South Yorkshire has become the latest local authority to trial turning off speed cameras in an attempt to save money, it has been revealed, despite police insistence that they are vital to road safety.

Four cameras – all of them in Rotherham – have been taken out of commission to enable the council to monitor whether driving habits change after they have been switched off.

When speed cameras were turned off in Oxfordshire at the end of July, it was found that the number of drivers speeding at one location previously covered by a camera had increased by 88%.

Inspector Paul Winks of Thames Valley Police told the BBC at the time that those statistics were "disappointing," saying: "It clearly means switching off the camera has given a green light to a small number of people to break the law.” He added: "The consequence is more death and more death is unacceptable."

Recently, it has been reported that Oxfordshire’s cameras are likely to be switched back on, with Thames Valley Police meeting the cost of operating them. The cameras had been turned off after Oxfordshire County Council withdrew £600,000 funding due to the coalition government cutting the Road Safety Grant by 40% from £95 million to £57 million.

Despite the experience in Oxfordshire, South Yorkshire Safety Camera Partnership says that the cameras may be removed on a permanent basis if no increase in speed is observed.

However, local police insists that the trial is a step in the wrong direction where road safety is concerned, with Chief Inspector Stuart Walne, Head of Roads Policing for South Yorkshire Police, telling local newspaper The Star: "Speed cameras are in important asset in helping to reduce the number of people killed and injured on South Yorkshire's roads.

"As a result of the cameras and other road safety initiatives we have seen the numbers of people killed and seriously injured on the county's roads drop to their lowest levels since records began in 1979.

"The cameras are funded by the taxpayer and it is therefore important that they are strategically placed in the areas where they are needed most.

"Through this review, we have identified sites that no longer meet our requirement criteria and will be reviewing these sites accordingly.

"Alternative solutions for decommissioned sites may include use of mobile camera vehicles instead of fixed site cameras, vehicle activated signs and road engineering solutions."

However, Barry Smith, partnership manager for the South Yorkshire Safety Camera Partnership, maintained that the cameras would only be decommissioned permanently if the trial found that there had been no change in drivers’ behaviour.

"As part of the review process, sites that have been identified for possible decommissioning will have speed surveys carried out prior to their removal,” he told the newspaper.

"The cameras will be bagged to determine the affect on speeds of switching off the cameras.

"If drivers’ speeds increase once the trial has started then the cameras will not be removed.

"Some of these sites are legacy sites which were in place before the Safety Camera Partnership came into being.

"As a partnership it is important that the cameras are placed in the areas where the casualty data and speeding statistics show that they are needed most."

