A hi-tech computer system used in the hunt for the killers of PC Sharon Beshenivsky could be costing lives on the region's roads, an expert has warned.

Steve Thornton, chairman of West Yorkshire Road Safety Strategy Group, told the government's Transport Select Committee he was "concerned" police spent too much time focusing on Automatic Number Plate Recognition (ANPR) activities.

But this was at the expense of traditional road traffic duties, such as

officers patrolling in cars, which were an important method of reducing accidents, deaths and injuries, he said.

The system uses cameras to scan number plates so police can check if the driver is wanted, if the car is stolen and if tax and insurance are up-to-date.

Police investigating the shooting of PC Beshenivsky used ANPR to track the owners of a car caught on camera leaving the city. It led to six suspects being arrested in London, although all were later released.

But Mr Thornton, giving evidence to the Commons' powerful Transport Select Committee, which is probing traffic policing, played down the importance of ANPR, described by police as "revolutionary". He said: "There is some concern the police may be spending too much time on ANPR activities at the expense of overall road policing issues.

"Whilst appreciating the value of ANPR operations and the link between criminality and road safety, the over-reliance on ANPR activities could leave major areas of visible roads policing and road traffic enforcement without sufficient attention.

"The general disregard for traffic law, traffic regulation orders, seatbelt

law, etc, by motorists may mirror the way society sees the laws, but it

still contributes significantly to casualty numbers.

Mr Thornton also said West Yorkshire Police failed to spend enough time enforcing road traffic laws because of a lack of cash and officers. Local councils also found it difficult to drum up the money to pay for safety schemes because of the pressures to pay for other things and stay in the black, he said.

He said: "Evidence in West Yorkshire suggests there is insufficient deployment of dedicated roads policing officers to roads policing duties; insufficient resources (staffing, cars and finance) to carry out effective enforcement initiatives; and insufficient equipment to carry out enforcement activities."

Mr Thornton said there had not been "significant changes in recent years" in the number of drink-drivers and said "more resources need to be committed to establish a downward trend".

And he said police had made "little use" of new powers allowing them to

carry out roadside tests on drivers suspected of being on drugs.

West Yorkshire Road Safety Strategy Group is made up of the five councils including Bradford, the police, the strategic health authority, highways

agency and the road safety camera partnership.