A third of the records held by the Driver and Vehicle Licensing Agency (DVLA) are inaccurate, hampering police attempts to crack down on car crime, says the National Audit Office (NAO).

There are 950,000 vehicles on UK roads whose details registered with the DVLA are not up to date, according to the report published last week.

A survey in 2003 found that 90 per cent of records were good enough to help police trace the registered owner. But a year later, 32 per cent of records were found to contain an inaccuracy of some kind, the same proportion as 10 years previously.

'The DVLA should improve the accuracy of its vehicle and driver databases,' says the NAO report.'The Agency should explore the possibility of obtaining up-to-date names and addresses from the electoral register or private sector businesses so that it could write to drivers and vehicle keepers to update records.'

Lack of accurate records causes problems for police initiatives that rely on automatic number plate recognition systems or on DVLA verification of driver details.

However, the NAO found the continuous registration scheme launched by the DVLA in January last year has had some positive effect. Twenty per cent more motorists now notify the agency when they sell their vehicle, the report says.