THE best police forces in Britain are up to four times more likely to catch criminals than the worst. New “performance indicators” for area divisions show an alarming variation in detection rates.

The discrepancies are disclosed in internal Home Office computer figures prepared for all of the 250 divisions — now known as basic command units (BCUs) — in England and Wales. The statistics have been made available to police forces for the first time.

They compare the performance of different commanders down to superintendent level in arresting criminals for the year to October 31, 2004.

Critics of the system say the government is trying to adopt the “Compstat” (computer statistics) method launched 10 years ago under Rudolph Giuliani, then mayor of New York, and since adopted by many American cities. The strategy holds police commanders accountable for crime rates.

Most of the best-performing BCUs are in Wales. Criminologists put this down to settled communities where victim and offender may often live in the same neighbourhood.

The unit with the best detection rate for all crimes is the western area of north Wales with 47.37%. The worst performer on detection of all crimes is Bristol at 12.96%.

“We’re truly proud and don’t intend to let it slip backwards,” said Richard Brunstrom, chief constable of North Wales police who has been criticised for his enthusiasm for speed cameras.

The worst figures for specific crimes are in London. Lambeth in south London records only a 3.19% detection rate for vehicle crime, compared with Newport, Gwent, with 42.54%.

Police at Heathrow airport, helped by anti-terrorist measures, have the highest detection rate — 83.33% — for robbery.The worst unit, with a detection rate of 8.22%, is Brent, northwest London.

Ealing in west London has the lowest detection rate for burglary at 6.08%. The highest is Newport with 51.95%. Stephen Pound, Labour MP for Ealing North, described Radio 4’s Today listeners as “bastards” last Christmas for voting for a move to allow householders to shoot burglars as their favourite subject for his private member’s bill.

Scotland Yard refused to comment on what it said were unpublished figures. But police commanders in Maidstone (population 138,000) in Kent have an uphill battle to explain why their counterparts in Newport (population 137,000) do so much better.

The burglary detection rate is 6.68% in the Kent town, but 51.95% in the Welsh city.

The national average is 13%.

Newport has more frontline officers: 297 compared with 268 in Maidstone. But at 15 burglaries a year for every 1,000 homes, compared with fewer than seven in Maidstone, it has a higher crime rate. Yet it has managed to reduce burglaries by 20% in the past year.

Detective Chief Inspector Mark Sutton, head of Newport CID, said: “It’s down to solid police work. We proactively investigate every offence of burglary. Victims will always have the attendance of a police officer when it is reported. We then give a full service via the scene of crimes officers and investigators.”

Kent’s reaction to the emergence of the figures has been swift and effective. In the past four weeks, 419 burglary suspects have been arrested in a county-wide sweep codenamed Operation Castle. A Maidstone police spokesman said: “Over the past 10 years we have reduced burglary by about 70%. When the burglary rate is so low, you are less likely to arrest a high number of people in relation to those that do occur.”

Yesterday a gang drove a mechanical digger into the town’s Halifax bank and stole its two Cashpoint machines.

Barrie Irving, director of the Police Foundation, an independent think tank, said that “environmental” differences between two areas of similar size should count for a variant of 60% to 70% in comparative figures, not the 850% difference in detection rates between Newport and Maidstone.

Strict Home Office rules prevent police forces from “massaging” the figures by getting convicted criminals to confess to other offences.

Irving added: “The Home Office is using these figures to make people sit up and take notice. If it provokes managers on the ground to think what their neighbours are doing, it is having the same sort of effect as the American system.”

Peter Waddington, professor of political sociology at the University of Reading, said that half of all break-ins were committed by a 3,000-strong burglar community, many of whom were drug offenders.

“They rob, they score drugs. It is easier to pick them out in a settled community in Wales than in London,” he said.

The best and worst detectives, www.sunday-times.co.uk

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