Knife crime is a teenage craze - and it will pass

It's interesting that the police should describe a tactic with a success rate of 4.2 per cent as something which enables knife-carriers to be "caught" and "dealt with". The Youth Justice Board estimates that up to a third of teenagers (that is, 150,000 in London) occasionally carry a knife; at least 25,000 London kids are reckoned to carry one regularly. Even if last weekend's effort is maintained, which seems unlikely, it will take a long time to catch them all.

As knife crime consumes ever more newsprint, you can understand why the politicians have reached for those trusty potions "more policing" and "stiffer sentencing". They have to make some sort of response to public concern. That's the easiest one to make. And with six people stabbed to death last week alone, public concern bordering on panic is taking hold.

Some of it is, frankly, absurd. One Sunday newspaper reports that teachers, railway workers and staff in those well-known dens of violence the Royal Parks are being issued with, or investigating using, body armour. Just out of interest, I checked how many London teachers, railway workers and park-keepers were stabbed on duty last year: the answer is none.

Another Sunday paper claimed there were 14,000 instances of knife violence in Britain last year. The actual figure is half that.

This is not going to be one of those articles saying that the media have exaggerated everything, and it's all fine, really. Of course it isn't. True, the overall number of knife murders (around 260 a year nationally) has barely changed since 2000. True, the number of stab victims treated at London hospitals last year (731) is actually eight per cent down on the year before, and less than in each of the past four years. But non-fatal attacks are getting more serious; and there is, as everyone knows, a growing and frightening problem with knives and kids, most obvious in the record 19 child murders so far this year, 14 of them stabbings.

Yet it is precisely for that reason - that this is a problem with children - that policing is not quite the answer. Some will argue that even if stop-andsearch operations don't catch many knife-carriers, they are at least a deterrent. But the evidence suggests that youngsters are not, so far, deterred.

Under the Violent Crime Reduction Act 2006, the maximum sentence for possession of a knife was doubled, to four years. There has been more police action, and more children have been locked up. But since 2006, there has also been a lot more child knife use. The vast majority of kids who seriously wound or kill other kids are caught and punished. It hasn't made the slightest difference to the rise in child knife violence.

Thinking in terms of policing, sentencing and deterrence assumes that teenagers respond to the same kind of threats and stimuli as adults. That's not always the case. Adolescents are often less rational. How many teens always think through the likely consequences of their actions?

Nor, in the short term, is the other oftmentioned response to youth knife crime - tackling the "root causes" - going to help much. Of course, attacking social and family breakdown, and addressing educational failure, is very necessary, and also right in itself. But that will take years, far longer than the public wants to wait. So what do we do in the meantime?

One fascinating thing about England's youth knife "epidemic" is that it is largely confined to London. Other big cities, like Manchester and Liverpool, have seen nothing like the same rises in knife attacks. And as knife-use by kids has risen in London, gun use has dropped.

Yet the young people of Manchester and Liverpool face pretty much the same social problems and family breakdown as ours do. So maybe those "root causes" aren't the main causes of London's problem at all. Nor can it be the criminal justice system or changes in sentencing that account for most of the difference - that, too, is the same in Manchester, Liverpool or London.

There must be some specifically London factor which explains why our kids have (to some extent) put down guns and (to a much greater extent) taken up knives.

Teenagers may not respond to the same stimuli as adults but they do respond to different ones. I can't help wondering whether the explosion of London child knife use is as much due to local fashion as anything else - a perverted teenage copycat craze, with particular weapons going in and out of fashion like particular trainers.

And I can't help wondering whether the current media and political angst is actually fuelling that craze. Does all the coverage of knife crime reinforce kids' idea that London is a place where going unarmed is risky? Do the TV pictures of those flowers at the murder scenes, those messages to "fallen soldiers", add a touch of glamour to the wretched business of dying young?

If I'm right about knife use being partly a fashion, the great thing about fashions is that they change. This problem could actually get better of its own accord, a bit like the crack cocaine epidemic did in America. We must try to think of ways to hurry that process along.

I'm not saying the press should stop reporting knife crime but I think we should describe the "epidemic" more precisely. And the political response should aim to be a fairly low-key, behind- the- scenes sort of one. Anguished summits and flak-jackets for park-keepers might actually have the opposite effect to that which we intend. In knife crime, there may be a contrast between the tactics needed to reassure the public and those needed actually to tackle the problem.