"Eyes on the Street' was the fundamental theory which underpinned the classic Jane Jacobs assertion that
a mixture of land uses in combination with provision for open space would reduce opportunities for crime
through increased public surveillance. (1)
Crime prevention is one of many benefits that can result from the development of appropriately designed mixed
use precincts. New Urbanism has prescribed increased opportunities for surveillance, encouragement of social
interaction and a sense of community, as factors which can potentially reduce crime. (2)
Population vs permeability
The presence of surveillance opportunities however, does not immediately guarantee that close and effective
supervision exists. A mixed use precinct alongside open space typically increases the ‘permeability' of the
immediate area. There is a strong argument amongst the criminology literature, (reflected in the Crime
Prevention Through Environmental Design, or CPTED, approach) that more permeable urban environments
actually increase opportunities for crime if there is an insufficient amount of through traffic.(3) One reason is
because the improved walkability and accessible open spaces increase a criminal's awareness space, (4)
allowing for easier identification of targets.(5)
The level of population density and pedestrian use in a redevelopment area is therefore critical to success.
A sufficient mass of local populace and activity helps to ensure that there is in fact a high level of surveillance.(6)
The CPTED approach now encourages social activities which promote diversity and inclusiveness, to engender
a healthier presence upon the precinct as well as create a natural and permanent supervision of the area.(7)
Community participation activities in open space also play a large role in deterring criminal behaviour.
Alternatively, Closed Circuit Television (CCTV) surveillance could be employed in communities suffering from
high crime levels.
Studies in Britain and the United States (8) suggest that both CCTV and natural surveillance in urban spaces
are most effectively deployed as a strategy to reduce property crimes, but are less effective in preventing violent
crimes. Furthermore a 2006 study from the UK (9) demonstrated that increased community interaction is likely
to decrease the incidence of burglary for a sub-area by 45 percent. This was offset by a 30 percent increase in
the risk of burglary due to greater permeability. So in effect, the study concluded that there was a net reduction
of 15% in crimes against property.
Displacement?
The wider geographic effects of crime reduction through design changes have also been a matter for contention.
One major critique of CPTED has been that the crime removed in the immediate sub-area is simply displaced to
a nearby locality instead of being completely removed (10).
However, research in 1994 by Rene Hesseling empirically disproved this theory. (11) Of 55 case studies searching
for evidence of crime relocation following an environmental design initiative, 22 cases exhibited no such trend. 33
cases showed minimal increases of crime in nearby areas, but in no case did the increase in crime elsewhere
equal the reduction of crime in the original location. Thus the consensus amongst criminology literature now
favours the notion that the majority of criminal activity is unlikely to relocate after it is prevented in the original sub-area.
Furthermore in some cases, the study also found that crime in surrounding areas was found to decrease. This
phenomenon, in which the benefits of preventative measures spread to surrounding geographic locations, is more
widely known as a ‘diffusion of benefits'.(12)
In conclusion, the development of a mixed use precinct does not automatically generate a safer environment for
the local area. To offset the permeability effect, the development must establish sufficiently high levels of population
density and pedestrian activity. This is then the key to ensuring that adequate levels of public use and natural
surveillance can be developed - two of the factors which help to discourage crime. If successful, there is likely
to be minimal risk of crime relocation - a diffusion of benefits may even occur, with less crime seen in
surrounding areas.
Footnotes and References
1. Jacobs, J. (1961) The Death and Life of Great American Cities, London, Jonathon Cope.
2. Plater-Zyberk, E. (1993) Five Qualities of Good Design, ANY, No. 1, July/ August, p.12; (Congress for
New Urbanism (2001) Charter for New Urbanism, available from
http://cnu.org/sites/files/charter_english.pdf (acc. March 2011)
3. Rengert, G. (1988) ‘The Location of Facilities and Crime', Journal of Security Administration, Vol. 11,
No. 2, pp. 12-16; Ekblom, P. (1995) ‘Less crime by design', Annals of the American Academy of
Political and Social Science, No. 539, pp. 114-129.
4. Awareness spaces are personal attractors such as parks, private/communal homes, shopping centres,
recreation centres and transport nodes Increased permeability results from the linkages created between
these locations within short distances. (Cozens, P. M. (2008) New Urbanism, Crime and the Suburbs,
Urban Policy and Research, Vol. 26, No. 4, pp. 429-444.)
5. Brantingham,P. & Brantingham,P. (1984) Patterns in Crime, New York, Macmillan.
6. Cozens, P. M. & Hillier, D. (2008) ‘The Shape of Things to Come: New Urbanism, the Grid, and the
Cul-de-sac', International Planning Studies, vol.13, no.1, pp. 51-73.
7. Saville, G. & Cleveland, G. (1997) Second Generation CPTED in Schools, paper presented at the 1st
Annual International CPTED Association Conference, Orland, FL.
8. Welsh, B. & Farrington, D. (2006) ‘Surveillance for Crime Prevention in Public Space: Results and Policy
Choices in Britain and America', Criminology and Public Policy, Vol. 3, No. 3, pp. 497-526.
9. Space Syntax (2006) The Crime and Urban Design Database, Second Report - Advance Final Report,
Prepared for the City of Gosnells, UK.
10.Saville & Cleveland (1997), ibid.
11.Hesseling, R. (1994) ‘Displacement: A Review of the Empirical Literature.' In: Crime Prevention Studies,
vol. 3, edited by Ronald V. Clarke. Monsey, NY: Criminal Justice Press
12.Clarke, R. V. (1997) Situational Crime Prevention: Successful Case Studies, (Second Edition),
Albany, NY: Harrow and Hesto