There is a sex offender near you

Whatever he does for teenage totty, I just can't get aroused by Piers Merchant. The Mensa-certified brainbox should grasp that no 17-year- old without an ulterior motive would snog a bloke who wears style-free trousers with a belt that went out of fashion about five years before she was born. However, it's for the Beckenham Conservatives to work out who they want to offer to the electorate.

But the relish with which Westminster and its camp followers have devoured this story helps to explain why the electorate feels that the political class has its own minority agenda. If Mr Merchant - or any other MP - is looking for real voter passion, he could have found it in any community that has been told that a child sex offender has moved into their area. There he would encounter a level of genuine fury that makes sleaze and scandal seem irrelevant.

Two days ago, Lewisham Council in south-east London issued some five thousand letters to its residents warning them that a convicted paedophile with a 15-year record of assaults on children as young as six years old had moved into the area. The council was inundated with calls from anxious parents, and despite rumours that the man concerned had fled, it is unlikely that local children will be on the streets this Easter.

The trigger for their warning was an edition of LWT's The London Programme, which showed the man, Michael Pedley, daily loitering outside local schools. The programme team also uncovered a truly shocking statistic: the incidence of child sex offending is so high that no London household is, on average, more than two hundred yards from a convicted offender. The estimate is conservative, because the victim's shame and the offender's intimidation ("if you tell anyone, you'll be taken away from your mum and dad, and they won't be there to protect you any more") ensure that this crime is massively under-reported, and hugely difficult to prove.

We do know that three out of four convicted paedophiles reoffend. The experts say that no one yet has a convincing cure. The paedophiles themselves say that they cannot change. Indeed, many try to validate their deeds with a sickening mantra: "the word paedophile simply means `lover of children', so there is no way I would hurt a child ... Having talked in depth to many of these men, I for one am convinced that they do not - do not wish to - change. So the issue for communities all over the country is - what should we do with such men?

The government's response is feeble. It proposes a register of offenders, which would be held by the police. It would be up to the offender to ensure that their addresses were kept up to date. It is laughable to suppose that men who have successfully spent a lifetime hiding their loathsome deeds would cheerfully put themselves in the police's hands.

A group of remarkable Dagenham women have banded together under the name "People Power" and collected nearly 100,000 signatures for their campaign to give local communities the right to know if dangerous men live in their areas. They argue that the evidence from America has shown that the risk of vigilantism is low. In Washington State, though, some 11,000 offenders have been named under community notification schemes, fewer than 30 instances of vigilantism have been reported.

There are, however, three problems with community notification. First, it implies an unrealistic acceptance of a paedophile's presence in the community. Any community that knows that there is a child sex offender in the area will simply prevent their children from going anywhere unaccompanied. Since this will affect virtually every part of the country, we would end up with a nation of children under house arrest.

Second, any community that does opt for notification will simply end up chasing offenders to another area. And chase them we will. The London Programme's survey shows convincingly that 75 per cent of us are relatively untroubled by the prospect of victimisation. Unfair it may be, but when we weigh the rights of sex offenders against the rights of children, there is no question who wins.

The third problem is that community notification effectively offers the power to determine who lives where to local communities. But would anyone in their right mind offer this power to the people in Nicholas Budgen's Midland constituency who are clamouring for a halt to immigration? Or to student ghettoes that may regard the odd pensioner as a complaining nuisance?

The alternative is, of course, equally unpalatable to all good liberals. You can dress it up in a thousand ways - reviewable sentences, special regimes, and so on - but there is no place for namby-pamby optimism here. The risks are too great. To put it in the language of the community: when it comes to child sex offenders, the only answer is to lock them up and to throw away the key.

I was once briefed by a Foreign Office official who told me that when it came to trying to get agreement in the Commonwealth, the "niggers in the woodpile" were the Tanzanians. As I laid hands on him, he giggled, "Just an expression."

Before the critics of political correctness get on their high horses in defence of the judge who used the expression to "work like niggers" let's be clear: don't. It is not like being called "jock" or "taff", and it isn't "just an expression". And if you want proof I can introduce you to some very angry niggers who would make Braveheart look like Bambi. You've been warned.