Speed cameras have always been on the radar of motorists and a key to their frustration and anger, despite knowing that they are really very effective to reduce injury and death rates on the roads. Is it actually true?
Of course speed enforcement cameras save lives. Let’s assume how effective it is. Figure out the casualties have been recorded over a certain period at any place, maybe 2 years. Install the speed enforcement camera system and again measure casualties over the same period. If there is any improvement in safety, it is because of the camera. But is it really as simple as it seems? There are several other factors which play their part due to which cameras seem to be more effective. When it comes to evaluating the effectiveness of speed cameras on road safety, such factors are usually overlooked.
Over the past few decades, the road safety organizations have installed speed enforcement cameras at many places in the UK. Every year, these cameras catch over 800,000 drivers while speeding. However, cameras have been criticized as another tactic by the government to make money instead of an approach to avoid accidents and injury and deaths, according to road safety companies. It is because of the minimum penalty of £100 for speeding. According to a recent estimate, around 190 lives could be saved annually and serious injuries could be reduced by 330 and collisions by 1130 in the UK. As a result, it could save up to £21 million.
What statistics have to say?
Usually, authorities take decisions to install a camera when they see increasing cases of accidents at a specific place over a period. Well, these high numbers are not enough to tell that the area is potentially dangerous and needs proper treatment. It is not just because of random blips in where and when these accidents happen.
There are chances of accidents found in road safety data at an area to reduce the risks in their number, without applying any treatment, for example speed cameras. This is known as RTM or Regression-to-the-mean effect.
We also understand that the long term accident cases have been down because of certain factors like better driver training and improved safety regulations. When it comes to observing the lower rate of casualties at an area after installing a camera, it is important to find out how much the RTM effect has been observed? How much effect is because of general road safety trends? And how much is the camera responsible for that?
The trend and RTM effects vary between areas of camera placement. When looking at some sites where these cameras are installed, RTM effects can be responsible for reduction. It indicates that there is no impact at this place. Traditional approaches may be overly optimistic to determine the impact on accidents by cameras. It has clear implications when it comes to looking at value for money and whether better return has been achieved on investment.
What is even more complicated?
We are not saying that using speed enforcement cameras have no benefits on road safety. They could have a great impact in preventing the costs of medical treatment due to road traffic accidents. But it is important to apply more strict approaches to get the information and avoid bias.
It is also not wrong to say that speed cameras can alert the drivers to follow the traffic rules and maintain speed limits to avoid penalties when they get caught in speeding. Hence, cameras can have a more beneficial and general impact on safety conditions. Capturing the positive impact accurately is a lot simpler from the data.
Sadly, this situation has been made complex due to the presence of cameras. It may cause some drivers to drive harshly when getting closer to the camera. For example, they may break heavily which can lead to crashes. Even worse, half of the speed cameras may not be active and the situation is a lot more complex.
You often need proper knowhow of advanced statistics in order to figure out the trend and RTM effect. It may not be available all the time in the team for road safety. So, it may be the confounding factor which may not be consistent nationwide. Software is being available readily to figure out the road safety but it is not that easy.
Other works have been done to come out with a more proactive approach instead of reactive to know the sites with issues relating to road safety. It would guide future decisions for investment on the basis of predicted collisions at areas.