Four chief constables - Surrey, Staffordshire, Leicester and West Midlands - are openly defying the prissy “performance targets” that have been poisoning police work. They fold their arms, plant their boots foursquare and refuse to play. With luck, more will have joined them by the time you read this. Chris Sims, of the Staffordshire force - hitherto high-scoring - robustly says: “I expect to drop down the league tables because I am no longer chasing every one of the dozens of performance measurements.” He will put public demands before those of Whitehall statisticians. Good. About time too.

The requirement to log as many “sanctions” as possible has skewed policing towards a rush for fast, easy results and away from the more time-consuming crimes people care about: burglary, mugging and vandalism. Even if commanders

were not swayed by their performance-related pay bonuses hingeing on getting the figures right for the Government, the desire to rise up a league table is (as equally skewed school managers know) almost irresistible. They do well to resist it.

The problem is not new. It has been grumbled about for years by the public, picked up by many of us commentators, brilliantly satirised in Private Eye's “Police Log”, and chewed over in last week's Civitas investigation into the alienation from the police of the law-abiding public. High police achievement, as measured by Whitehall, simply does not relate to public perception. It is a prime example of how much damage government can do when it micromanages by target, blindly, from the top. Arresting or cautioning a basically harmless person for a trivial offence is easier and quicker than solving worse crimes, but ticks a box all the same.

Motoring offences are often cited (though it is hard to feel sympathy for arrogant Clarksonians who whine about speeding tickets or the Breathalyser) but there are more valid examples. School playground fights have been primly logged under the Public Order Act, a child arrested for chalking on the pavement, a 19-year-old held for five hours after holding the door open in an Underground lift. Last year a girl of 14 was charged with “common assault of a sexual nature” for jokingly pinging the bra strap of a classmate: it took seven months for the case to be thrown out.

Last month a boy of similar age was reported under the Public Order Act for holding a placard saying Scientology is a cult. One senior policeman (just retired) tells me of a neat little trick carried out by young officers called to domestic or neighbour disputes. “Instead of calming them down, which we always used to do,” he said, “you provoke them on purpose until one of them lashes out or verbally abuses you. Then you arrest him. Crime, detection, clear-up - all in a few minutes. Tick the box, magic.”

But as the four chief constables bravely raise two fingers to government and pledge “commonsense policing”, a new hurdle appears ahead. Together with a general but unfocused desire for “commonsense” goes an almost equally general approval of “zero tolerance”, the US theory that says that you can bring down crime by stamping hard on all disorder - broken windows, graffiti, litter, public drunkennness. The crime figures for New York, and some targeted British cities in the 90s, seem to show that it works.

To see it taken to extremes, go to Singapore where the draconian strictness of policing means that one discarded paper cup or blob of chewing-gum means you end up litter-picking all day in a luminous tabard with “Corrective Work Order” stamped on the back. Even if you're a managing director. Singapore is not an ideal regime - you can't demonstrate proper dissent there either - but it must be admitted that a girl can walk around the city confidently even at 3am, and that smiling queues form for the subway. Here, the filth and aggression of many urban settings bring on real fear, and widespread yearning for the zero-tol philosophy. When even the cute idea of a “last cocktail party” before the drink ban on the London Underground ends in violence, vandalism and vomit, the yearning becomes intense.

But you see the problem? How do you combine “commonsense policing” with “zero tolerance”? Especially in a chippy, class-conscious society where hostility rises all too readily between the margins and the middle class? One officer's commonsense might blend with class chippiness and tell him (or her) to pounce on a glossy 4x4 as it pauses on a double yellow to drop off a well-scrubbed child at Cubs (and search that smug kid! He's got a penknife!). Cue middle-class outrage. In another part of the urban forest a cop with different social instincts decides to stop and search a hooded black boy strutting with attitude and shouting to his friends, only to meet with equal outrage because it makes him late for his gospel singing rehearsal.

As a ludicrously harmless middle-aged mother I was miffed when a rookie policewoman gave me three points and a lecture for stopping with one wheel on the zig-zag lines in an empty small town late on a wet Christmas Eve, while my son quickly used a cash machine, and the usual drug deals proceeded serenely unmolested in the nearby pub. That was not commonsense policing; on the other hand, it definitely was zero tolerance. So if I want the knife kids searched and the drunks and dealers zapped, logic says I must accept it.

The defects of British policing result, I suppose, from two things. One is a lethal synthesis of target culture and zero-tolerance theory: easier to win points by nicking mild-mannered Clark Kents for dropping an apple core than to face down a burgling Superman. And the other is the increased distancing of police from local communities.

Popping in to school assemblies and putting up matey posters is not enough. The more genuinely close they are to the streets, the better cops will know the difference between someone - of any class - who is just having a bad day, and someone who really needs stopping. That knowledge alone can create trust, and lead to public co-operation in detecting serious crime.

Meanwhile we bra-pinging, apple-chucking, lift-stopping, placard-waving 33mph-driving desperados will just have to soldier on in the present atmosphere of vague nervous resentment and glum expectation that they'll get us for something in the end (but probably won't get our burglar). So salute the four chief constables for setting out on the right track. It's a stony path ahead.

Read Libby Purves in her new slot every Monday

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