Over breakfast last week a senior police officer reeled off impressive crime figures for his patch. All crime was down by 20 per cent, the number of violent offences had fallen by 10 per cent and vehicle crimes had been halved.

Then he paused, dropped the political mask that so many chiefs have to wear, and admitted that none of these numbers gave him any reassurance. “The problem is that the crimes that really worry people, and me – the teenagers running around with knives and guns – seem to be getting worse” This is the story of policing in the past few years: a maddening obsession with measuring performance. Police chiefs have been walking around with leaflets in their pockets depicting their performance in graphic form or with their latest crime stats imprinted on their minds. The public stopped believing such figures a long time ago.

Sir Ian Blair, the outgoing Met Police Commissioner, conceded as much a few months ago. “In London,” he said, “there is almost no public faith in the crime figures.” This can be explained partly by the surge in teenage murders in London, which no amount of downward lines on graphs can disguise. Recent requests under the Freedom of Information Act have revealed that the official figures on gun and knife crime are gathered in a way that is misleading.

Today’s disclosure that forces have been wrongly collating numbers on violent crime hardly comes as a surprise. The numbers game is wide open to interference, manipulation, omission and outright trickery. If the politicians get their way and subject police forces to more local political control, there is a real possibility that pressure to “juke the stats” will intensify.

Policing is about protecting the public, not producing tables and graphs that keep only Whitehall and local councils happy.

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