Enhanced Street Lighting Research Centre

Yes. Half a century worth of research shows that enhanced street lighting has a positive effect in reducing crime. In one study, when all data is considered together, enhanced street lighting was associated with a relative reduction in crime of 21 per cent in areas it was introduced, compared to similar areas where there were no such improvements.

Research overwhelmingly reinforces the view that enhanced street lighting is an effective way of dealing with crime and disorder problems. In fact a systematic review¹  looked specifically at studies from the UK and found an even greater effect there than in the USA.

You can therefore be confident that enhanced streetlighting is a useful mechanism in reducing crime. There was no evidence that introducing street lighting meant more crimes were reported (as criminal activity was now easier to see).

1 Welsh, B., and Farrington, D.F. (2008).

There are two main explanations for why improving streetlighting reduces crime.

1. By its very presence improved street lighting helps to increase surveillance, ‘guarding’ locations and deterring potential offenders.Better street lighting increases the risk of identification for offenders, it encourages more people to use public spaces, increasing the number of potential witnesses to any offence and making it less likely an offender can escape without being identified and later recognised. Routine Activity Theory (RAT) suggests that offenders follow a routine when offending and that if you can interrupt that routine, you canstop further offences. RAT states that when for crime to occur, three things need to happen at the same time and in thesame space:s A suitable target is available – person, property etc.s There is the lack of a suitable guardian to prevent the crime from happenings A likely and motivated offender is presentThe theory suggests that if you change any of these then youcan discourage potential offenders from offending. Enhanced street lighting can act as a “suitable (or capable) guardian”and reduce the likelihood that a likely and motivated offender will be present.

2. Improved lighting signals investment in the community, increasing community pride and informal social control – and thus reversing the ‘broken windows’ effect. The broken windows hypothesis²suggests that physical dilapidation in an area gives the impression that ‘nobody cares’ and thus no one will intervene against crime and disorder. Improving the environment displays ‘civic pride’ that demonstrates how much local people care about their locality. The installation of enhanced street lighting can make a location more welcoming which may in turn increase informal social control.

2 Cohen and Felson (1979)
3 Wilson and Kelling (1982)

Studies from the US showed no clear tendency for some types of crimes to decrease more than others after the introduction of improved street lighting.

However, studies in the UK showed that improved lighting was followed by a significant reduction in property crime but not in violent crime. In the UK the review has shown enhanced street lighting to be particularly effective in relation to property crime. The studies showed that it was effective against all types of property crime and particularly burglary and vehicle crime.

No. The positive effects of improved street lighting are felt in the day–time as well as at night.

Though you might expect enhanced street lighting to only have a significant impact on crime during the hours of darkness, the evidence actually shows that enhanced street lighting also brings about reductions in crime during daylight hours as well. Street lighting seems to help reverse the ‘broken windows’ effect. The suggestion is that by improving street lighting in an area, the local community develops a greater sense of civic pride in their area and are more likely to protect it at all times. In other words, it can act as a catalyst for community action and cohesion. The community see that others are concerned about their area (by installing better street lighting) and begin to take a pride in the area themselves.

In two major studies from the UK⁴ there is clear evidence that improved street lighting led to increased community pride, which in turn led to further environmental improvements, which in turn led to greater community pride. In other words, improved street lighting started a ‘virtuous spiral’. You should not, therefore, just think of improved street lighting as an intervention that can only target night-time crime.

It obviously has an impact in relation to such crime, but it should also be considered as a mechanism to help develop a sense ofcommunity pride, either on its own or as part of a package of measures.

4 Painter and Farrington (1997, 1999a)

No, indeed the reverse appears to be true: enhancing street lighting seems to benefit surrounding areas. One study in the review tested for displacement of crime and diffusion of benefit from introducing better street lighting. The study in Stoke-onTrent⁵ discovered that crime was reduced not only where street lighting was enhanced but also in an adjacent area. In the non–adjacent ‘control area’, there was no such reduction. So rather than shifting crime to another area, improved street lighting appeared to spread its benefits to another area.More research needs to be done to further test this finding, but it does suggest that improved street lighting might actually benefit those who live in areas not directly affected by it. In this particular case, it was suggested that improved street lighting had caused a “spill over” of community pride into a neighbouring area, which led to stronger informal social control and better community cohesion, which in turn deterred potential offenders.

5 Painter and Farrington (1999a)

Yes, it is. Where street lighting has been improved or implemented, cost–benefit analysis indicates that its benefits hugely exceed its costs. The review found that two UK studies⁶ provided cost benefit analysis, both showing that thefinancial savings from reduced crimes greatly exceeded the financial costs of the improved street lighting.

They found that investing in improved street lighting led to:
• A significant reduction in crime.
• Fewer property crimes resulted in less property being stolen,
• Fewer properties requiring repairs,
• Fewer insurance claims, and
• A reduction in the wider impacts upon some victims (e.g. lost days atwork to deal with the incident).

Obviously, these benefits accrued over time; they were not instant.

Yes. A significant body of research indicates that low lighting conditions contribute to a disproportionate number of fatal road traffic injuries. Statistics show that although fewer miles are driven at night, more than half of all traffic deaths occur during this time. The severity of injuries, defined as the ratio of fatal collisions per 100 collisions, is consistently higher at night, particularly on roads without adequate lighting. For example, injury severity is nearly three times higher on roads with no lighting compared to well-lit roads.

There are several physiological reasons why low lighting conditions increase the likelihood of road traffic casualties:

Reduced Visual Performance: Under dim lighting, our vision is mediated more by rod photoreceptors, which are less effective at processing visual information quickly. This leads to slower reaction times when drivers need to perceive and respond to hazards, such as other vehicles or pedestrians.

Increased Stopping Distances: Slower reaction times under low luminance conditions translate into longer stopping distances. For example, a modest delay in visual processing can result in a significant increase in the distance required to stop a vehicle, making it harder to avoid collisions.

Yes. Research demonstrates that the presence of street lighting can significantly reduce the severity of road traffic injuries. In both the UK and Greece, the introduction of street lighting led to approximately a threefold decrease in the severity of injuries, despite the countries having different overall injury rates. This suggests that improving road lighting is an effective measure in reducing serious injuries and fatalities on the road.

Street lighting improves road safety by:

Enhancing Visibility: Good lighting conditions allow drivers to detect and react to hazards more quickly, reducing the likelihood of collisions.

Reducing Visual Reaction Times: With better lighting, visual reaction times are faster, which decreases the stopping distances required to avoid accidents.

Increasing Awareness: Well-lit roads make it easier for drivers to accurately judge the speed and distance of other vehicles, particularly at intersections and junctions where such judgments are critical.

Yes, it is. Where street lighting has been improved or implemented, cost–benefit analysis indicates that its benefits hugely exceed its costs. The review found that two UK studies⁶ provided cost benefit analysis, both showing that thefinancial savings from reduced crimes greatly exceeded the financial costs of the improved street lighting.

They found that investing in improved street lighting led to:
• A significant reduction in crime.
• Fewer property crimes resulted in less property being stolen,
• Fewer properties requiring repairs,
• Fewer insurance claims, and
• A reduction in the wider impacts upon some victims (e.g. lost days atwork to deal with the incident).

Obviously, these benefits accrued over time; they were not instant.

Yes. The installation of street lighting has been shown to be a cost-effective measure in reducing road traffic casualties. The benefits, including reduced fatalities and serious injuries, far outweigh the costs associated with installing and maintaining road lighting. The economic savings from fewer accidents and the reduced burden on healthcare services further highlight the value of investing in street lighting.