Recent events, including the arrest of two teenage school pupils in rural South Australia charged with weapons offences but reportedly planning a school attack, and the tragic death of 17 pupils at Marjory Stoneman Douglas High School in Florida, have reawakened awareness of these rare, but devastating, events. These events also highlight the possibility that a school shooting might be successfully carried out in Australia or New Zealand.

In New Zealand in 1923, a father shot and killed two pupils at his children’s school, wounding the school master and five other children. Accounts suggest he had a grievance towards the school and was known in the community for persecutory ideas. In 1999, Jonathan Horrocks killed one and injured another in a shooting in a bar at La Trobe University, Melbourne. He was restrained from harming others. He reportedly held a grudge, having been sacked earlier that year on suspicion of theft. He received a life sentence with a minimum term of 23 years. In 2002, Huan Yun Xiang killed two and injured five at Monash University, Melbourne. The attack was reportedly driven by persecutory delusions centred on another student, who was one of the two to die. A mental impairment defence was accepted by the jury, and Xiang was admitted to a forensic hospital. In Australia, there have been three other incidents of students using firearms or explosives on school grounds, without fatalities.

The literature on school shootings (Langman, 2015) is generally restricted to circumstances where the perpetrator is a current, or recent, pupil at the school or University and attends with the specific intention of committing a massacre, rather than gun violence in schools generally. Applying this definition, the NZ and La Trobe cases would not be categorised as typical ‘school shootings’. School shootings comprise part of a group best termed lone actor mass killers.

What do we know about school shooters? Newman and Fox (2009) identified five necessary conditions, although they are not regarded as sufficient to culminate in a shooting. These are Marginalisation;

Psycho-social problems;

Cultural script;

Availability of guns;

Failure in prevention and surveillance systems. Ready availability of firearms correlates with higher prevalence of school shootings. Two thirds of US school shooters accessed firearms at home or the home of a relative. In Australia, after the 1996 Port Arthur massacre, the government offered a gun amnesty/buy-back and introduced legislation restricting ownership and use of self-loading rifles and shotguns. These changes are credited with reducing firearm-related homicides.

Common elements of school shooters Case series of school shooters have identified common themes; acknowledging that there is no simple explanation for a complex and rare phenomenon. The majority are adolescent males. A study of seven German school shooters found that four were classified as loners and in five cases, people around them were worried about them, contrary to the myth that such events occur ‘out of the blue’. Most had an interest in weapons or militaria and all had made threats to bring weapons into school or displayed weapons to others. The majority had an interest in previous school shooters, and all were interested in violent media. All had a negative perspective about the future and narcissistic fantasies were common. A series of three Finnish school shootings, culminating in 25 deaths (excluding the perpetrators), revealed similar patterns. The perpetrators had few friends, were bullied and were described as having untreated psychological problems. All were active on the Internet, with aggressive online identities; they received encouragement from online communities glorifying school shootings. Other studies have identified common themes. Personality characteristics tend to include narcissistic, paranoid or antisocial traits. Other common features include bigotry, alienation or peer rejection, low self-esteem, feelings of rejection, depression or suicidal ideation, being bullied, and having grievances against the school. There is conflicting evidence regarding substance abuse. Perpetrators lacked a history of violent behaviour; previous violence is often seen as having the strongest correlation with future violence so assessors could be lulled into discounting future risk.

The cultural script and the role of the Internet There are often consistent elements to school shootings. The 1999 Columbine killers, Harris and Klebold, portrayed themselves as antiheroes, opining (in recordings they left behind) that they would gain respect for their actions and start a revolution. Mullen (2003) introduced the concept of a social and cultural script in his paper on the autogenic massacre. The Internet and other media have been widely used by perpetrators to publicise and explain their actions. They are keen to take responsibility, or ‘credit’ for their actions. Web pages and YouTube videos displaying violent fantasies and threats are common. Seung-Hui Cho sent a videotape to a news channel before killing 32 people and wounding a further 17 at Virginia Tech, 2007. Many incidents have developed from a violent fantasy life, lived out online or within other media, escalating into a realisation that they could perpetrate such an attack. There is a phase of preparation and planning, sometimes with a final crisis, before the fatal action. Perpetrators often undertake most of their planning online, encouraged by social networking communities of like-minded individuals. Their on-line communications also reference industrial music, violent videogames, revolutionary philosophy and previous rampage killers. They have a fascination with previous shootings, and Towers et al. (2015) suggest that the increase in school shootings since Columbine may be due to contagion and glamorisation of previous incidents.

Leakage Leakage is communication to third parties of intention to do harm; ‘when a student intentionally or unintentionally reveals clues to feelings, thoughts, fantasies, attitudes, or intentions that may signal an impending violent act’ (Meloy and O’Toole, 2011). The method of communication varies; verbal statements of intent, letters or diaries, schoolwork, online admissions in social media, videos or sound recordings. Leakage is a warning behaviour that can precede a targeted act and therefore contributes to structured professional judgement, potentially enabling intervention. While not all threat assessment experts agree with this concept, Meloy and O’Toole (2011) describe leakage as one of eight warning behaviours that aid threat assessment: Pathway warning behaviours . Behaviour is part of research, planning, preparation or implementation of an attack.

Fixation warning behaviours. Indicating pathological preoccupation with a person or cause.

Identification warning behaviour . Identification with militaria, warriors, previous attackers.

Novel aggression warning behaviour . Violence unrelated to attack behaviour, committed for the first time, as the perpetrator tests out their ability to do the violent act.

Energy burst warning behaviour . Increasing frequency or variety of activities related to the target.

Leakage warning behaviour . Communication to a third party (intentional or not) of intent to do harm to a target.

Directly communicated threat . Communication of a direct threat to the target or law enforcement.

Last resort warning behaviour. Increasing desperation or distress through declaration in word or deed. The majority of school shooters demonstrated leakage or disclosure of direct threats, either to third parties or directly to the target. These range from the subtle (innuendo, comment) to direct attempts to enlist help. Occasionally, leakage occurs to mental health professionals, as in Charles Whitman who killed 14 (University of Texas, 1966). He told a university psychiatrist that he fantasised about ‘going up the tower with a deer rifle and shooting people’, 5 months prior to doing exactly that. Leakage may arise from a desire to court respect or elicit encouragement from others, or while attempting to frighten or intimidate. However, it rarely arises out of a desire to be stopped; those planning such incidents seldom possess the empathy that such a move would entail.

Psychiatric perspectives The impact of these incidents reinforces the need for mental health practitioners to remain vigilant. Perpetrators may have been bullied or may suffer from panic attacks, social anxiety or depressive symptoms; some have reported suicidal ideation. Other studies have reported perpetrators previously being treated with counselling, benzodiazepines and selective serotonin reuptake inhibitors (SSRIs). Psychosis is less common. The perpetrators of school shootings expect to die, either by suicide or being shot, but this seems to be part of the cultural script rather than a primary goal. Child and adolescent psychiatrists, general psychiatrists, psychologists or school counsellors may find themselves in possession of information that could be decisive in averting a tragedy. This may arise through professional contact with the would-be perpetrator or via peers, parents or staff who have been alerted to concern, directly or indirectly. While clinicians may feel that divulged threats are not uncommon and therefore tend to minimise such utterances, it is worth considering the potential impact and evaluating the feasibility of such threats. Collateral history can be informative. Practitioners should assess any potential threat on its merits and consider the credibility. Sometimes, distinctive warning behaviours are known to different people, each unaware of what others know. There may be a tendency to dismiss, rationalise or otherwise overlook these behaviours but like a jigsaw, sometimes the pieces together demonstrate a different picture. A report to the State Governor about Seung-Hui Cho revealed an extensive history of depression, selective mutism, and increasingly threatening behaviour. There were numerous warning incidents but ‘no one knew all the information and no one connected the dots’. There was a lack of communication between the various agencies involved, due to misunderstanding of privacy regulations. The report concluded that there was in fact ample leeway to share information in potentially dangerous situations. For psychiatrists sharing information, this entails a judgement regarding the duty of confidentiality versus duty to warn. In some US states, this is addressed by the Tarasoff judgement, after a patient told his psychiatrist of his intent to kill Tatiana Tarasoff, before doing so. While this judgement does not apply to Australia and New Zealand, the Royal Australian and New Zealand College of Psychiatrists Code of Ethics (2010) states, A breach of confidentiality may be justified on rare occasions in order to promote the best interests and safety of the patient or of other people. Psychiatrists may have a duty to inform the intended victim/s and/or relevant authorities. Many Australian and New Zealand jurisdictions do have protocols for sharing information, in order to prevent acts of violence. Practitioners would be strongly advised to discuss with managers and/or defence organisations prior to any breach of confidentiality, where time permits. For forensic psychiatrists, a specific threat assessment may be requested. Consideration of collateral history is vital. A structured professional judgement approach is recommended, for example, using the Structured Assessment of Violence Risk in Youth (SAVRY) or, for adults, the HCR-20 version 3, to adopt a thorough and evidence-based approach and ensure defensibility. Structured professional judgement is widely used in threat assessment and has been found to be reliable and valid. It allows assessment of correlates of risk, leading to consideration of risk scenarios and assessment of likelihood, severity, imminence and nature of an incident. It lends itself to implementation of management strategies through monitoring, supervision, treatment and enhancing victim safety.

School characteristics and responsibilities While most research has focussed on perpetrators, there is evidence that school characteristics are relevant. A school environment which permits anonymity or isolation, or contributes to students feeling disenfranchised and marginalised may interact with students’ personal characteristics leading to fertile ground for violence. Obvious vandalism, chaotic classes and hallways, strong cliques and staff behaviour (scolding pupils in public, ignoring bullying) are associated with student violence. Staff who are poorly invested in pupil welfare or ignore bullying may fail to identify or act upon early warning signs. Some jurisdictions have developed strategies to detect leakage and prevent nascent school shootings. Colorado’s Safe2Tell® reporting system allows phone and web reporting. Some schools have developed emergency plans to manage violent incidents, and larger institutions are developing capacity to manage threatening behaviour on campus.

Conclusion School shootings are rare, profoundly distressing events which impact individuals, the wider community, health services and local and national policy. Like mass shootings generally, they defy simplistic explanations. Psychiatrists and other health professionals have a role to play in threat assessment, identification of and reaction to leakage or other warning behaviours, subsequent evaluation of offenders, support for survivors and developing policy.

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship and/or publication of this article. Funding

The author(s) received no financial support for the research, authorship and/or publication of this article