CPTED an introduction and conceptual framework


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Introducing Arup's view on CPTED

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CPTED an introduction and conceptual framework

  1. 1. Chris TomlinsonArup Resilience, Security and RiskOctober 2011CPTED – An Introduction and itsrole in Built Environment Security
  2. 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. 3. CPTED Definition“The proper design and effective use of the builtenvironment that can lead to a reduction in the fear andincidence of crime and an improvement in the qualityof life.The goal of CPTED is to reduce opportunities for crimethat may be inherent in the design of structures or in thedesign of neighbourhoods.”Crowe 2001
  4. 4. CPTED Intent The theory of CPTED is based on a simple idea i.e. thatcrime results partly from the opportunities presented byphysical environment. CPTED is the design or re-design of an environment toreduce crime opportunity and fear of crime throughnatural, mechanical, and procedural means. CPTED is best applied with a multi-disciplinaryapproach that engages planners, designers, architects,landscapers, law enforcement and (ideally)residents/space users.
  5. 5. The Focus is Conventional CrimeCrimeViolence against thepersonTheft/robberyBurglaryFraudVandalismCivil DisorderAnti-capitalistSingle issueFixated individualsAnti-brandNuisanceBeggingRough sleepersSubstance abuseFly postersAlthough CPTED techniques do assist in anti-terrorism, but to what degree ishard to measure
  6. 6. Using Realistic Risk-driven Design
  7. 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 critiqueof American public housing at about the same time as Jeffery‟s book. Newman putmuch 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 streetuse- Situational crime prevention, developed by the UK government‟s criminologicalresearch department in the mid-1970 to 80. Unlike CPTED, and “defensible space”,this approach is not concerned principally with architectural design and the builtenvironment- Environmental Criminology „Broken windows‟ theories on decay driving crime andnuisance Most of the academic research into the relationship between crime andenvironmental opportunities has been conducted under the rubric ofsituational crime prevention.
  8. 8. Situational Crime Prevention But CPTED is not operationlised “situational crime prevention”,which is:- Target Hardening - reducing criminal opportunities by making thesituation 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 andpolice in preventing fan violence. However, there are design crossovers e.g. Target Hardening,Natural Surveillance and Environmental Management.
  9. 9. Criminal OpportunityLocation, including capableguardianshipVulnerable TargetMotivated offender“Individual criminal events must be understood as confluences of offenders, victimsor criminal targets and laws in a specific settings at particular times and places“.Brantingham and Brantingham, Environmental Criminology (1981)
  10. 10. The Nature of Crime Targets - CRAVED goodsBased on Ron Clarke‟s concept of „Hot Products‟ – those atheightened 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. 11. Some Realities on Offending Behaviours CPTED measures (many rely on psychological cues) may not bethat 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 fullunderstanding of the micro, meso and macro-crime patterns ispointless – well at least the micro-crime patterns Displacement in space, time and target Fear of crime and recitations of pre-conceived ideas i.e. toomuch emphasis on „broken windows‟ as a signal of societalfailure
  12. 12. CPTED PrinciplesTerritorialityNatural SurveillanceAccess ControlTarget HardeningImage MaintenanceActivity Support
  13. 13. Good Practice Planning obligations – e.g. Crime prevention and theassessment of development applications under section 79C ofthe NSW Environmental Planning and Assessment Act 1979 Architect engagement – the US has reached out to AIA and inthe 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 researchedsuccess
  14. 14. Bad Practice Overstating CPTED Effectiveness – e.g. CCTV or lightingeffectiveness often overplayed Unhelpful affiliation with design – making the CPTED fit thedesign and genuinely independent advice could conflict withcommercial 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 berecorded it will develop knowledge
  15. 15. Territoriality
  16. 16. Territoriality Explained Unambiguously define edges between the various types ofspaces 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 privateones Lay claim to semi-public spaces by encouraging residents to usethem.
  17. 17. Natural Surveillance
  18. 18. Access Control
  19. 19. Target Hardening
  20. 20. Image Maintenance
  21. 21. Activity Support
  22. 22. Think Offender and Nuisance in the Space
  23. 23. Does CPTED Work? Cozens found it to be a qualified yes- CPTED components of surveillance, access control, territorialreinforcement, activity support, image/ management, target hardening allindividually contribute to reducing crime & fear in broad range of studies- CPTED shown to reduce crime and the fear of crime in numerousevaluations and to increase property values and investment in the area However:- Support for the effectiveness of comprehensive CPTED projects has notbeen unequivocally demonstrated- Uncertain precisely how CPTED and its component parts work, where itworks best and how to systematically evaluate its effectiveness (orotherwise) beyond reasonable doubt- Rigorous testing and evaluation procedure to produce deeper understandingof theoretical basis of CPTED mechanisms- Uncertain precisely how CPTED and its component parts work, where itworks best and how to systematically evaluate its genuine effectiveness
  24. 24. CPTED and Problems It is prone to fashion and drift of meaning, and meaning differentthings 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 territorialitymay not be universal- The theory has not been integrated – the four strands (Defensible Space,CPTED, Situational Crime Prevention, Environmental Criminology) aresimply placed side-by-side, requiring the user to fit them all together. Thisis inappropriate complexity masquerading as simplicity- Evidence base needs developing on detailed risks of crime addressed byCPTED, causes/ consequences/ interventions
  25. 25. Alternative Practices Accommodating behaviours thatmight be acceptable More space-user CPTED tuning Landscape manipulations Second generation CPTED
  26. 26. Think Design-based Solutions Promote acceptable behavioursand space use Test solution even as a desk-topmulti-disciplinary exercise Think sustainability,maintainability and aesthetics
  27. 27. Think Fear of Crime“Gradually fear extends its domain in the city, with apreference for open spaces. Rarely does it retreat fromconquered ground, and in exchange it takes new ones to addto its domains. It is we who retreat, we who give way, weabandon a space which is left at the mercy of fear.Sometimes we resist, we fight back, we suffer the anxietyrather than lose a space that is ours, though in the end wewill give the position up, we will not set foot in that part ofthe park again after dark, we will avoid thoseneighbourhoods, we will not walk so carelessly in outlyingareas, we will take a taxi instead of the underground after acertain hour”.Isaac Rosa (2008). El país del miedo
  28. 28. 28The Arup ApproachArchitects Client/users DevelopersEarly Engagement (risk-led) by Security Consultants
  29. 29. 29We Should use CPTED to: Reduce the probability of crime and nuisance, whilst enhancingthe 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 fromindividual buildings and interiors to wider landscapes,neighbourhoods & cities Produce designs that are fit for purpose„, and contextuallyappropriate in all other respects Whilst achieving a balance between: the efficiency of avoiding crime problems before construction and the adaptability of tackling them through subsequentmanagement and maintenance To compliment our sustainable approach to projects.
  30. 30. Sources – not an exhaustive list Academic – Clarke, Cozens, Ekblom, Jeffery etc- Theoretical Background to CPTED and Situational Prevention, Ronald VClarke, 1989- Crime prevention through environmental design: a review and modernbibliography Paul M Cozens, 2005. Government:- US – State CPTED networks- Canada – Province CPTED networks- Australia – State and territory guidance (Victoria, NSW and WesternAustralia)- EU – European Crime Prevention Network (EUCPN)- UK – The ACPO Secured by Design scheme Associations and Conference proceedings – These need to belooked at or listened to only by the hardiest, as often there iscritique that may be hard to put in context
  31. 31. Chris Tomlinsonchris.tomlinson@arup.comAny Questions?