missing, but how diagnosed & treated in different countries not included also which impacts on findings

@Mental_Elf Would like to see head/head comparison between males w/ & w/out Sch diagn who misuse subst, from violent backgrounds.

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@Mental_Elf Don’t think lack of socio-economic variables is a big limitation as the use of sibling comparisons will account for this

@seenafazel @Mental_Elf I think just assuming no variation exists by the confounder isn’t really dealing with it!Could have been explored..

@seenafazel @Mental_Elf also,argument that SES is unrelated to violence in Sz in Sweden, and therefore an unimportant confounder is risky!

@DrVishalBhavsar @Mental_Elf Absolutely, which is why using sibling controls is so powerful. Adjusting for SES using proxies will be partial

@seenafazel @Mental_Elf What’s importan’s that SES is prob. causally related to violence @ the population level,making it a prob. confounder

@DrVishalBhavsar @Mental_Elf agreed. It is a confounder. Sibling controls powerful way to account for it. See http://t.co/SpxOQMqFNf

@Mental_Elf See the paper by Mullen on the need to take perpetration in scz patients seriously to improve outcomes: http://t.co/oxx8ObYbHJ

@Mental_Elf Relative risks incorrectly reported. Compared to pop controls, scz increases odds of violent crime 4.3; compared to sibs, 2.8

Schizophrenia and violent crime: perpetrators or victims? http://t.co/aH8WMEtzhS

Today @DrVishalBhavsar summarises an Israeli study that explores the links between schizophrenia & violent crime http://t.co/8DTH6bOAr9

Mmm interesting

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Interesting

Over-emphasis on the risk of violence is a grave disservice to people with schizophrenia http://t.co/8DTH6bOAr9

@Mental_Elf I agree. My local paper has more reported incidents of violence due to alcohol misuse then due to those suffering with a MI!

@Mental_Elf 1. Where rates of victimization and perpetration of violence are reported in the same samples, these are not very different

@Mental_Elf 2. See table 2 in 2014 systematic review on victimization in SMI: (table 2) http://t.co/hhptmTc5jG

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Mental Elf: Schizophrenia and violent crime: perpetrators or victims? http://t.co/byXGJWgya6

Schizophrenia and violent crime: perpetrators or victims? http://t.co/TEmp40ZKx7 via @sharethis

Don’t miss: Schizophrenia and violent crime – perpetrators or victims? http://t.co/8DTH6bOAr9

RT @Mental_Elf: Schizophrenia and violent crime perpetrators or victims? http://t.co/SOUJ3FLy6r <– V.important “Strengths and limitations”

‘ #Schizophrenia ‘ and violent crime: perpetrators or victims? http://t.co/12H6Drq3yv

Don’t miss Schizophrenia and violent crime – perpetrators or victims? #HLT301 http://t.co/MFZW8urZ1T

Surely using relatives as controls does partially control for socioeconomic factors except 4 illness impact on these? http://t.co/VQUEkP9MwK

#Schizophrenia and violent crime: perpetrators or victims? http://t.co/ZdcKn4t3JZ #MentalHealth via @Mental_Elf

For the ones who’s symptoms are controlled by medication if they refuse to take them they should be put in prison

I agree that deviant behavior (madness) is a clinical feature of many individuals with schizophrenia. However, the word “violent” may just be a reflection of post-1970 Israeli psychiatry. Place an individual in a ghetto and of course they are going to commit violent crime. Let’s create a society where these individuals belong.

Hi, I am a student from a high school in Australia that is currently studying year 10 psychology. I like your information and will definitely reference you in my extended informative essay. I was wondering if you have any more resources and references that you would recommend I use. The claim I have been asked to speak about is, “adults are more likely to engage in deviant behaviour if they suffer from an abnormality of the mind”. I have written an essay focus question of, “what are the most common abnormalities of the mind that may lead adults engaging in deviant behaviour?” do you think you would be able to help me out?

kind regards- Noelle

Are you saying that more Schizophrenia sufferers commit violent crimes than the general population, or a Schizophrenia sufferer is more likely to commit violent crimes than the general population. there is a difference. One of these tars with the same brush all schizophrenia sufferers, and the other doesn’t.

Absolutely not – this is really important. Big studies like this focus on working out what is happening on average, and cannot tell you directly what is going to happen to a given individual.

Does anybody think that institutions should be used to provide secure places to treat sufferers , thereby protecting the patients and the public at large saving a lot of grief for both parties ?

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Lawmaker Is Left With ‘Lifetime Trauma’ as Attacker Pleads Guilty

Andrey Desmond pleaded guilty to three felony charges this week in the attack on Maryam Khan, a member of the Connecticut House of Representatives, last June.

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A portrait of Maryam Khan, wearing a dark blazer and a pink hijab, stands in a dim wood-paneled room looking toward the camera with a serious expression.

By Erin Nolan

It has been nearly 10 months since a man attacked Maryam Khan, the first Muslim elected to the Connecticut House of Representatives, outside an Eid al-Adha prayer service in Hartford, Conn. She is still struggling to heal, she said.

“I have a lot of things to get through, both emotionally and physically,” Ms. Khan said. “I’m still working on trying to heal and process what happened.”

But she felt some closure in a courtroom on Tuesday, she said, when she watched her attacker plead guilty to felony charges related to the attack.

The man, Andrey Desmond, 30, of New Britain, Conn., pleaded guilty to attempted third-degree sexual assault, strangulation and risk of injury to a child, according to the clerk’s office at the State Superior Court in Hartford.

“He claimed to understand what was happening, and for me, personally, it was helpful to be there and to witness that,” Ms. Khan said.

Under the terms of a plea agreement, Mr. Desmond is required to serve five years in prison, register as a sex offender and receive mental health treatment after he is released. His sentencing is scheduled for June 4.

The attack occurred on June 28, after a morning prayer service hosted by the Islamic Center of Connecticut and held at the XL Center, an arena and conference center. Ms. Khan was taking pictures with her family, including her three children, outside the arena when Mr. Desmond approached and made numerous suggestive and threatening comments, she said.

When Ms. Khan tried to walk away, Mr. Desmond put his arm around her neck, tried to kiss her, slapped her across the face and threw her to the ground, the police said in June.

Ms. Khan thought she was going to die during the attack, she said on Wednesday.

After the attack, Mr. Desmond tried to run away but was chased down by bystanders and held until the police arrived and arrested him.

Some Muslim groups and state lawmakers, including Ms. Khan, initially called for Mr. Desmond to be charged with a hate crime, but after an investigation hate crime charges were not added.

Ms. Khan said she still wondered why Mr. Desmond targeted her and her family.

“I don’t think it was totally random,” she said. “I think there was something about us, I don’t know what, that made him think it was easy to accomplish what he wanted to with us.”

Mr. Desmond had been diagnosed with schizophrenia before the attack and has a long history of psychiatric hospitalizations and time in inpatient facilities in New York and Connecticut. He was released from prison in 2020 and placed under intensive monitoring under Kendra’s Law, New York’s court-ordered outpatient treatment program for people with severe mental illness who are most at risk of committing acts of violence.

By the spring of 2023, it was clear that the nonprofit contractor assigned to coordinate the man’s care was not responding promptly to signs that he was unraveling. Just weeks before the attack, in conversations with a reporter as part of a New York Times investigation into the Kendra’s Law program, Mr. Desmond described delusions, saying he sometimes thought that people were “raping” him in his sleep. “They think things are going to turn out well? If this country puts me out on the street?” he asked.

Mr. Desmond left his housing program in the Bronx that May and returned to Connecticut, where he grew up. For weeks, his mother tried to reach a member of the team coordinating his care, calling and texting frantically to ask the worker to find her son. Days after her last text went unanswered, he attacked Ms. Khan.

Aaron Romano, Ms. Khan’s lawyer, called the situation “a confluence of tragedy.” He said Mr. Desmond was exhibiting signs of severe mental illness at the time of the attack, but that a court-ordered evaluation determined Mr. Desmond was competent to stand trial.

The violent episode “highlights just how broken our mental health system is and how the brokenness of that system turns other people in society, like me and my children, into victims,” Ms. Khan said. She said that she was exploring the issue of mental health treatment in Connecticut as she looked toward the next legislative session.

Ms. Khan said Mr. Desmond had left her and her children with “a lifetime trauma.”

“I think this is going to be something that sticks with them for a long time,” she said of her children, who were 10, 12 and 15 at the time of the attack. “Even when we go out in public and they hear a man yelling, my children immediately have panic attacks. They can’t sit in spaces where people are yelling.”

Still, she said, her feelings toward Mr. Desmond are complicated. He is the product of a “revolving door system” that “puts people back on the street even though they don’t know how to take care of themselves yet,” she said.

“If he had received proper care, we may not have been here,” she said.

Jan Ransom contributed reporting.

Erin Nolan is a reporter covering New York City and the metropolitan region. She is a member of the 2023-24 Times Fellowship class. Email her at [email protected] . More about Erin Nolan

Politics in the New York Region

A Jail Project: The demolition of a Manhattan jail complex in Chinatown to make way for a bigger one has damaged a neighboring building and raised concerns about years of dust and disruption.

Adultery as Crime: An antiquated but seldom-enforced state law categorizes adultery as a crime, and past efforts to repeal it have gone nowhere . But that seems poised to change.

Limiting Social Media’s Hold: New York’s governor and attorney general joined forces to pass a law trying to restrict social media companies’ ability to use algorithms to shape content for children. Big Tech is putting up a battle with a high-stakes lobbying effort.

Targeting Trans Athletes: A proposed ban on transgender women playing on women’s sports teams has turned a Long Island county into the latest battleground for conservatives who have put cultural issues at the center of a nationwide political strategy.

Illegal Donations: A Chinese business titan pleaded guilty to federal charges that he made more than $10,000 in straw donor contributions to political candidates — including, a person familiar with the case said, to a New York congressman and Mayor Eric Adams.

A Cannabis Mess: Gov. Kathy Hochul has ordered officials to come up with a fix for the way New York licenses cannabis businesses amid widespread frustration over the plodding pace of the state’s legal cannabis rollout.

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There has been a consensus that violence risk is increased in schizophrenia. Much of this research was summarised in a meta-analysis in 2009 (Fazel et al, 2009). It reported an average four-fold increase in violent crime in men with schizophrenia, compared to men without schizophrenia.
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Fazel et al. (5) showed that patients with schizophrenia had a 1.2 increased risk for violent criminal acts compared to the general population, but substance abuse comorbidity increases the risk ...
Study on the association between schizophrenia and violence
Interestingly, the chance of developing Schizophrenia among those with a history of violent crime is approximately five times greater than those committed non-violent crime only (Gosden et al., 2005). Thus, individuals with Schizophrenia contribute to a disproportionate rate of violent crimes. Typologies of Offenders with Schizophrenia
Schizophrenia and Crime
Schizophrenia and Crime - Volume 157 Issue 3. To compare the crime rate of schizophrenics with that of the general population, data from the Central Swedish Police Register on 790 schizophrenic patients discharged from hospitals in Stockholm in 1971 was analysed for the period 1972-86.
Current Concepts and Treatments of Schizophrenia
Abstract. Schizophrenia is a debilitating mental illness which involves three groups of symptoms, i.e., positive, negative and cognitive, and has major public health implications. According to various sources, it affects up to 1% of the population. The pathomechanism of schizophrenia is not fully understood and current antipsychotics are ...
Schizophrenia Essays
This essay is about schizophrenia and the opposite outcomes it has, and the argument sources to the subject. The topic at hand has the downsides of hallucinations, delusions, as well as emotional and mental behaviors. ... This complex relationship between schizophrenia and crime raises important questions about the intersection of mental health ...
The Relationship Between Schizophrenia and Criminality
Schizophrenia spectrum disorders are usually associated with a substantially increased rate of violent crimes, in comparison to the general population. The risk factors include the same as in the general population, with a social and family background, and also specific risk factors found in schizophrenic patients like delusional and ...
Schizophrenia and Moral Responsibility: A Kantian Essay
In fact, Kant wrote extensively and in great detail about mental disorder. But despite its prominence in the Anthropology and the Essay on the Maladies of the Head, Kant's account of mental disorder has gone unnoticed even among scholars who devoted their work to Kant's anthropological works. 3 This paper is an attempt to fill the gap. My ...
Lawmaker Is Left With 'Lifetime Trauma' as Attacker Pleads Guilty
Mr. Desmond had been diagnosed with schizophrenia before the attack and has a long history of psychiatric hospitalizations and time in inpatient facilities in New York and Connecticut. He was ...

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Evidence Supports Link Between Schizophrenia, Violent Crime

Recent Studies Confirm Heightened Risk

Police Liaison Formed

Schizophrenia and Criminal Responsibility: A Systematic Review

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Research on interpersonal violence in schizophrenia: based on different victim types

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The Social Disability Screening Schedule(SDSS)

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Multinomial logistic regression analysis

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BMC Psychiatry

Schizophrenia and Crime

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Lawmaker Is Left With ‘Lifetime Trauma’ as Attacker Pleads Guilty

Politics in the New York Region

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