Do brighter street lights make you safer from crime?

Today, Labour Shadow Home Affairs minister Stella Creasy called for a halt to street-light switch off programmes in England and Wales, citing concerns that darker streets could result in an increase in crime and the fear of crime. She called for a halt until studies can be carried out on the potential risk.

Fortunately studies have been carried out that begin to address this issue.

The National Criminal Justice Reference Service (US) carries a 1979 report titled “Street Lighting Projects – National Evaluation Program Phase 1 Report” in the abstract for which it is stated that:

while there is no significant evidence that street lighting affects the level of crime, there is a strong indication that increased lighting decreases the fear of crime.

Following on from that study, other studies have since addressed the connection between lighting and crime.

For example, this report from 2000 (pdf), written by the Illinois Criminal Justice Information Authority, studied the effect of increased lighting levels in Chicago alleyways. The report begins:

In October of 1998, the Mayor’s Office in the City of Chicago and the Department of Streets and Sanitation began a multi-stage plan to reduce crime through improved street and alley lighting. The first part of the plan sought to upgrade and improve the city’s 175,000 streetlights, which illuminate the arterial and residential streets. The second part of the plan involves repairing and upgrading the lighting in and around viaducts and Chicago Transit Authority stations. The final part of the plan has been to boost lighting levels in alleys across the city as a tool for public safety and fighting crime. In the past, 90-watt lights illuminated most city alleys and the Department of Streets and Sanitation have increased alley lighting levels by installing new fixtures that can accommodate 250-watt bulbs. The intent of the City’s program was to increase feelings of safety and decrease crime in the alleys surrounding Chicago’s residential and arterial streets by increasing the wattage and number of alley lamps.

Once the lighting had been changed (made brighter) the report found that:

when the number of reported incidents for this one year analysis are examined, the data indicated that there were 428 total incidents reported in the pre-installation period and 519 total incidents in the post- installation period – an increase of 21 percent in reported offenses between the pre- and post-period test.

Each of the three crime categories experienced an increase in the number of reported incidents between the pre and post- installation period. Violent Index offenses increased 14 percent (119 to 136), property Index offenses increased 20 percent (30 to 36) and non-Index offenses increased 24 percent (279 to 347).

The city of Santa Rosa in California is carrying out and evaluating a street light reduction program between 2009 and 2012, the introduction to which states that:

Several academic studies have been published on the correlation between street lighting and crime. None of the studies make a direct correlation between increased street lighting and reduced crime. In fact some of the research indicates just the opposite, noting that the introduction of street lighting actually increased the occurrence of crime as perpetrators could monitor their actions without the use of flashlights or other lighting tools which could highlight the individuals’ presence.

The Santa Rosa 2009/10 crime statistics (pdf) show a decrease of a few % in both violent crime and property crime between 2009 and 2010 which matches the general trend across the USA.

Other studies will continue to shed light on this matter but at present it seems that, at best, increased light at night reduces fear of crime, but at worst may actually increase the crime rate. After all, criminals need light in order to commit crimes.

Thanks to @darkskyscott of the International Dark-sky Association for links to these reports.