Comment: dealing with knife crime is an urgent task

Carrying a knife "for protection" has become a kind of arms race in which young people believe that because others have blades, they must carry one too. But going out armed vastly increases the risk that a minor confrontation over a dirty look or gesture of "disrespect" will turn into a fatal incident.

The current trial for murder of those involved in the death of 14-year-old Martin Dinnegan, killed for a dirty look, and the recent fatal stabbing of Harry Potter actor Robert Knox, demonstrate how the carrying of knives spreads violence beyond gangs to a point where any law-abiding young person on London's streets and public transport could be at risk.

As a senior member of the judiciary, Sir Igor Judge, put it last week: "Every weapon on the streets is a public danger." Now we need to look for solutions to a deep-seated problem.

The Metropolitan Police's leaflet and online campaign this week, using shocking images, is a good start. So was the statement by Met Commissioner Sir Ian Blair that parents need to confront children over the carrying of knives. If resources are indeed limited, as he has claimed in the past, there is a strong case for additional funding.

The Mayor must also make good on his commitment to increase police numbers on public transport, along with his promise to withdraw free bus travel from offenders.

Our charter calls for the use of targeted stop and search powers by police to be stepped up, because it is already showing results and is increasingly backed by all sections of the community. Search arches and scanners must be used at more Tube and rail stations. The authorities should consider extending their use in and around schools and sports centres. The police presence at priority schools and pupil referral units should be maintained.

We also want to see children taught in school that respect cannot be won at the point of a knife - and for those in the media who create films, computer games and rap lyrics to remember that their glamorisation of violence can shape real-life behaviour.

And when the knife carriers are caught, they must be properly dealt with by the courts. The Met and the Crown Prosecution Service have promised to stop letting so many off with cautions, but the more robust charging policy must be delivered with consistency. Where witnesses need protection in order for charges to be brought, that must be provided.

The courts must also recognise their role. In 2006, less than a fifth of those convicted of going out armed with a blade went to prison. The courts may not wish to imprison young people but absolute and conditional discharges simply send a message that it is easy to get away with carrying a knife, and do nothing to reverse a trend which is spiralling out of control. Those who do go to prison must be shown the impact of their crimes on victims and how to manage their anger in future.

It may be too late for Martin, Robert and all the other young victims, but it is not too late for the Mayor, the Met, schools, parents and youth charities to come up with solutions. Fifteen teenagers have already died violently in London so far this year, 11 of them from stabbings. This is an urgent task.