We don't need a new law on tackling intruders

The worst mistake would be to do anything which encouraged ordinary citizens to own guns

Let us stop and think a little before the momentum becomes overwhelming. A change in the law applying to householders who strike or even kill an intruder in their homes is becoming increasingly likely. A Conservative Member of Parliament, Patrick Mercer, having drawn first place in the ballot for private members' Bills, has said that he intends to put forward proposals shortly. They would offer complete freedom from prosecution to anybody in his or her own home who takes any action against an intruder so long as it is not "grossly disproportionate".

Let us stop and think a little before the momentum becomes overwhelming. A change in the law applying to householders who strike or even kill an intruder in their homes is becoming increasingly likely. A Conservative Member of Parliament, Patrick Mercer, having drawn first place in the ballot for private members' Bills, has said that he intends to put forward proposals shortly. They would offer complete freedom from prosecution to anybody in his or her own home who takes any action against an intruder so long as it is not "grossly disproportionate".

Mr Mercer would get the full backing of his own party which had, in any case, been working on a revised policy. Labour would be unlikely to use its majority to block Mr Mercer's initiative when a general election is only months away. Reform, therefore, is coming.

Under the law as it presently is, householders are allowed to use reasonable force when confronting an intruder. Why is this thought to be an insufficient criterion? I was once a member of a jury that considered a case which turned on the use of this same "reasonable force". A young man in a nightclub believed that he was about to be thumped by a fellow patron. He struck first. The police were called. He was arrested and in due course he was charged with assault.

After the evidence had been heard, the judge told us we had to decide whether the young man's action had been proportionate in the circumstances. The defendant knew that his potential assailant bore a grudge against him. He saw that he had raised his fist as if to strike. But, of course, his adversary may have intended only to frighten him.

Sitting in a central London court, we jury members, young and old, with different backgrounds, were typical of a cosmopolitan city. For almost two hours we debated the difficult issue of what constituted a proportionate response. Everybody spoke. Some jury members visibly changed their minds as the discussion wound on. We decided to acquit. I went away reflecting that I'd had seen our legal system working well. That is why I am not easily persuaded that the law needs changing in the case of a householder facing a burglar, a much simpler affair to assess than my jury case.

It shouldn't be changed because of Tony Martin, a Norfolk farmer, who was jailed for shooting dead a 16-year-old burglar, Fred Barass, in 1999. The intruder was running away when he was killed. Even David Davis, the Conservative spokesman on crime and punishment, says that the proposals he is working up would have been "unlikely" to have had any effect in that case.

Sir John Stevens, the outgoing Metropolitan Police Commissioner, argues that the law is too imprecise at the moment for people when they are in extremis. You should be absolutely clear what your legal rights are to defend yourself. "I am not talking about guns but people being allowed to ... use whatever is necessary ... against someone who may be armed with a knife," Sir John said in a recent interview.

He is right in the sense that people have got it into their heads that they will inevitably be charged and found guilty of assault or murder if they strike first. And if householders are confused about their rights, then they may fatally hesitate when they should act promptly to save their property or their lives.

But notice that Sir John said that he was not talking about guns. He will have had in mind the US where they manage these things very differently. Householders have an unqualified right of self-defence. In Oklahoma they may use any force, including the deadly variety. The result is that whereas in the US only 12 per cent of burglaries take place while the owners are at home, in this country the figure is more than 50 per cent.

But here is my second area of doubt. It is that a relaxation of the law will encourage British householders to acquire guns for self-defence. And that in turn would mean that we would have begun to imitate one of the worst features of the American way of life - which I otherwise greatly admire - its gun culture and all that goes with it. On an average day the US has one person in jail for every 120 of its population, which is five to 12 times higher than any other Western nation. No thanks.

Let us accept that Sir John is right. There is confusion - though I would be surprised to find that the "reasonable force" test isn't working well in practice. Nonetheless the standard way of clarifying a misunderstood area of the law is for the Lord Chief Justice to make a statement that reminds people of what the law actually is. Lord Woolf could issue what is known as a practice direction. In 2002, for instance, the question of mandatory life sentences was handled in this way.

Failing this, however, the wording of the relevant law should be tightened up but not going so far as the version likely to be proposed in Mr Mercer's Bill. The worst mistake would be to do anything which encouraged ordinary citizens to own guns. Then clumsy legislation would have made matters worse.