Work with offenders on interesting (and counter-intuitive) new research

If you park your car on the street and some of your street lights weren’t working, you might think you’d better get on to the council quick and get them fixed before someone broke into your car overnight.

However, new British research suggests you might be better ringing up the council and get them to turn off all your streetlights after midnight. A new article published today in the Journal of Quantitative Criminology led by Dr Phil Edwards of the London School of Hygiene and Tropical Medicine (which you can read here – unusually for most research, the article is free-to-access for the general public ) found that switching street lights off at midnight was strongly associated with a reduction in night-time theft from vehicles when compared to day time thefts. Interestingly, when the data were adjusted for changes in daytime thefts, night-time theft from vehicles increased in neighbouring roads where street lighting continued to be left on.

The reason that this research is interesting is that there is a strong tradition within the situational crime prevention literature that poor lighting levels are associated with more crime.

A systematic review of the evidence (essentially analysis of a range of different studies) in 2008 concluded that improvements in street lighting could reduce crime. In the 13 studies which were analysed for the review, both violent and property crime was seen to reduce by around 21 per cent compared to areas that did not receive improved street lighting. The review identified that effects were likely to be greater if the previous street lighting provision was particularly poor. In addition, the review found that street lighting improvements were associated with greater reductions in the UK than the US, and that property crime reduced more than violent crime in treatment areas.

Until recently research has overwhelmingly focused on the effects of improved street lighting. Although, it should be noted, that in other fields, improved street lighting has been criticised for producing light pollution which adversely affects the sleep of animals and humans, and for the increased energy it requires and negative impacts on climate change.

The research 

However, much of the previous research focused on the links between street lighting and crime over quite wide geographical areas. This study focused on a case study area for which detailed street lighting and police recorded crime data were available. This enabled the researchers to examine changes at an individual street level for both those streets along which changes to street lighting were implemented, those adjacent to them, and to contrast changes for hours of daylight and darkness.

The research looked at police recorded crime data from Thames Valley Police for almost a decade (April 2004 to September 2013) which included records for 57,918 thefts from vehicles.

The most interesting finding from the study suggests that, in the case of part-night lighting (PNL), after accounting for changes in crimes committed during the day, theft from vehicles reduced on street segments along which street lighting was switched off at midnight, but that these crimes may have been displaced at night to better-lit streets nearby.

The researchers have sought to identify the reasons for this apparently paradoxical finding. They suggest, firstly, that because stereos and Sat-Nav systems are now built in, thieves are looking for other valuables to steal (laptops, tools etc.) and the lack of light makes it hard for them to see whether such items are in a particular car. Secondly, the researchers say that if thieves are intending to remove hub caps, wheel trims or number plates, they need some form of light to do this and using their own lights may alert local home owners and makes them feel vulnerable to being apprehended. Unfortunately, this does not seem to mean that thieves give up, merely that they move on to nearby streets which are better lit to target the vehicles there.