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Predicting and Preventing (near) repeat victimisation Professor Shane D Johnson UCL Department of Security and Crime Science [email protected]

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Presentación: forecasting&evidence base el 23 de abril de 2014 en la Primera Cumbre de Análisis Criminal Científico.

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Predicting and Preventing (near) repeat victimisation

Professor Shane D Johnson

UCL Department of Security and Crime Science [email protected]

Overview

•  What do we know about the prevention of repeat victimization and policing hotspots?

•  Enhancing predictions

•  Near repeat reduction strategy example

Repeat Victimisation (RV) Strategies Systematic Review

•  The predictability of patterns of repeat victimisation suggests that “targeting repeat victimization provides a means of allocating crime prevention resources in an efficient and informed manner.” (Grove et al., 2012)

•  Previous reviews have been descriptive or employed vote counting

•  Systematic reviews –  Replicable, transparent review of the evidence –  Meta-analysis reduces Type II statistical error –  Campbell, What Works Centre for Crime Reduction

Grove, L., Farrell, G., Farrington, D.F., and Johnson, S.D. (2012). Preventing Repeat Victimization: A Systematic Review. bra Swedish National Council for Crime Prevention.

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What Works Package Structure

Map of existing Systematic Reviews

Rating and ranking criteria

Guidance on costing interventions and their effects

Searchable database of rated and ranked systematic reviews

12 new mixed method systematic reviews

Design police development programme on evidence appraisal

Primary research

Pilot police development programme on evidence appraisal

Assessing the impact of the WWCCR

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“The proper agenda for the next generation of treatment effectiveness research, for both primary and meta-analytic studies, is investigation into which treatment variants are most effective, the mediating causal processes through which they work, …..”

(Lipsey and Wilson, 1993)

RV Strategies Systematic Review Boolean search terms

•  Key search terms and combinations thereof were used to identify studies within each of >12 databases (e.g. PsychINFO, UK Home Office, Criminal Justice Abstracts) as follows:

(repeat** victim*******) or (multi*** victim*******) or (recidivist victim) or (repeat** burglary) or (repeat** sexual**) or (repeat**racial**) or (poly victim*******) or (repeat** target**) or (prior target**) or (multi*** target**) or (recur**** target**) or (recur**** victim*******) or (multi*** burglary) or (multi*** sexual**) or (multi*** racial**)

Grove, L., Farrell, G., Farrington, D.F., and Johnson, S.D. (2012). Preventing Repeat Victimization: A Systematic Review. bra Swedish National Council for Crime Prevention.

Inclusion Criteria

1. Data had to be available for a period before, during or after intervention. 2. A comparison group was required.

3. A focus on repeat victimization on an individual level rather than a hot spot/area basis had to form a significant part of the study.

Grove, L., Farrell, G., Farrington, D.F., and Johnson, S.D. (2012). Preventing Repeat Victimization: A Systematic Review. bra Swedish National Council for Crime Prevention.

Repeat Victimisation Strategies Systematic Review

Grove, L., Farrell, G., Farrington, D.F., and Johnson, S.D. (2012). Preventing Repeat Victimization: A Systematic Review. bra Swedish National Council for Crime Prevention.

Types of strategies

Residential (19) and commercial burglary (3) •  Target hardening of households •  Property marking •  Neighbourhood or cocoon watch

Sexual victimization prevention (4) •  Education programmes

Domestic violence (1) •  Personal safety plan, some duress alarms and police patrols

Grove, L., Farrell, G., Farrington, D.F., and Johnson, S.D. (2012). Preventing Repeat Victimization: A Systematic Review. bra Swedish National Council for Crime Prevention.

Effect sizes - Odds Ratio

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Pre- Intervention Post-Intervention Action Area a b Control Area c d

Meta-Analysis

Implementation Success

Do geographically focused policing initiatives reduce but displace crime? A Systematic Review

•  Hotspots policing experiments (e.g. Sherman et al., 1989) suggest that geographically focused police patrols reduce crime.

•  What does the weight of the evidence suggest? (see also Braga et al., 2012)

•  What about crime displacement?

Background

•  Dispositional theories predict displacement

•  Earlier research suggested that crime displacement is rarely total

•  At the other end of the displacement continuum is the possibility of a diffusion of crime control benefits

•  Two (or more) mechanisms for diffusion (Clarke and Weisburd, 1994):

–  Deterrence - a carryover effect; offenders perceive that there is an elevated risk of detection and arrest

–  Discouragement – offenders perceive that the effort exceeds anticipated rewards

•  Incapacitation

•  Easy to assume a homogenous group of motivated offenders

The need for a review

•  Literature Reviews: –  Barr and Pease, 1990; Eck, 1993; and Hesseling, 1994 –  Vote counting not meta-analysis

•  No systematic review of diffusion of benefit (Weisburd et al., 2006) –  Bias in favour of looking for displacement

Bowers, K, Johnson, S.D., Guerette, R.T., Summers, L. and Poynton, S. (2011). Spatial Displacement and Diffusion of Benefits Among Geographically Focused Policing Initiatives: A Meta-Analytical Review. Journal of Experimental Criminology. 7(4), 347-374.

Study inclusion criteria

•  Study must evaluate a focused policing intervention (e.g. hotspot policing/ directed patrol, police crackdown)

•  Quantitative measure of crime pre- and post-intervention (for both the ‘treatment’ ‘catchment’ and ‘control’ areas).

•  Published and grey literature

•  Systematic search of databases and relevant articles, hand searches of journals etc

Boolean Search Term (displac* OR “diffusion of benefit” OR “diffusion of benefits” OR “multiplier

effect” OR “free side benefit” OR “ halo effect” OR “spill over*” OR “free rider effect” OR “bonus effect” OR “spill-over”)

AND (police OR policing OR law enforcement) AND (“hot spot policing” OR ‘hot spots policing” OR crackdown* OR “problem

oriented policing” OR “problem solving” OR “focused policing” OR “targeted policing” OR “directed patrol” OR “enforcement swamping” OR “intelligence led policing” OR “broken windows” OR “compstat” OR “community policing”)

AND (evaluat* OR impact OR assessment OR test)

Hierarchy of Evidence

All effect sizes (N=52, 15 studies)

Odds Ratio

Weighted Mean OR (RDM effects)Allatt1984 (Pre-Dur, Catch 1)Allatt1984 (Pre-Dur, Catch 2)

Allatt1984 (Pre-Post, Catch 1)Allatt1984 (Pre-Post, Catch 2)

Braga 1999 (CFS)Braga 1999 (Crime)Braga&Bond2008

Cummings2006 (Treatment 1)Cummings2006 (Treatment 2)

Esbensen1987 (All Crime)Esbensen1987 (Disorder)

Esbensen1987 (Index Crimes)FarrellEtAl1998 (Pre-During)

FarrellEtAl1998 (Pre-Post)Grogger2002 (No Catchment Ctrl)

Grogger2002 (Catchment Ctrl)Higgins&Coldren2000

MazerollePriceEtAl2000McGarrellEtAl2001

Press1971 (Assault, Inside)Press1971 (Robbery, Inside)

Press1971(Assaults, Outside)Press1971(Auto theft, Inside)

Press1971(Auto Theft, Outside)Press1971(Burglary, Inside)

Press1971(Burglary, Outside)Press1971(G Larceny, Inside)

Press1971(G Larceny, Outside)Press1971(Misdemeanors, Inside)

Press1971(Misdemeanors, Outside)Press1971(Other Felony, Inside)

Press1971(Other Larceny, Outside)Press1971(Other Misdemeanors, Inside)

Press1971(Other Misdemeanors, Outside)Press1971(Robbery, Outside)

Press1971(Total Felonies, Inside)Press1971(Total Larc, Outside)

Press1971(Total Misdemeanors, Inside)Press1971(Total misdemeanors, Outside)

Segrave&Collins2005 (Dis, Catch 1)Segrave&Collins2005 (Dis, Catch 2)Segrave&Collins2005 (Dis, Catch 3)

Segrave&Collins2005 (Prop, Catch 1)Segrave&Collins2005 (Prop, Catch 2)Segrave&Collins2005 (Viol, Catch 1)Segrave&Collins2005 (Viol, Catch 2)Segrave&Collins2005 (Viol, catch 3)

Segrave&Collins2005(Prop, Catch 3)Sherman&Rogan1995 (Catch 1)Sherman&Rogan1995 (Catch 2)

Wagers2007Weisburd&Green1995

0 1 2 3 4 5

TreatmentCatchment

-2 -1 0 1 2 3 4

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Treatment Odds Ratio

Cat

chm

ent O

dds

Rat

io Reduction in both areas

Reduction in TreatmentIncrease in Catchment

Increase in TreatmentDecrease in Catchment

Increase in both areas

Monte Carlo (re)samples from all Permutations

Summary of results

Conclusions so far •  Repeat burglary victimisation strategies reduce crime

–  Dosage is important –  Little known about the prevention of near repeats

•  On average geographically focused policing initiatives (for which data were available) are:

–  associated with significant reductions in crime and disorder

–  overall, changes in catchment areas are non-significant but there is a trend in favor of a diffusion of benefit (particularly for RCTs and where there are treatment effects)

•  Understanding where benefits diffuse can help inform where resources can be moved from and to

Predicting future patterns

•  Hotspots research assumes a regularity in spatial crime patterns, with variation by time of day

•  RV and NRV research suggests a regularity in the space-time distribution of risk, with variation by time of day –  Optimal foraging patterns

Bowers,  K.J.,  Johnson,  S.D.,  and  Pease,  K.  (2004).  Prospec:ve  Hot-­‐spo?ng:  The  Future  of  Crime  Mapping?  The  Bri$sh  J.  of  Criminology,  44,  641-­‐658.    

High  

Low  

Risk  

Forecas,ng  -­‐  ProMap  

Bowers,  K.J.,  Johnson,  S.D.,  and  Pease,  K.  (2004).  Prospec:ve  Hot-­‐spo?ng:  The  Future  of  Crime  Mapping?  The  Bri$sh  J.  of  Criminology,  44,  641-­‐658.    

Prediction - basic approach

Grid (50m cells)

Spatial Buffers

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Forecasting (static and dynamic factors) (7- day forecast)

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ProMap

Percentage of area

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ProMap*Roads*Homes

Percentage of area

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KDE

Percentage of area

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Thematic (Hhold rates)

Percentage of area

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Johnson, S.D., Bowers, K.J., Birks, D. and Pease, K. (2009). Predictive Mapping of Crime by ProMap: Accuracy, Units of Analysis and the Environmental Backcloth, Weisburd, D. , W. Bernasco and G. Bruinsma (Eds) Putting Crime in its Place: Units of Analysis in Spatial Crime Research, New York: Springer.

Bowers, K. J., Johnson, S. D., & Pease, K. (2004). Prospective Hot-Spotting The Future of Crime Mapping?. British Journal of Criminology, 44(5), 641-658.

Repeat  Vic,misa,on  –  Road  to  Reduc,on    

Disrup,ng  the  Op,mal  Forager  Predic,ve  Mapping  &  Super  Cocooning  

Trafford – Tackling Burglary Dwelling

Inspector Vincent Jones ,Greater Manchester Police Matthew Fielding, Greater Manchester Police

“In  domes$c  burglary,  for  example,  the  danger  of  a  further  crime  is  greatest  at  the  home  of  the  original  vic$m  and  spreads  out  to  some  400  metres,  but  disappears  over  six  weeks  to  two  months  …  instead  of  mapping  past  events  in  the  conven$onal  way  we  should  map  the  risk  they  generate  for  nearby  homes,  with  the  map  being  dynamic  to  reflect  how  the  risk  declines  over  <me.”    

0000-0100

0100-0200

0200-0300

0300-0400

0400-0500

0500-0600

0600-0700

0700-0800

0800-0900

0900-1000

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0.00-0.20 0.20-0.40 0.40-0.60 0.60-0.80 0.80-1.00 1.00-1.20

Every day 00:00-04:00, Particularly 02:00-03:00 Also 16:00-19:00 Friday and Monday

Original Theory vs Output

Intervention

•  Shift-specific maps each Wednesday to Neighbourhood inspectors (previous patrol plans often at officer discretion)

•  Increasing guardianship –  Neighbourhood police team patrol plans (PCSOs door to door –

inform, reassure, advise, gather intelligence) –  Council community safety patrols patrol areas –  Fire service –  Police driving school

   

§   Average  of  48%  decrease  in  the  target  areas  of  Orange  and  Red  (373  to  194  BDW)  

Results

BDW Count Orange Red Yellow Blue Outside Total 2009/10 139 234 218 159 479 1229 2010/11 66 128 141 97 470 902

Change -52.5% -45.3% -35.6% -38.8% -1.9% -26.6%

12  month  review  –  •   Trafford  saw  902  burglaries,  2nd  lowest  count  across  GMP    •   YTD  2009,  Trafford  saw  a  significant  26.6%  decrease  (1229  to  902  BDW)  (GMP  –  9.8%,  MSG  BCU  GMP  saw  an  increase  of  7%)    

Fielding, M., and Jones, V. (2012). ‘Disrupting the optimal forager’: predictive risk mapping and domestic burglary reduction in Trafford, Greater Manchester. International Journal of Police Science & Management, 14(1), 30-41.

Results

Fielding, M., and Jones, V. (2012). ‘Disrupting the optimal forager’: predictive risk mapping and domestic burglary reduction in Trafford, Greater Manchester. International Journal of Police Science & Management, 14(1), 30-41.

Enhancements •   Tac<cal  Interven<ons:    ‘Super  Cocooning’  –  within  a  manageable  area  (24-­‐48  hrs)  

       Target  hardening  –  via  both  Police  and  Partnership  Resources  (24  hrs)  

•  Extension to theft from vehicles – 29% reduction

Final thoughts

•  Replication in West Yorkshire (48% reduction)

•  Notification of Community Crime (NOCC) intervention to increase community empowerment in Edmonton, Canada (66% reduction in burglary in 6 months)

•  Implementation fidelity (timing and dosage) and accountability

•  More evaluations of near repeat strategies needed

Resources

•  JDi Briefs (http://www.ucl.ac.uk/jdibrief/analysis)

•  POP guide (http://www.popcenter.org/tools/repeat_victimization/)

•  Risk Terrain Modelling (http://www.rutgerscps.org/rtm/)

•  Near Repeat Calculator (http://www.temple.edu/cj/misc/nr/)