'Don't misuse crime figures'

London's police chief made a dramatic intervention in the mayoral campaign today - warning candidates not to "misinterpret" crime statistics to portray the city in a bad light.

As both Ken Livingstone and Tory candidate Steve Norris delivered major announcements on law and order, Met Commissioner Sir John Stevens made clear he would not tolerate any politician obscuring his own "message" that crime is under control.

In an email to Mr Norris, Mr Livingstone, Liberal Democrat Simon Hughes and other contenders for the June poll, Sir John seizes on fresh statistics showing that London has the second lowest level of reported violent crime in England. He also hails new figures claiming that the capital is one of the safest places in Britain. The memo - leaked to the Evening Standard - reveals that the latest British Crime Survey, a region-by-region poll that includes offences unreported to police, has found that only the South-West is safer.

Sent by Brian Paddick, the Met's Deputy Assistant Commissioner, it warns: "Sir John Stevens is concerned that violent crime statistics are not misinterpreted by mayoral candidates." The email states that annual crime figures will be released publicly next week "and it is important that the Met delivers clear messages when this happens". "[This] briefing is intended solely for mayoral candidates ... we would prefer that the briefing itself should not be copied to the media," it adds.

Sir John's remarks were sure to be pounced on by Mr Norris's opponents as he launched his anticrime campaign with a series of posters and press ads claiming that violent crime has soared by 20 per cent under Mr Livingstone.

The email briefing to candidates concedes that violent offences have increased by 19 per cent from 2000 to 2004, with the bulk of the increase coming from offensive

weapons and harassment. A total of 189,000 offences were reported for 2003-4, equivalent to one violent crime every three minutes.

But Sir John argues that the rise stems from a drive by police to encourage reporting of crime and by changes in compilation of statistics to include offences not previously labelled violent.

The police chief quotes more new figures showing-that so-called "major violence" such as murder, rape and grievous bodily harm has increased by only two per cent over four years.

The British Crime Survey shows London has just under 600 such crimes per 10,000 adults, compared with more than 10,000 in the South-East and 750 in the North-West and West Midlands.

"While increases in violent crime can appear worrying, the British Crime Survey shows the reality, that London has one of the lowest rates of violent crime," Sir John says.

However, Mr Norris could point to the Met's own figures indicating it has the worst violent crime rate in the UK. Sir John's own briefing shows that more than 300 such offences are committed per 10,000 of the population, well above other regions.

Mr Livingstone today claimed his own success on crime as the Transport Operational Command Unit, Britain's only dedicated unit for tackling crime on buses and relating to minicabs, opened a new HQ for south-west London.

The Mayor used the occasion to release figures showing record numbers of arrests of illegal minicab drivers.