Published: 31 March 2022
Fewer cars are broken into at night on roads with ‘part-night’ lighting (PNL), where street lights are switched off between midnight and 5am, finds new NIHR-funded research.
Researchers, led by the London School of Hygiene & Tropical Medicine (LSHTM) and University College London (UCL), examined detailed police recorded crime data from Thames Valley Police and data on changes to street lighting from April 2004 to September 2013.
The LANTERNS study found that the rate of thefts from cars at night was halved in streets with PNL compared to the same streets before PNL. Car break-ins decreased from an average of 12 per street per month before PNL, to six per street per month after PNL was introduced.
This coincided with a similarly significant 150 per cent increase in vehicle crime on nearby streets where the lighting remained on all night, suggesting some criminals are deciding to move to better-lit streets nearby.
However, fewer crimes were ‘displaced’ to these nearby locations, meaning an overall net reduction in crime. Vehicle theft was also reduced but this was not statistically significant.
There was no evidence that lighting changes were associated with changes to the levels of violence, robbery or residential burglary.
The results are now published in the Journal of Quantitative Criminology.
Dr Phil Edwards, LANTERNS Project Leader, from LSHTM, said: “Many local authorities in the UK have introduced part-night lighting on quiet, urban residential roads and rural roads, which have very little use after midnight, to save energy costs and reduce carbon emissions. However, safety concerns about this policy have been raised.
“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.”
The team evaluated the impact on crime from changes to street lighting at street level. In contrast to previous studies, the changes to street lighting involved reducing rather than increasing lighting provision. Three different types of lighting changes: PNL, dimming, and white light were examined for five crime categories: residential burglary, robbery, vehicle crime and violence.
The team used crime data from Thames Valley Police, together with data on changes to street lighting in the local authorities in Oxfordshire, Reading, West Berkshire. Over the ten-year study period there were 283,275 crimes, of which 79,000 (28%) were vehicle crimes.
After controlling for the underlying long-term and seasonal trends in crime, the team found theft from vehicles considerably reduced on street segments where street lighting was switched off at midnight.
Dr Edwards added: “We didn’t set out to find the reasons for the observed changes, but 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 would likely raise suspicion among residents and risk being witnessed, outweigh 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.”
The LANTERNS project was funded by NIHR’s Public Health Research (PHR) Programme.