outdoor lighting and crime, part 1 - Astronomical Society of Victoria

changes in recording procedures and inadequacies of available data.” More details would
have been helpful.
In the case of pedestrian and resident interviews done specifically to determine whether
‘improved’ lighting has affected crime, bias could arise from the wording or order of questions,
despite the use of ‘double-blind’ procedures. In particular, the effect of brighter lighting
in reducing fear of crime (see Chapter 6 below) and the common belief that lighting reduces
actual crime could possibly bias recollections of crime. Places that were less brightly
lit at night might seem more prone to crime. Any such bias could possibly apply to the
places in daytime as well as night. Reliance on interviews could therefore have contributed
to the difference between the Painter and Farrington results and the generally smaller or inconclusive
effects found by other researchers using recorded crime data. In the absence of
resolution of this issue, it could be argued that inclusion of complete figures for recorded
crime should have been a condition for publication rather than an option.
There are other problems with Painter and Farrington (1997), including bias in the literature
review. From the time when the experiment was done (ca 1992) to the time of
publication, it was not justifiable to claim that a consensus on a beneficial effect of lighting
on crime had been established in the journal literature. A beneficial effect may have
been the result reported in Painter’s unpublished PhD thesis of 1995, but as is stated in the
acknowledgement section of the paper, the thesis included the same (Dudley) experimental
results. The literature review and the rest of the paper therefore should have been neutral in
its approach to the topic. Instead, it is strongly biased towards the view that lighting does
prevent crime, as is shown by the following quotes from the paper:
“The main aim of this project is to investigate the effects of improved street
lighting as a crime prevention technique.”
It should have been a test for any effects of lighting changes on crime measures. As it
stands, it pre-empts the results of the experiment.
“Modern interest in the relationship between street lighting and crime began in
North America amidst the dramatic rise in crime which took place in the 1960s.”
This was a time when street lighting was also increasing dramatically, but that is not
mentioned.
“In summary, the relationship between visibility, social surveillance and criminal
opportunities is a consistently strong theme to emerge from the literature.”
This is based on Situational Crime Prevention theory, not experimental results. Taking
it to its logical conclusion, there should be little crime in daytime, far from what actually
happens.
“This design controls for the major threats to internal validity outlined above.”
No, an increase in lighting as a treatment should be counterbalanced in some way, such
as by a decrease in lighting of similar magnitude as a simultaneous treatment in another
experimental area, or, less effectively, a subsequent return of the lighting levels in the experimental
area to their original values.
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