Do speed cameras improve road safety?

Speeding has been widely recognized around the world as a major cause of road accidents and fatalities. As a result, speed limits are imposed in many countries to control the speed of vehicles. One of the widely used speed enforcement methods is the speed camera that may be fixed permanently or temporarily at locations assigned as speed camera areas. Despite their widespread use, the effect of speed cameras on road safety has received relatively little attention in the literature. Using data from 24 speed camera zones in Christchurch, New Zealand, this paper compares the accident rates of these sites before and after the establishment of these speed camera zones with the corresponding rates of non-camera sites in the same city.