Two London MPs are calling for all under 18 year olds found in possession of a knife to be imprisoned.

There is a real problem with knife crime in poor urban areas like Enfield. Recently two rival gangs fought with machetes, knives and guns there and a sixteen year old was stabbed in the hand. These are terrible incidents which traumatise the community as well as those actually involved. But I don't agree that the answer is to lock them up. David Burrowes and Nick de Bois want all those found in possession of a knife to get a mandatory sentence of imprisonment. It is proposed in the Legal Aid, Sentencing and Punishment of Offenders Bill that all adults found with knives should be locked up, but children are excluded. David Burrowes and Nick de Bois want children and teenagers to get the same punishment as adults. But their plea is based on flawed logic - that imprisonment of knife carriers will create a safer society.

Thousands of children and teenagers have already been imprisoned for carrying knives, but this has not acted as a deterrent. Of the under 18 year olds who are imprisoned, over 70% are reconvicted within a year. Of those who are released, many are back in prison within six months. Prison does not act as a deterrent. The individuals who are imprisoned keep on committing crimes and their friends carry on carrying and sometimes using knives. The only answer to knife crime is to make teenagers feel safer and get them to understand the harm knives cause.

Teenagers carry knives because it makes them feel safer. They feel they need a strong means of protecting themselves from their peers who carry knives. We need to break this vicious circle - to persuade teenagers that there is a greater risk in carrying a knife than not. Part of the answer is to get teenagers to understand the damage knives can do, both physical and psychological. We need more prevention programmes where nurses prove how lethal knives are, and more restorative justice. There is no more powerful way of changing behaviour than to get someone to face their victim and their victim's family, to hear the devastation a thin blade caused and to make amends for the hurt done. Restorative justice is not a fail-safe, but I have come across nothing else that has the same power to turn someone away from crime. In Northern Ireland teenagers who carry knives have to face their potential victims, say sorry and make a plan of how to make up for the harm they've caused. Teenagers in North Ireland still re-offend, but on average they re-offend less often than their counterparts in England and Wales. We are all agreed on the need to stop teenagers habitually carrying knives but imprisonment is a blunt, and ineffective, instrument.

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