Introducing Arup's view on CPTED

1. Chris Tomlinson
Arup Resilience, Security and Risk
October 2011
CPTED – An Introduction and its
role in Built Environment Security

2. Agenda
 Definition & Intent
 Theoretical Background
 Concepts and Language
 Good and Bad Practice
 Examples
 Realities and Criticism of the Approach
 Futures and Compatibility
 Sources

3. CPTED Definition
“The proper design and effective use of the built
environment that can lead to a reduction in the fear and
incidence of crime and an improvement in the quality
of life.
The goal of CPTED is to reduce opportunities for crime
that may be inherent in the design of structures or in the
design of neighbourhoods.”
Crowe 2001

4. CPTED Intent
 The theory of CPTED is based on a simple idea i.e. that
crime results partly from the opportunities presented by
physical environment.
 CPTED is the design or re-design of an environment to
reduce crime opportunity and fear of crime through
natural, mechanical, and procedural means.
 CPTED is best applied with a multi-disciplinary
approach that engages planners, designers, architects,
landscapers, law enforcement and (ideally)
residents/space users.

5. The Focus is Conventional Crime
Crime
Violence against the
person
Theft/robbery
Burglary
Fraud
Vandalism
Civil Disorder
Anti-capitalist
Single issue
Fixated individuals
Anti-brand
Nuisance
Begging
Rough sleepers
Substance abuse
Fly posters
Although CPTED techniques do assist in anti-terrorism, but to what degree is
hard to measure

6. Using Realistic Risk-driven Design

7. Theoretical Background
 It was first coined as a term by the US criminologist, C. Ray Jeffery in 1971 -
arguing that sociologists had overstated the social causes of crime e.g.:
deprivation and other sub-cultural influences; and had neglected biological‟
and environmental determinants; other influences include:
- Defensible Space, promoted by the US architect Oscar Newman; a famous critique
of American public housing at about the same time as Jeffery‟s book. Newman put
much of the blame for the high crime rates in public housing “projects” on their lay-
out and design. Also influenced by Jane Jacobs and her belief in diversity of street
use
- Situational crime prevention, developed by the UK government‟s criminological
research department in the mid-1970 to 80. Unlike CPTED, and “defensible space”,
this approach is not concerned principally with architectural design and the built
environment
- Environmental Criminology „Broken windows‟ theories on decay driving crime and
nuisance
 Most of the academic research into the relationship between crime and
environmental opportunities has been conducted under the rubric of
situational crime prevention.

8. Situational Crime Prevention
 But CPTED is not operationlised “situational crime prevention”,
which is:
- Target Hardening - reducing criminal opportunities by making the
situation or property less vulnerable (car steering locks)
- Target Removal - using cheques instead of cash
- Removing the means to commit crime - gun law control
- Reducing Pay Off - marking goods
- Formal Surveillance - police patrols
- Natural Surveillance - building houses to overlook one another
- Surveillance by Employers - managers in public housing
- Environmental Management - good liaison between football clubs and
police in preventing fan violence.
 However, there are design crossovers e.g. Target Hardening,
Natural Surveillance and Environmental Management.

9. Criminal Opportunity
Location, including capable
guardianship
Vulnerable TargetMotivated offender
“Individual criminal events must be understood as confluences of offenders, victims
or criminal targets and laws in a specific settings at particular times and places“.
Brantingham and Brantingham, Environmental Criminology (1981)

10. The Nature of Crime Targets - CRAVED goods
Based on Ron Clarke‟s concept of „Hot Products‟ – those at
heightened risk of theft by virtue of being „CRAVED‟ i.e.
having one or more of the following properties:
- Concealable
- Removable
- Available
- Valuable
- Enjoyable
- Disposable

11. Some Realities on Offending Behaviours
 CPTED measures (many rely on psychological cues) may not be
that obvious to potential offenders e.g.:
- Derelicts
- Buccaneers – attention seekers
- Situation exploiters – mass and event
- Alternate cultures – graffiti artists, skate boarders, PK Traceurs etc
 CPTED is undermined by post-offence inaction
 Must be risk-based i.e. CPTED applied without a full
understanding of the micro, meso and macro-crime patterns is
pointless – well at least the micro-crime patterns
 Displacement in space, time and target
 Fear of crime and recitations of pre-conceived ideas i.e. too
much emphasis on „broken windows‟ as a signal of societal
failure

12. CPTED Principles
Territoriality
Natural Surveillance
Access Control
Target Hardening
Image Maintenance
Activity Support

13. Good Practice
 Planning obligations – e.g. Crime prevention and the
assessment of development applications under section 79C of
the NSW Environmental Planning and Assessment Act 1979
 Architect engagement – the US has reached out to AIA and in
the UK police ALO/CPDAs are engaging RIBA audiences
 International CPTED Association – US/Canada/Australian/NZ
 Designing out Crime Association – UK
 Europe – EU programme maturing, but has not researched
success

14. Bad Practice
 Overstating CPTED Effectiveness – e.g. CCTV or lighting
effectiveness often overplayed
 Unhelpful affiliation with design – making the CPTED fit the
design and genuinely independent advice could conflict with
commercial interests (commoditisation of security advice)
 „Boilerplate‟ not always transferrable – „Cookbook solutions‟
 Lack of follow-on assessment of design measure effectiveness
– operability and tuning
 Failure not admitted to – CPTED failure and context should be
recorded it will develop knowledge

15. Territoriality

16. Territoriality Explained
 Unambiguously define edges between the various types of
spaces and uses
 Create clarity of purpose and use
 Prevent flow-through circulation routes that connect outside
(public) spaces
 Not be „shy‟ about making some edges physically impenetrable
 Keep the public in public types of spaces and out of the private
ones
 Lay claim to semi-public spaces by encouraging residents to use
them.

17. Natural Surveillance

18. Access Control

19. Target Hardening

20. Image Maintenance

21. Activity Support

22. Think Offender and Nuisance in the Space

23. Does CPTED Work?
 Cozens found it to be a qualified yes
- CPTED components of surveillance, access control, territorial
reinforcement, activity support, image/ management, target hardening all
individually contribute to reducing crime & fear in broad range of studies
- CPTED shown to reduce crime and the fear of crime in numerous
evaluations and to increase property values and investment in the area
 However:
- Support for the effectiveness of comprehensive CPTED projects has not
been unequivocally demonstrated
- Uncertain precisely how CPTED and its component parts work, where it
works best and how to systematically evaluate its effectiveness (or
otherwise) beyond reasonable doubt
- Rigorous testing and evaluation procedure to produce deeper understanding
of theoretical basis of CPTED mechanisms
- Uncertain precisely how CPTED and its component parts work, where it
works best and how to systematically evaluate its genuine effectiveness

24. CPTED and Problems
 It is prone to fashion and drift of meaning, and meaning different
things to different agencies or disciplines
 It is „in a disciplinary No Man‟s Land‟:
- It is isolated empirically and theoretically from rest of crime prevention,
even situational prevention
- Lack of criminological rigour/clarity
- Basic concepts need further investigation (e.g. the effects of territoriality
may not be universal
- The theory has not been integrated – the four strands (Defensible Space,
CPTED, Situational Crime Prevention, Environmental Criminology) are
simply placed side-by-side, requiring the user to fit them all together. This
is inappropriate complexity masquerading as simplicity
- Evidence base needs developing on detailed risks of crime addressed by
CPTED, causes/ consequences/ interventions

25. Alternative Practices
 Accommodating behaviours that
might be acceptable
 More space-user CPTED tuning
 Landscape manipulations
 Second generation CPTED

26. Think Design-based Solutions
 Promote acceptable behaviours
and space use
 Test solution even as a desk-top
multi-disciplinary exercise
 Think sustainability,
maintainability and aesthetics

27. Think Fear of Crime
“Gradually fear extends its domain in the city, with a
preference for open spaces. Rarely does it retreat from
conquered ground, and in exchange it takes new ones to add
to its domains. It is we who retreat, we who give way, we
abandon a space which is left at the mercy of fear.
Sometimes we resist, we fight back, we suffer the anxiety
rather than lose a space that is ours, though in the end we
will give the position up, we will not set foot in that part of
the park again after dark, we will avoid those
neighbourhoods, we will not walk so carelessly in outlying
areas, we will take a taxi instead of the underground after a
certain hour”.
Isaac Rosa (2008). El país del miedo

28. 28
The Arup Approach
Architects Client/users Developers
Early Engagement (risk-led) by Security Consultants

29. 29
We Should use CPTED to:
 Reduce the probability of crime and nuisance, whilst enhancing
the quality of life through community safety
 Use opportunities in planning and design of the built-
environment on a range of scales and types of place from
individual buildings and interiors to wider landscapes,
neighbourhoods & cities
 Produce designs that are 'fit for purpose„, and contextually
appropriate in all other respects
 Whilst achieving a balance between:
 the efficiency of avoiding crime problems before construction
 and the adaptability of tackling them through subsequent
management and maintenance
 To compliment our sustainable approach to projects.

30. Sources – not an exhaustive list
 Academic – Clarke, Cozens, Ekblom, Jeffery etc
- Theoretical Background to CPTED and Situational Prevention, Ronald V
Clarke, 1989
- Crime prevention through environmental design: a review and modern
bibliography Paul M Cozens, 2005.
 Government:
- US – State CPTED networks
- Canada – Province CPTED networks
- Australia – State and territory guidance (Victoria, NSW and Western
Australia)
- EU – European Crime Prevention Network (EUCPN)
- UK – The ACPO Secured by Design scheme
 Associations and Conference proceedings – These need to be
looked at or listened to only by the hardiest, as often there is
critique that may be hard to put in context

31. Chris Tomlinson
chris.tomlinson@arup.com
Any Questions?