I renounced violence when I was 11 because the boy who had started a fight with me hit me harder than I could hit him back. It took a little more time to acquire some theoretical underpinning for this practical aversion to physical force.

School helped. Watching 17-year-olds dangling petrified 11-year-olds from the second-floor stairwells, and then letting them drop into waiting arms, or seeing half a dozen boys waiting for rugby to end before beating up an unpopular fifth-former were a sharp education in the injustice of unrestrained aggression. Life was clearly safer with rules, procedures and fair punishments. Aggression was rarely an answer to anything. I grew up marching against bombs and wars and police violence, and told my children — who habitually ignored me — not to kick, punch or hit.

So I was taken aback by the surge of instinctive sympathy I felt last week when I heard about the case of Munir Hussain, a businessman jailed for a savage assault on a burglar who had threatened to kill him and his family. I should have felt Hussain’s behaviour was wrong, and in theory I did. In practice I, like hundreds of thousands of others who heard the story, was dismayed by his sentence.

What happened to the Hussain family in September last year was one of those random and frightening encounters that might hit any of us. Hussain and his two sons, aged 15 and 21, returned from prayers in the mosque to find three burglars on their property. His wife and daughter, aged 18, were already inside. All five were tied up, threatened with knives and told to lie on the floor or they would be killed, and Hussain was beaten.

One son escaped and ran to alert Hussain’s brother Tokeer, who lived in the same street. When Tokeer arrived, Munir threw a coffee table at the burglars, and the two brothers chased the gang down the road. They caught one man, Walid Salem, in a front garden. They hit him with a pole, a hockey stick and a cricket bat. The bat was used with such force that it broke in three places. Salem — a career criminal with 50 convictions — was left with a fractured skull and a brain injury.

The judge was clear about why he was passing a jail sentence of 30 months on Munir, and 39 months on his brother. If people were allowed to inflict their own instant and violent punishments on an offender, he said, the rule of law would collapse. We had to allow the criminal justice system to take its course.

Undoubtedly the judge was upholding important civilised values. But what he was describing, and what the legal system obliges him to assume, is the existence of a perfect world, in which citizens need not act because criminals are always caught and always sentenced, and in which terrified victims may never be excused for reacting in an adrenaline rush of anger and fear. The reason his judgment has caused widespread unease is because the rest of us are conscious of living in a darker and chaotic reality, where justice often doesn’t happen, and where people in a panic may react in an appalling but understandable way.

No member of the public assumes that the police will always be able to track down burglars and assailants. Official statistics show that they are right to think so. Less than a third of all crime reported to the police is cleared up, and for burglary the figure is less than a sixth. Even this is an understatement. Last week the Home Office announced that the police had been failing to investigate thousands of crimes, because officers had been allowed to define them as “no crime” without inquiring further. It is estimated that 200,000 offences a year, including serious assaults, have been wrongly ignored.

Whether because the police are badly managed, incompetent or simply faced with an impossible task in a complex society, they can’t guarantee anyone the satisfaction of seeing criminals in court. In the Hussain case, it was striking that although the judge was trying to uphold public faith in the legal system, the police had been unable to identify the other members of the burglars’ gang. The only man charged was the one who had been chased and caught.

The public know that the rule of law is patchy in practice. What they can also see, and the law can’t recognise, is the enormous psychological pressure that someone such as Hussain would have been under.

The existing law allows householders to use “reasonable force” against intruders. Hussain and his brother went beyond that. Yet it wasn’t as if they had launched an unprovoked attack on a defenceless teenage intruder. These burglars were armed and violent and had threatened to kill the family. Their victims were terrified. In that situation any human being could be pitched into a state where survival and security are all that matter.

Primitive instincts take over. When the burglars were confronted and ran, it seems unrealistic to have expected Hussain to stop and consider Home Office guidelines before giving chase. For all he knew, the gang were off to find reinforcements before returning to retaliate. As his lawyer said, this normally peaceable individual reacted “in the agony of the moment”, and “his calm judgment was not available”. While I could never condone his violence, I can understand how it might have happened.

This is not an argument for giving householders a right to attack intruders as they please. If burglars knew that any break-in might mean injury or death, some might be deterred, but others would come with guns or knives and be prepared to use them first. The more you raise the stakes, the more dangerous you make the game. One of the only virtues of British burglaries — and I’ve suffered several — is how unusual violence is. Burglars here want laptops and jewellery, not trouble.

What I am arguing is that the law should recognise what is essentially the provocation defence. It is not reasonable to demand that violent intruders who carry weapons and threaten to kill should always be met with a calm and socially responsible reaction. Actions such as Hussain’s have to be condemned by the legal system, because its function is to maintain social order, and the rest of us cannot and should not be encouraged to do what he did. But his inner turmoil should be recognised too. In this case, his guilt should be accepted, but his sentence should be suspended. Leaving it unchanged will just confirm many people’s belief that the criminal justice system simply is not fair.

Minette Marrin is away

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