New figures released by the Department for Transport (DfT) have shown an increase in the number of people injured at some speed camera sites in England, compared with casualty rates before the cameras were put in place.
However at some sites, speed cameras were reported to have helped decrease casualty rates, revealing a mixed picture of the cameras' performance in different parts of the country.
Neil Greig, director of policy and research at the Institute of Advanced Motorists, said: "This data must be used with care. The best speed cameras deliver lower speeds and fewer casualties without catching lots of drivers out."
RAC motoring strategist Adrian Tink said: "We're pleased to start seeing this type of information being issued - it's long overdue.
"But unless this information is acted upon by local authorities then it becomes a pointless exercise. We've long called for a full audit of individual speed cameras, ensuring we keep the cameras that make a difference and replace those that don't with other safety measures if needs be."
Copyright © Press Association 2011