Outdoor Lighting and Crime - Amper

There appears to be no compelling evidence for any appreciable net direct beneficial effect of
increased outdoor lighting in reducing actual crime at night or for net indirect beneficial
effects by night or day.
9.4 GROWTH OF LIGHTING AND CRIME IN THE TWENTIETH
CENTURY
Time-series recorded crime rate data for latter parts of the twentieth century are available for
Australia, Canada, New Zealand and the USA, and for the whole century for England plus
Wales. Crime rates and representative skyglow growth curves are positively correlated in
each of these five countries. These are massive datasets, with virtually no sampling error.
The shortcomings of recorded crime data, as opposed to surveyed crime data, are
acknowledged, however.
Positive correlations with notional or actual skyglow growth would appear likely to apply in
15 other countries for which recorded crime data are available and apparently free from large
discontinuities and other anomalies.
The crime data sets cover national populations and durations from decades to a century. A
slight weakness in the analysis is the need to use calculated skyglow growth curves based on
observations, although the curves do cover a century and are consistent with three decades of
ground based measures from Italy, various measures from the USA, a decade of global
observations by satellites, and many incidental observations by amateur astronomers.
9.5 DARKNESS AND CRIME
As demonstrated during the prolonged Auckland electric power disruption of 1998 and in
shorter power disruptions in New York in 1965 and 1977, darkness actually inhibits crime.
The presence of urban infrastructure by itself, unlit or dimly lit, has not maintained the urban
crime rate. This is contrary to assertions in the crime prevention literature.
Deliberate reductions of street lighting in some US towns and a suburb have not resulted in
reported increases in crime or road traffic accidents. Amherst, NY has consistently been
ranked as the safest or one of the safest suburbs in the USA. It has had stringent outdoor
lighting controls for over forty years for the purpose of avoiding light-related disturbance of
sleep at night.
Reports of Dark Campus and similar programs and casual observations indicate that graffiti
and probably other forms of vandalism are deterred by darkness. Such programs are well
overdue for rigorous scientific scrutiny, however.
The data sets used in investigating darkness and crime cover populations of thousands to 9
million and dark durations from a single night to many thousands of nights.
9.6 LIGHTING AND CRIME RELATIONSHIPS
In the USA, urban crime rates well exceed suburban crime rates, which, in turn, well exceed
rural crime rates. Similar progressions occur in other countries. Generally, urban centres are
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