DVLA databases only "40 per cent" accurate

The quality of information in the Driver and Vehicle Licensing Agency's (DVLA) databases is so poor that police taking part in a high-tech number plate scanning trial were forced to resort to manual visual checks on suspect vehicles.

The weaknesses in the accuracy of data in the DVLA's databases were flagged up in a report into a year-long trial by 23 police forces using automatic number plate recognition (ANPR) technology to check vehicles against various intelligence databases.

Home Secretary David Blunkett has just announced £15m of funding to extend the ANPR project nationwide after the 'Laser 2' trial led to 13,000 arrests and the seizure of £8m-worth of drugs and property.

During the trial, ANPR teams in police forces were able to use the automatic scanning technology in police vehicles and CCTV cameras to cross-reference vehicle registration plates against information held in the Police National Computer, local intelligence systems and DVLA tax disc and vehicle owner databases.

But a report into the trial, commissioned by the Home Office and carried out by PA Consulting, slams the accuracy of data held in the DVLA's databases.

The report says the quality of data actually got worse over the course of the trial, falling from 51 per cent to 40 per cent, and police officers were forced to resort to carrying out visual checks on vehicle tax discs rather than relying on the DVLA data because of "decreased confidence in using the DVLA databases as the primary means of stop".

"The DVLA databases in particular were shown to be poor. As yet, there are no Criminal Justice Extranet (CJX) facilities for the electronic transfer of updated information to forces on a daily basis and this is a further limitation on database accuracy," the report said. "Further, there is a lack of rigorous understanding as to the precise causes of data inaccuracies. As data is key to ANPR, we conclude that this represents a weakness that should be addressed."

Among recommendations to improve the use of ANPR are direct links from police forces to the new computerised MOT database, which is due to go live later this year, and motor insurance databases, which flag up vehicles without insurance.

It also calls for a national "vehicle intelligence data warehouse" to reduce reliance on locally produced and held information, which would also fit into the national intelligence sharing strategy put forward by the Bichard Inquiry into the Soham murder investigation.

"This data warehouse should also hold ANPR reads and hits, which are themselves a vital source of vehicle intelligence and should be accompanied by the development of data mining tools of a more sophisticated nature," the report said.

Overlap or compatibility with the national ID card scheme would also have to be considered when designing a national vehicle register, according to PA Consulting.

Long-term funding of the ANPR technology also remains an issue. The year-long trial cost £12m, which was partly funded by £1m recovered by police using the technology. But the report admits this would not cover the cost of the full-time police needed to operate the technology and carry out the vehicle checks.

A spokeswoman for the DVLA said a number of improvements have been introduced since the report to ensure a greater level of accuracy in the data supplied to police and that when the DVLA links to the CJX around the middle of next year the situation will improve further. She claimed that since the PA Consulting repor the accuracy of one of the DVLA database is assessed at 92 per cent in terms of tracing registered keepers.

"We believe that these developments address the concerns expressed by the PA Consulting report. They will enable the Agency to provide full support for the police ANPR system which is perceived as a high priority within the Agency," she said.