Situational crime prevention Displacement & Diffusion

Situational crime prevention Displacement & Diffusion

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Review of SCP • 5 technique categories

– Increase effort – Increase risk – Reduce rewards – Reduce provocations – Remove excuses

• Opportunity is key theoretical assumption of SCP – Opportunity plays a role in causing all crime

• Crime opportunities (CO) are highly specific • COs are concentrated in time/place • COs depend on everyday movements, routines • Some products offer more tempting COs • Social changes (e.g., technology) produce new COs • COs can be reduced

– Reducing opportunities does not usually displace crime – Focused opportunity reduction can produce wider declines in crime

Displacement of crime? • Claim: SCP does not truly prevent crime b/c motivated

offenders will just change targets – Crime can be displaced by SCP efforts

• “change in crime due to preventative actions” – Displacement shares main assumptions of opportunity theories

• Offenders respond to opportunities to commit crime (risks, reward, effort, provocation, etc.)

• SCP is flawed b/c opportunity is not the only cause of crime – Crime occurs due to root causes in the individual’s development and

environment that create motivation to offend • SCP shifts where motivated offenders find those opportunities

– This isn’t really prevention

Four assumptions of displacement • (1) Offenders make rational choices – Offenders respond to payoff, effort, risks • If offenders did not, SCP would not reduce crime or

cause displacement

• (2) Crime is inelastic – “not responsive to changes in price” • Offenders will not change their behavior just because

crime becomes more “costly” – So increasing risks, reducing rewards, and increasing effort will

not change offender behavior because the motivation to commit crime is independent of situational opportunity

Four assumptions of displacement

• (3) Offenders have mobility – Ability to change time, place, tactic, target, etc. • If offenders do not have this ability, displacement will

not occur – Some offenders may have less mobility than others (e.g., youth) – Also may be natural barriers (highway, river, etc.) that limit

movement among targets

• (4) Alternative targets/choices are available – As long as other criminal opportunities exist, motivated

offenders will find them

Forms of displacement • Territorial displacement

– Change in place

• Temporal displacement • Change in time

• Tactical displacement – Change in methods

• Target displacement – Change in victim

• Functional displacement – Change in crime type

• Perpetrator displacement – Change in offender

Territorial

• Change in crime from one geographical area to a contiguous geographical area – E.g., Neighborhood

watch program causes burglaries to reduce by 50% in neighborhood, but burglaries increase by 30% in contiguous neighborhood

Temporal

• Change in crime from one time to a different time – E.g., Temporal SCP

measures such as a night citizen patrol causes more crime to move to daytime

– E.g., SCP measures aimed at weekend activities shifts crime to weekdays

Tactical • Change in methods

used to commit crime – E.g., Installation of better

door locks causes burglars to force entry through window

– E.g., Tighter gun control measures cause armed robbers to use knives or some other weapon

Target • Change in victim of

crime within same area – E.g., Home alarms cause

burglars to shift from houses w/ alarms to houses w/out alarms

– E.g., Immobilization software in new cars causes car thieves to switch to older cars

Functional

• Offender shifts from committing one type of crime to another – E.g., Making burglary

more difficult through increased home alarms causes offenders to commit more robberies or larcenies in public spaces

Perpetrator

• One offender stops, another offender replaces the first – E.g., Offender stops

dealing drugs in response to increased street lighting, which causes another motivated offender to begin dealing drugs in the same area (given new opportunity)

Malign vs. benign displacement • Malign displacement

– Changes in crime cause more undesirable outcomes • E.g., SCP measures cause decrease in local burglaries (non-violent offense)

– Displacement causes increase in local robberies (violent offense)

• Benign displacement – Changes in crime benefit society

• E.g., SCP measures cause crime to shift from violent theft (e.g., robbery) to non-violent theft (e.g., identity theft)

• Displacement may create “crime fuses” – Areas where crime moves and is allowed to operate without

bothering rest of society • Like a fuse, this can “explode” into an uncontainable situation

Diffusion of benefits • Crime prevention efforts may spread benefits beyond

the targeted people/places/times – Also called “halo effect” or “free bonus effect”

• Can be considered the other side of the coin to displacement

• What would cause diffusion of benefits? – Deterrence

• SCP measures deter offending beyond targeted offense by increasing the perception of risk – E.g., CCTV in one car park cause auto theft to decrease in all car parks in an area

– Discouragement • SCP measures aimed at one crime discourage other crimes by

increasing effort to commit any crimes in an area – E.g., Improving street lighting in an area discourages potential offenders from

looking for other “unlit” areas due to increased effort

Evidence of displacement? • Evaluations often do not measure displacement

– Two studies found little evidence of displacement • Guerette & Bowers (2009) found displacement in 29% of SCP

evaluations in systematic review (n = 102) – Temporal was most common; tactical was least common – Where it occurred, displacement was typically smaller than crime reduction

» I.e., benign displacement • Telep et al. (2014) found that spatial displacement in area-based SCP

interventions was not common – Across 127 coded effect sizes from 43 studies, found displacement of crime in

11.9% of effects » Crime reduced in 46% of outcomes

– A cro ss

• Little reason to expect total displacement of crime – Even if some displacement occurs, net result would be crime

reduction • So displacement is not an inevitable result of SCP, but is possible

and should be considered in evaluations of SCP measures

Evidence of diffusion? • Can be measured by looking at crime reductions

in areas surrounding the target area – But reduction in crime in target and control areas could

indicate unrelated crime reduction in society at large • Another issue is that diffusion effects and displacement effects

could offset, making it hard to detect either

• Diffusion is hard to measure! – Some evaluations have uncovered evidence of diffusion,

similar (but opposite) to evidence of displacement • Guerette & Bowers (2009) found diffusion of benefits in 27% of

SCP evaluations (n = 102) • Telep et al. (2014) found diffusion of benefits in 22.2% of

observed effects

Situational crime prevention (SCP)

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SCP THEORY

Introduction • Of the three major strategies, this targets the

“proximate” causes – Influenced by economic theory (decision-making)

• Focused on how to decrease likelihood of crime event in a given situational context – Any crime prevention measure that is: • directed at highly specific forms of crime • involves management/design/manipulation of immediate

environment • to reduce opportunity for crime or increase the perceived

risks of crime

Theoretical backdrop • Rational choice theory – Increase risks, increase effort, decrease rewards

• Routine activities theory – Harden targets, provide guardians, and decrease

motivation to offend

• Crime pattern theory – Crime is not dispersed randomly in space or time

Rational choice theory • Assumes offenders make choices based on opportunities

– Calculated decision based on risk, effort, and potential reward • Rewards (benefits) > Risks (costs)

• Crime scripts – May not be conscious decision process

• Instead, rely on “behavioral routines” (i.e., habits) that sketch out steps and actions for crime, based on experience

• Qualitative research on burglary offenders present clear evidence of rational choice – Burglars do not choose homes at random, but based on location,

occupancy, lighting, time of day, ease of entrance/exit, etc.

Routine activities theory • Expands idea of crime scripts based on “daily

routines” – Routine activities have changed over time

• E.g., shift to two income homes has produced more empty houses during daytime hours

• Opportunity is cause of most crime – Opportunity = motivated offender + suitable target + absent

guardian • Opportunity is convergence of 3 elements in daily routines

• Lifestyle perspective – Lifestyle of victim and offender create these opportunities

• Is victim motivating/tempting an offender? Is victim a suitable target? Is victim going somewhere without capable guardians?

• If offender being supervised at job, does offender have lots of unstructured time (i.e., “idle hands”)

Crime pattern theory • Crime fits patterns in terms of “where” and “when”

– Not randomly distributed in time and space

• Two keys to understanding patterns: – Environment backcloth (EB)

• “social, economic, cultural, physical conditions within which people operate” – Social/crime template (SC template)

• “people have templates that outline expectations of what will happen at certain times and places . . . the template tells an offender what should occur in a certain place, time, or situation”

– Given EB & a SC template, people form “cognitive maps” • Cognitive maps involve “nodes” of activity and “paths”

– Some nodes are “crime generators” (bring in suitable targets), some are “crime attractors” (bring in motivated offenders), and some are “hunting grounds” (absent guardians)

• Offenders typically search for opportunities within the “nodes” and “paths” with which they are familiar

High-risk targets • Research reveals that crime is highly

concentrated at: –High-risk places –High-risk times –By a small group of high-risk people

• Targeting these places/times/people is sometimes referred to as “hot spots” approach

Situational crime prevention • Original 3 approaches (Clarke, 1983) – Surveillance (increasing risks) – Target hardening (increasing effort) – Environmental management (reducing rewards)

• 5 typologies (Smith & Clarke, 2012) – Increasing effort – Increasing risk – Reducing rewards – Reducing provocations – Removing excuses

Increase effort of crime • Harden targets – E.g., steering locks, car immobilizers, anti-robbery

screens at banks

• Control access – E.g., apartment entry phones, subway turnstiles,

alley gates, making it difficult to enter areas with children

• Screening exits – E.g., electronic tags, exit tickets, requiring bus

passengers to enter near driver

Increase risk of crime • Extend guardianship – E.g., signs of occupancy, wide aisles in stores to

make theft more visible

• Increase surveillance – E.g., street lighting, neighborhood watch, natural

surveillance through decreased congestion and physical design

• Reduce anonymity – E.g., cab driver IDs, school uniforms

Reduce rewards of crime • Conceal targets – E.g., unmarked armored trucks, off-street

parking

• Remove targets – E.g., removable car radio, women’s shelters

• Identify property – E.g., vehicle licensing, cattle branding

Reduce provocations to crime • Reduce frustration/stress – E.g., soothing music, muted lighting, polite service

• Avoid disputes – E.g., separating sports fans, reduced crowding in

pubs

• Reduce arousal/temptation – E.g., controls on violent pornography, screen

youth workers and prohibit pedophiles from working with children

Remove excuses to commit crime

• Set rules – E.g., rental agreements, harassment codes

• Post instructions – E.g., “no parking,” “private property”

• Alert conscience – E.g., speeding displays, “shoplifting is stealing”

Major criticisms (and responses) • It is simplistic and a-theoretical

– Based on three opportunity theories, as well as social psychology • It diverts attention from the root causes of crime

– By achieving immediate crime reduction, it benefits society • It is a conservative, managerial approach to crime

– It promises no more than it can deliver; solutions must be economic, practical, and socially acceptable

• It promotes a selfish, exclusionary society – It can provide protection for everyone, rich and poor

• It promotes Big Brother and restricts freedom – The democratic process involves a balance of freedom and security; people are willing to

deal with small infringements to freedom to increase safety • It blames the victim

– It empowers victims by providing information about how to avoid crime risks • It doesn’t work, but displaces crime and often makes it worse

– This is an empirical question we can investigate

Limitations to SCP • SCP focuses on situations where crime is likely to

occur, but does not address root causes – I.e., there are probably natural limits to how much SCP

alone can reduce crime since it does not seek to change individuals (DCP) or communities (CCP) • SCP proponents would argue that SCP does not compete

with DCP or CCP – It is a third, complementary strategy

• Displacement of crime? – Does SCP reduce crime, or just cause it to move elsewhere?

• Next week!

CPTED Crime prevention through environmental design

CPTED • Crime prevention through environmental design – “Defensible space”

• Physical characteristics of an area can influence behavior of residents and potential offenders

– Includes: • Territoriality • Natural surveillance • Image • Milieu • Access control • Activity support • Target hardening

Territoriality • Territoriality means that an area is owned – “Sense of ownership over an area which prompts

people to take action when something seems amiss”

• Real vs symbolic – Real territoriality

• “walls, fences, gates, or other items that place a physical barrier in front of people”

– Symbolic territoriality • “things such as signs, landscaping, or other items that

signal a change in ownership area”

Surveillance • Natural (informal) surveillance – “The ability to observe activity, whether inside or

outside, without the aid of special devices”

• Organized (formal) surveillance – Use of guards or employees tasked with watching

over an area

• Mechanical surveillance – Utilizes technology to observe activities (e.g.,

cameras), or lights to enhance natural surveillance

Image & Milieu • Image – “A neighborhood having the appearance that it is not

isolated and is cared for, and that residents will take action”

• Milieu – “The placement of a home, building, or community

in a larger area characterized by low crime”

• Purchasing real estate – E.g., buy up abandoned buildings/lots and build

expensive condominiums or businesses

Access control & target hardening • Access control – “The ability to regulate who comes and goes from

an area or building, with the intent of limiting access to legitimate users” • E.g., gated communities, private roads, cul-de-sacs &

dead-end streets

• Target hardening – “Actions that increase the effort by offenders in

committing a crime” • E.g., locks, gates, strong windows

Activity support • “Functions that assist and enhance

interaction between citizens and other legitimate users in the community” – Building a community atmosphere

• E.g., use of public space by communities (street fairs, community events), designing safe areas for such activities, maintaining community spaces

– Can also include anti-crime community activities • E.g., neighborhood watch, community-wide initiatives to

tackle incivilities or disorder and promote community (prevent social stigma)

SCP PROGRAMS Crime Prevention through Environmental Design (CPTED)

Major approaches to CPTED

• Street lighting • CCTV • Physical design (natural surveillance) • Organized surveillance • Property identification programs • Alarms • Locks, doors, & access factors • Area permeability

Street Lighting • Improved street lighting may decrease crime

in several ways – Increase outdoor activity & natural surveillance – Enhance ability to detect crime in progress and

intervene – Improve ability to identify potential offender

• Lighting is popular because it is inexpensive and creates sense of guardianship in an area – Much crime occurs at night, and offenders often

choose poorly lit areas

Does street lighting prevent crime? • Meta-analysis by Farrington & Welsh (2002)

– 13 evaluations found average 20% reduction in crime (OR = 1.25) • Included studies with an experimental area with lighting and control area without

lighting, before and after lighting (i.e., level-3 quality) • 9/13 studies found significant reduction in crime after street lighting

• UK studies showed stronger effects than US studies – Average effect among 8 US studies was OR = 1.08

• 7.5% reduction – Average effect among 5 UK studies was OR = 1.42

• 29.5% reduction – UK studies (1991–2001) more recent than US studies (1974–1979, 1998)

• Nighttime crime did not decrease more than daytime crime – Might imply that causal mechanism is not surveillance

• One other possibility is that community pride caused street lighting as well as reduction in crime (i.e., selection bias)

Closed circuit television (CCTV) • Mechanical surveillance of an area is most

often accomplished by camera – CCTV has become very popular • Especially in UK where there are 4–6 million public

CCTV cameras – Most are private, not government

• CCTV can be placed in many locations – E.g., public transportation, car parks,

businesses, city centers, and public housing

Does CCTV prevent crime? • Meta-analysis by Piza et al. (2019) (updating Welsh & Farrington [2009])

– 76 evaluations found average 20% reduction in crime (summary OR = 1.14) • Included studies with experimental area with CCTV and control area without it, before and after

– I.e., level-3 quality

• Effects varied by setting – Car parks

• Across 8 evaluations, crime reduced 37% (OR = 1.59) – City/town centers

• Across 33 evaluations, crime did not decrease significantly (OR = 1.07) – Housing complexes

• Across 10 evaluations, crime did not decrease significantly (OR = 1.03) – Residential areas

• Across 16 evaluations, crime reduced 12% (OR = 1.13) – Public transport

• Across 4 evaluations, crime did not decrease significantly (OR = 1.37)

• Effects varied by country – Significant crime reduction in South Korea (OR = 1.51, n = 3) and UK (OR = 1.26, n = 34)

• No significant crime reductions in Canada (n =6 ), Sweden (n = 4), or US (n = 24)

Natural surveillance • Physical design can improve natural surveillance

– Prospect = ability to see an area • Blocked prospect associated with greater fear & victimization

– Refuge = presence or absence of concealment in which potential offenders could hide • Increased refuge associated with greater fear & victimization

– Escape = ability of both offenders and victims to escape from an area • Limited escape associated with greater fear & victimization

• Evaluations indicate several positive effects associated with increased informal surveillance – Reduced burglary, robbery, & theft – Reduced fear

Other CPTED approaches • Organized surveillance

– Security guards in parking lots & public transportation, caretakers in public housing • Evaluations show some positive impact

• Property identification programs – Identifying property may make it more difficult to dispose of stolen items

• Unclear impact

• Alarms – Evaluations show decreased burglaries for homes with alarms

• Interviews with burglary offenders suggest many inspect target homes

• Area permeability – Cul-de-sacs, dead-end streets, and alley gates

• Evaluations suggest reduced crime and reduced fear of crime

• Other access control – Measures such as dead-bolt locks and sliding glass door pins = increased effort

• Unclear impact

Mentoring programs to affect delinquency and associated outcomes of youth at risk: A comprehensive meta-analytic review

Patrick H. Tolan & David B. Henry & Michael S. Schoeny &

Peter Lovegrove & Emily Nichols

# Springer Science+Business Media Dordrecht 2013

Abstract Objectives To conduct a meta-analytic review of selective and indicated mentoring interventions for effects for youth at risk on delinquency and key associated outcomes (aggression, drug use, academic functioning). We also undertook the first systematic evaluation of intervention implementation features and organization and tested for effects of theorized key processes of mentor program effects. Methods Campbell Collaboration review inclusion criteria and procedures were used to search and evaluate the literature. Criteria included a sample defined as at risk for delinquency due to individual behavior such as aggression or conduct problems or environmental characteristics such as residence in a high-crime community. Studies were required to be random assignment or strong quasi-experimental design. Of 163 identified studies published from 1970–2011, 46 met criteria for inclusion. Results Mean effects sizes were significant and positive for each outcome cate- gory (ranging from d=0.11 for academic achievement to d=0.29 for aggression). Heterogeneity in effect sizes was noted for all f