Violent crime figures are the least reliable, the report says

Just 17 of the 43 forces have reached standards set by the Home Office, with four giving serious cause for concern.

As a result crime fighting efforts may not be concentrated in the right place, the public spending watchdog said.

Home Office minister Hazel Blears praised the "considerable efforts" made to meet standards but said "further work was needed".

But shadow home secretary David Davis said the findings suggested crime levels could be higher than reported.

The report found the majority of forces still had "some way to go" in recording crime.

Red ratings

The Metropolitan Police service was among four forces given a red rating in the commission's "traffic light" system, slipping from amber last year.

Cleveland, Cumbria and South Yorkshire were also given red ratings.

If forces don't record crime accurately they don't know how to respond BBC correspondent Neil Bennett

Seventeen authorities met the set national standard and were rated green - compared to 12 in 2003.

Twenty-two authorities were rated amber, compared to 21 in 2003.

BBC correspondent Neil Bennett said police were getting better in the way they recorded crimes, but that if forces did not record it accurately they would not know how to respond.

For instance, many had strategies for helping women who were victims of domestic violence, he said.

But if original 999 calls were not being logged properly there may not be the right intervention, creating a real risk to those involved.

Slipped category

Despite the failings in police record keeping, the Audit Commission said the official crime figures did give a broadly accurate picture.

But it said the figures on violent crime, which jumped 11% in the second quarter of the year, were the least reliable.

In total, three forces - the Met, Cumbria and Gloucestershire - slipped down a category in the traffic light system.

A further eight had shown deterioration but it had not been bad enough for them to be reclassified.

The National Crime Recording Standard (NCRS), which forces are meant to implement, was introduced by the Home Office in April 2002.

Work needed

Ms Blears said the police service had achieved "very high standards in recording target crimes".

But, she added: "Further work is needed and the Police Standards Unit will continue to engage with the service to ensure forces record all information in the clearest and most efficient way."

Association of Chief Police Officers (ACPO) spokesman and Northamptonshire chief constable Peter Maddison agreed forces had work to do, especially for those with a red rating.

But he added: "The fact most forces are rated green and amber is a huge improvement on what we had prior to NCRS.

"The police service now needs to build on these achievements."

Shadow home secretary David Davis said: "It is essential for crime statistics to be recorded accurately.