The police arresting 200 people will have less effect than their preventative and community work. But it spins so much better

PR stunts in the good old days used to be so much simpler. Back in 2007-08, when gangs hysteria was at its height, it was a simple narrative to sell. The classic police line was that a "Mr Big" had been caught ? the head of the hydra had been cut off, so the rest would fall away. Occasionally there would be the occasional announcement of a "gang summit" ? the police would say that they had gathered together the leaders of the gangs to call a truce, thus stopping the violence.

It was always so much bluster. Street gangs are, for the most part, little more organised than a riot. There are some extremely organised criminals involved ? but that doesn't mean that the police are dealing with Don Corleone-style organised crime. And the public have, thanks to a growing maturity in media coverage of the issue, begun to reject the political line that this is purely a law and order matter. The coalition has stuck rigidly to a line of carrot and stick being the way forward (with Bill Bratton the perfect poster boy) ? and now the police are doing the same.

So on Wednesday we saw more than 200 people arrested during raids across London ? the stick ? but at the same time we heard all about the other side of this raid. The Metropolitan police commissioner, Bernard Hogan-Howe, says of the Trident gang crime command that: "This is a step change in how we tackle gang crime in London. It will allow us to identify and relentlessly pursue the most harmful gangs and gang members. It will help us identify young people on the periphery of gangs and work with partners to divert them away."

The stick stuff is all a bit silly of course. Anyone with a passing interest in crime could have found out online there were raids coming at least two days in advance. Even the Sunday Politics Show let slip that there would be a "big gangs announcement" coming. You have to ask exactly who the young people were that the police arrested. A thousand officers produced one gun from the houses they raided. One suspects the number of charges pressed will be significantly lower than the number of those arrested, but that information will be kept somewhat quieter.

It's the carrot that's rather more interesting. Hogan-Howe told the BBC: "Although we are now nearly doubling the number of officers dedicated to tackling gang crime, the police cannot do this alone. It is vital we work with the public, local authorities, charities and other agencies to prevent young people from joining gangs in the first place." This is the kind of thing that people like me have been demanding for years. The police are only a small part of the picture when it comes to dealing with gangs. In fact, they're the agency that gets involved when it all goes wrong.

All the research shows that there's no one reason for someone to turn criminal. In 2007 I was asked to write a book about gangs. I didn't have much room for the mother with a black eye spitting in the face of a social worker; the father telling his son not to snitch. There are all sorts of factors: peer pressure, school exclusion, domestic violence, drug addiction, mental health issues, the simple fact that you're a naughty boy, often a combination of all the above. It means that if you really want to tackle gangs there has to be involvement at the earliest stages of a child's life. It's therefore the responsibility of everyone with whom a child comes into contact ? teachers, social workers, housing associations, doctors, voluntary associations, youth offending teams and others. So of course what Hogan-Howe's saying makes sense.

What the police have realised is that, of all these bodies, they're often the one with the best initial insight. So we're seeing a stark rise in preventative work: stopping bad stuff happening before it can have a chance to happen. We saw it at the start of this month in Enfield, when a bunch of young gang members were hauled into a court, shown pictures of stabbing victims, and spoken to by ex-gang members and a bereaved mother. It's good positive stuff, but it doesn't help your arrest figures ? and this is why there's a perennial problem with how we quantify the police's success, and it's also why the officers involved should be commended.

Community partnerships are nothing new, of course. How do we know that this "step change" is exactly that? There was, of course, huge concern over the fact that Operation Trident had been given the lead on gangs since its reputation took a battering over Mark Duggan. But quietly, this section of the force has built a number of strong partnerships with various community stakeholders. That said, I know of far less successful relationships too ? youth workers who've felt bullied into providing intelligence, who frankly wouldn't trust the officers as far as they can throw them. But Hogan-Howe didn't want Trident's work over the last few years to go to waste. Putting Trident at the heart of the gangs strategy is a bold move, to say the least.

The problem is ? there's no easy way to quantify it. Crime figures will never tell the whole story. All we can go on, really, is anecdotal evidence from our own neighbourhoods. In this vacuum of reliable data, you can expect no let-up in the kind of spin we saw today.

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