Mental health and aggression


Certain mental health conditions can lead to aggressive or violent behaviour in students. In the third of her series on mental health in schools, Dr Stephanie Thornton offers her advice.


Aggressive pupils are a major issue. Research last term from the Association of Teachers and Lecturers (involving 1,560 of its members) reported that half the teachers surveyed had suffered verbal abuse, including threats and intimidation, in the past year. A quarter of them had been physically assaulted.

This is unacceptable. Solutions generally propose better classroom management, a change in school culture (and so forth), or a new “super-head” – and sometimes such changes do have some effect. 

But the implication that classroom violence is simply a reflection of failures in school management is absurd. 

The evidence points to changes in society at large as the main culprit. Respect for teachers (and other professionals) has collapsed across the board. Where bad behaviour was once a source of shame, it is now more acceptable, if not encouraged in some contexts. 

Standards of parenting have declined: far more youngsters come to school without having learned either self-control or appropriate boundaries. And some families validate abusive behaviour: a quarter of teachers in the survey reported aggression from parents.

There are limits to the extent to which schools can counter the effect of such social changes – particularly given that the aggressive tend to be those pupils who have a poor commitment to school, who truant and “hang out” with groups of delinquents, gaining status with these peers by engaging in delinquency and disrespecting authority.

But in a tragic way, the aggression and even violence of such individuals is “normal”: a reflection of life situations and experience rather than mental disorder. As much as we might regret their behaviour, we can understand why, in their position, they might react in that way. 

But what when violence and aggression are driven by mental disorder? The possibility frightens us: violence of this kind can seem so irrational, alien and unpredictable. 

Take the murder of teacher Ann Maguire in April 2014, stabbed in her classroom by 15-year-old pupil Will Cornick. Cornick brought a knife into school one day, calmly got up and stabbed his teacher in the back. Then he sat down again, chillingly proud of his actions. 

This crime seems incomprehensible in a way that the murder of headteacher Philip Lawrence, stabbed while trying to stop a gang attacking a pupil, is not. 

We can perhaps understand that a man may be stabbed in the heat of such a fight. But not why a boy would coldly stab a popular teacher, apparently apropos nothing: that smacks of the insane.

How common is violence driven by mental disorder? Thankfully, it is rare. Despite popular stereotypes, the mentally ill are not particularly prone to violence, though it does sometimes happen, driven perhaps by paranoid fear or hallucination. Early treatment reduces the risk, so early recognition that there is a problem is vital.

Watch for signs that an individual may be “losing it”: losing control over frustrations or anxiety, for example, may be a precursor to a violent lashing out. 

More serious is the situation where there are indications that an individual may be losing contact with reality: paranoid ideas, delusional thinking, strange beliefs or behaviour should always raise suspicion of major mental illness. 

For most sufferers of such illness, the problem is primarily personal, involving a painful fear. But for a few, paranoid or delusional thinking fosters violence. Either way, getting expert help as soon as possible is vital.

What to do, should you be unfortunate enough to experience aggression that you suspect is driven by mental illness? Of course, the first priority in any such situation is safety: for the other pupils, for yourself, and for the disturbed individual. It is a judgement call in each situation as to what response that requires. 

Beyond that, expert advice in the face of such aggression is to react as calmly as possible. Avoid confrontation: it is likely to make aggression fuelled by irrational fear or by delusional thinking worse. A firm word, calmly spoken, can sometimes turn things around: “please stop” or “you are quite safe” perhaps may help the individual to regain control. Once the incident is over, get expert help immediately.

Often, the more severe mental disorder becomes, the more transparent it is that there is a serious problem, as the sufferer progressively loses contact with reality. Not so with one potentially dangerous mental disorder. 

Cornick was not diagnosed as mentally ill. Rather, he was diagnosed as suffering from a personality disorder (antisocial personality disorder or APD, popularly described as psychopathic personality). 

His fantasies of killing his teacher, his chilling pride in succeeding, his utter lack of compassion, conscience or remorse are classic characteristics of APD. Such individuals do not fall out of step with reality in the way those with major mental disorders tend to do, and so can be hard to spot. Not for nothing is psychopathic personality described as “the mask of sanity”.

Psychopathic murders such as that of Ann Maguire are extremely rare. But APD itself is far more common than you may think: up to five per cent of the population inherit some element of this personality (boys out-numbering girls five to one), so you are likely to teach quite a number of such individuals through your career. Luckily, the vast majority of these will never commit any crime, let alone a violent crime (in fact, society needs them: their personality type allows them to fill vital roles, for example as surgeons and leaders untrammelled by the squeamishness or sentimentality that might prevent others from pushing the boundaries of medicine or taking tough decisions). And even among psychopaths who do kill, the vast majority only commit their first attack on a human being long after leaving school.

Can we identify the very few truly dangerous APD individuals who represent a real threat in our schools before they commit any crime? It is a massive challenge. Actually, we can identify APD in children as young as five years of age. But what our genetic, neurological and psychological tests cannot do is tell which of these will be safe citizens, and which are the rare individuals who will go on to commit terrible crimes.

Psychopathic attacks from Columbine to Cornick’s seem to come out of the blue. But this is not actually the case. Studies in the USA (where such crimes are more frequent) show that the perpetrators typically give off clues beforehand: they glorify others who have committed similar atrocities, and they leak their intentions to friends. 

That was certainly true of Cornick: he told his friends of his hatred for Ann Maguire and his fantasies of killing her months before the attack. He discussed these fantasies extensively on Facebook during Christmas 2013. He showed classmates the knife on the morning of the attack and boasted of his intentions. 

His peers found all of this very disturbing. But who can blame anyone, if no-one took it seriously enough? Knives are, sadly, not rare in our secondary schools, and nor is bloodthirsty boasting. Actual cold-blooded murder is unthinkably rare.

The only hope of identifying the truly dangerous such as Cornick is to change our mindset to think the unthinkable. Expert opinion is that we should take every murderous fantasy seriously, encouraging students to report such things as soon as they come to light.

Mostly, such fantasies will turn out to be no more than that: fantasies. But just occasionally they will be a warning of major mental illness or dangerous APD. Either way, murderous fantasies should not be accepted in our schools. 

Whether “just fantasists” or truly dangerous individuals, urgent expert assessment and intervention offers the possibility of re-orientation to a more pro-social life.

  • Dr Stephanie Thornton is a chartered psychologist and former lecturer in psychology and child development.

Mental health
In this on-going series, expert Dr Stephanie Thornton is tackling a range of mental health issues, offering practical advice to school staff and leaders. This is the third article. To see the articles as they publish and for all SecEd’s mental health advice and guidance content, visit
Photo: iStock



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