UK Edition
Switching off street lights after midnight reduces car theft by half, a government-funded study has found, as thieves are deterred by the darkness.
The research, funded by the National Institute for Health Research (NIHR), found that part-night lighting (PNL) where street lamps are switched off from midnight to 5am, reduced thefts from cars from 12 per street, every month, to six per street.
By contrast, there was a 1.5 times rise in vehicle crime on nearby streets where the lighting remained on all night, suggesting some criminals moved to better-lit areas, according to the researchers. Theft of vehicles was also reduced although the researchers said this was not statistically significant.
There was no evidence that street lighting changes had any impact on violence, robbery or residential burglary which remained at similar levels, according to the study by the London School of Hygiene and Tropical Medicine (LSHTM) and UCL.
Cost of crime outweighs the benefit
Dr Phil Edwards, who led the research, said: “It is possible that when lighting is switched off after midnight, offenders consider that the costs of committing a crime, such as using a torch that could raise suspicion among residents, outweighs the benefits.
“When lighting is switched off after midnight the streets are likely to be in near darkness, which means that any would-be offenders may find it challenging to see if there are any valuable goods left unsecured in vehicles, so offenders may choose to move elsewhere to fulfil their intentions.”
Previous studies have suggested that improved street lighting can reduce burglaries and graffiti by an average of 17 crimes per 100. For violent crime, there were an average of nine fewer crimes per 100 in areas with better lighting, according to US research cited by the College of Policing (CoP).
However, the research also suggested that improved lighting in a street appeared to have a more significant impact on crime rates during daylight hours, rather than at night. “For night-time crime only, no fewer crimes were observed in areas with improved street lighting,” said the CoP.
The CoP suggested this could be due to increased-visibility encouraging more people to use the streets, making it less attractive as a target for criminals, and the fact that investment in street lamps showed it was a stronger, more community oriented neighbourhood.
The NIHR research was commissioned to investigate “part-night” lighting that has been widely introduced by local councils to save energy costs and reduce carbon emissions on quiet, urban residential and rural roads, which have very little use after midnight.
“Our previous research showed that switching off street lights at night does not increase crime. This new study suggests switching off street lights between midnight and 6am may actually reduce some types of crime,” said Dr Edwards.