1.1. The impact on victims, family and society as a whole: caregiver and public health role

The primary focus of mental health professionals is helping people in need. Within this context this means trauma-related working with the victims and their families. However, mass violence is not only an individual experience. One of the main goals of the perpetrators, specifically in the case of terrorism, is to instill at the population level a feeling of fear, uncertainty and vulnerability. It is as yet unclear what consequences this has on the population’s mental health and its most vulnerable individuals. From this perspective, terrorism and mass violence is a topic that needs to be addressed by public (mental) health research and strategies [Reference Alcala, Sharif and Samari1].

1.2. The stigmatization effect of the association between violence and mental illness: advocacy and communicator role

Mass media play a powerful role in shaping perception, understanding and public discourse surrounding key issues that affect audiences [Reference Defoster and Swalve2]. Media have an extremely powerful role in the creation of a public image and their remains a real threat that violent acts are disproportionally framed with an association of having a mental health disorder. Likewise, most Americans fault mental health systems for failing to prevent shootings, showing a poor understanding of how mental health and illness can be related to violence, and how individual responsibility is not necessarily absent in such incidents, even if mental illness were to be a relevant factor; it is unlikely to be the sole factor. There is a clear shift over the last 20 years suggesting that reform of the mental health system is the solution rather than reform of gun policy, guns being the top cause of mass shootings [Reference Defoster and Swalve2]. This media framing tends to galvanize public attention and emphasize the ostensible link between mental illness and violence. This contrasts with the epidemiological reality that the majority of the severely mentally ill individuals never become violent. On the contrary, mental illness is strongly linked with being a victim and increased risk of suicide, a manner of death that accounts for more than half of the firearm-related deaths annually in the US [Reference Swanson, Mcginty, Fazel and Mays3, Reference Defoster and Swalve2]. In this sense, media framing of mass violence blames these events on breakdowns in mental healthcare and policy, obscuring the much more complex experiences of mental illness, and scapegoating the mentally ill for shocking acts of public violence [Reference Defoster and Swalve2].

Mental health professionals must show leadership, and work with patient- and family representatives, and the media to develop strategies to counteract this stigmatizing framing.

1.3. Research into the motives of mass violence and the relation with mental health: role as a scientist

The relation between violence and mental health problems remains a delicate debate. On the one hand, there is the lingering danger of stigmatization. On the other hand, there are situations were violence risk and mental disorder are indeed interrelated. Delusions or command hallucinations, suicidality or psychopathy, often within the context of co-occurring substance abuse, can lead to violence. These pathways need better scientific understanding and balanced public information [Reference Sheehan4]. We are not able to apply the same level of understanding yet to the varieties of motivation for terrorism related homicide, the majority of which are unrelated to mental illnesses. The relationship between mental health, psychopathology and radicalization or terrorism is complex and remains poorly understood. Faced with sudden, seemingly inexplicable acts of aggression stemming from individuals or groups, our first reflex is often to seek an explanation in possible underlying mental disorders [Reference Bhui, James and Wessely5]. This quasi automatic association not only harms and stigmatizes many people with mental problems but also impairs a thorough and objective analysis of the real causes, which are highly complex, idiosyncratic, and often differ from case to case.

The limited data we have on this topic shows that organized terrorist groups and individuals who have committed violent terrorist acts are rarely associated with an increased prevalence of mental disorders. Moreover, terrorist groups and networks seem to avoid recruiting people with mental health problems. They may even stigmatize people with mental problems, thinking that they are unreliable, difficult to train and direct to avoid detection [Reference Bhui, James and Wessely5]. In contrast, lone-actor mass violence may be more associated with psychopathology. This type of frequently grievance-fueled targeted violence includes also public figures assassins, school shooters and workplace attackers. These forms of violent acts share important characteristics and risk factors, with among others severe mental illness [Reference Hurlow, Wilson and James6]. Indeed, up to 43% of the lone-actor terrorists have been reported to have a history of mental illness, albeit without connection to specific disorders [Reference Corner and Gill7, Reference Bhui, James and Wessely5].

As part of the process of radicalization, emerging evidence shows that mental disorders affect susceptibility to radicalizing influences. Radicalization is a process by which an individual or group comes to adapt increasingly extreme political, social or religious ideas and aspirations that reject or undermine the status quo. A lack of identity, empowerment, attributing significance, an unmet need of connection – a sense of belonging, all prove key concepts as the breeding ground for a wide range of human problems, including the risk of radicalization [Reference Coid, Bhui, MacManus, Kallis, Bebbington and Ullrich12]. Of importance, the same elements constitute vulnerabilities for numerous “public health” issues such as (chronic) poor physical health, substance abuse and mental health problems such as depression [Reference Bhui, Warfa and Jones8]. It is striking that in several studies, depression was associated with terrorist sympathizing [Reference Bhui, Everitt and Jones9]. This may reflect a pessimistic outlook and negative world view of how to resolve grievances or life’s problems through non-violent social and political engagement and actions.

From another angle, some authors point to untreated mental illness as a possible contributor to violent crime, and argue that the decline in the availability of long-term, intensive mental health hospitals might have negative impacts on firearm-related deaths and possible on the incidence of mass shooting events in the US [Reference Meszaros10]. Taken together, the challenge facing mental health professionals is to develop better knowledge on this topic. However, given the delicacy of this topic and the strong public opinion, media framing, securing funding for research in this area proves difficult. Exemplary is that, due to political pressure, for a long period research on the relation between gun violence and mental health has been withheld by the Centers for Disease Control and Prevention (CDC) [Reference Defoster and Swalve2].

1.4. Therapeutic relation versus the role of screening on radicalization and terrorism: professional confidentiality and boundaries

Although the core role of any mental health professional is the care for his/her patients and families, other roles of the psychiatrists concern the protection of society from violence resulting from mental illness and preventing individuals with mental illness from ruining their lives by becoming involved in serious criminal acts and, overall from becoming victims of criminal (aggressive) acts towards themselves [Reference Hurlow, Wilson and James6]. From this perspective, there is a growing societal pressure on health professionals to take on an active role in screening for signs that potentially can identify future perpetrators of violence. This may ultimately result in mandatory reporting to authorities, e.g. the UK Government Prevent strategy. However, some doctors might voice concerns that the focus on screening, and possible protocols associated with it, would potentially stigmatize already marginalized groups and fundamentally compromise confidentiality for patients. Clearly guidance is needed in mental health practice in the delicate balance of assessing risk danger and deciding when breaching confidentiality in the interest of wider public health and danger.