Recent Advances in Evidence-Based Policing Around the World: 2015 Lawrence W. Sherman Heather Strang Cambridge University

Research is not enough: pushing research into practice

Three Kinds of Advances in 2015 Advancing the evidence base --Offenders --Places --Victims Advancing Police Agency Uses of Evidence Durham, W. Australia, Uruguay, Trinidad & Tobago, Advancing Governmental Use of Evidence

Triple-T Against Crime & Harm L.W. Sherman Crime & Justice 42 (2015) Evidence-Based Policing Targeting Testing Tracking

TED Map: Evidence-Based Policing Targeting Testing Tracking Power Few Sample Measure Prediction Comparison Feed Back Triage Integrity Correction

Tracking Patrol in Murder Spots 2014

Big Picture of Policing: West Mids

Feed Back COMPSTAT (New York) Cop-Stat (Trinidad)

Implementation If Feed Back does not work, Apply corrections --Ride along at night --Change leaders --Incentives --Discipline SSP David Abraham

How Much Patrol Dosage is Enough? Most hot spots RCTs do not even measure it in Experimental areas. Let alone in control areas No check on integrity Even bigger a problem for police ops than for research Trinidad & Tobago now monitors dosage like a hospital

Trinidad & Tobago TARGETING Pioneers use of GPS For geo-fencing 230 homicide hot spots for more patrol, stops TESTING Uses RCT to estimate effects on murder, guns TRACKING Pioneers weekly feedback to drive up patrols, drive down murder Stephen Williams, MSt Commissioner of Police

Logic of RCT Before: 71 murder/shootings EXP 71 murder/shooting Control During 56 murder/shootings EXP 95 murder/shooting Control EXPECT 95; RESULT 56; 95-56 = 39 prevented 41% Less than Control

Trinidad Randomized Trial

T-20 vs. Control-20 2012-2013

20 Pairs of Stations—Hot Spots or Not

SEBP Special Issue Vol. 25, No. 1 March 2015 Evidence-Based Policing: From Academics to Professionals Sherman & Murray, guest editors http://icj.sagepub.com/content/25/1.toc

1. Targeting Evidence for Policing What Works, What Doesn’t Offenders Places Victims Philadelphia Guns Suffolk DV Visits (Dyads) Turning Point HMOs Hants DV (CARA) E-Tag IOM CT & Trust

Inside Hot Spots—and Out Policing Offenders What’s New? Inside Hot Spots—and Out

3d Philadelphia Hot Spots RCT Temple University 81 Hot “Spots” (22 football fields) 3 groups, block RCT 20 Experimental, 7 control --POP (20+7) --Patrol (20 + 7) --Offender Focus (20 +7) Elizabeth Groff Jerry Ratcliffe

What is “Offender Contact. ” E. Groff, J What is “Offender Contact?” E. Groff, J. Ratcliffe et al CRIMINOLOGY 2015 Philadelphia officers made frequent contact with prolific offenders identified by INTELLIGENCE units, from making small talk with a known offender to serving arrest warrants for a recently committed offense. The most frequent tactic used was surveillance followed by “aggressive patrol” and the formation of INTELLIGENCE partnerships with beat officers; some districts used flat-screen televisions in their roll-call rooms to display photos and convey other intelligence gathered on these prolific offenders to all district personnel. (the future: I-Phone ICT app for facial-recognition?)

50% Reduction in Serious Violence Rates in “Hot Spots” 20 Offender-Focus (O.F.) Hot Spots, 7 controls, 12 weeks More Patrol, POP: NO REDUCTION NOT NUMBERS of CONTACTS: equal frequency MORE TARGETED: who was stopped? More LEGITIMATE? Only known bad guys NOT indiscriminate stopping NO Displacement surrounding areas

Transparency in Journals? Complex statistical analyses No raw numbers of crimes Unfamiliar tests No way to explain except “half as much”

Turning Point Project: Offender-Desistance Policing Peter Neyroud Jamie Hobday Molly Slothower Et al Deferred Prosecution Offer to have NO record As carrot for compliance with immediate treatment Prosecution a 6-month wait

Operation ‘Turning Point’ Sample: offenders whom the police have decided to prosecute, who are: Low risk offenders Who have no previous conviction (they may have previous cautions or other diversions) or one prior conviction (more than 5 years ago if an adult and 2 years ago if juvenile). And offence is not likely to result in instant prison sentence Randomly assigning them to prosecution or police offender management Developing and testing a standard protocol of tactics for police offender management

The Turning Point Experiment Sample of 400 offenders whom the police have decided to prosecute Random assignment=400 Prosecution = 200 Turning Point =200 Comparing like with like: Measure Which has less crime? Cost?, victim satisfaction

Crime Types—Turning Point

Control: court results

Control v Treatment initial failures rates Court non-appearance 25% Turning Point breach rates 25% v

Evaluating Turning Point? If TPP can achieve same results or better At lower cost With no risk of increased harm Police have evidence for deciding not to prosecute Manage volume with legitimacy But only if Victims Believe in It

Birmingham Turning Point Hypotheses: Drawing on past research: Victims will be happy with out of court disposals as long as they feel the police respect them, care about them, and are doing something in their interest How police explain the outcome will matter: reducing reoffending as a legitimate police goal Molly Slothower

Sample 142 Victims of cases randomly assigned to proesecution or Turning Point over a 6-month period 70% response rate in both TPP and prosecution Both conditions explained TPP description emphasized prevention, rehabilitation

“Satisfied” or “Very Satisfied” 46% increase for TPP

The Big Difference? Turning Point sample was more likely to think what happened in their case is going to stop the offender from doing it again. …effect was not likely without attention to communication

Percent Victims Satisfied With Decision

Electronic Tagging in Hants. Paul Bartolomeo Successful experiment Voluntary Tagging Offenders after short prison Would not use Could not use Falsified Proof of Concept Useful Knowledge!

Places: Targeting & Testing Harm Spots: Cristobal Weinborn Illegitimacy Hot Spots: Alex Murray

Targeting Hot Spots: Crime, Harm, Demand Counts of crime At same units of analysis Whether addresses, intersections, street segments Regardless of crime types selected All crimes are created equal? Showing probability of encountering any crime of that type (or types)

Why Crime COUNTS? Are all crimes created equal? Aren’t some more serious than others? Does the prescribed sentence length indicate it? Canada—Crime Severity Index (2009) Cambridge Crime Harm Index (2007)

Defining “Harm” Spots Prescribed penalties for crimes Common currency of days in prison Sentencing Guidelines, Any state; or a national average Each AND ALL crime types In each unit of analysis In the following graphics, Unit of analysis = street segments One street from one intersection to the next

Hot Spots of Birmingham--counts

CHI “Harm Spots”—same scale

What’s The Difference? Hot Spots are less concentrated than harm spots—they cover more area of land Harm spots are taller than hot spots More of the harm in Birmingham is concentrated into less land than the same percentage of crime counts Police can target fewer places, less space, with for more harm reduction using harm spots than by using hot spots.

Hot vs. Harm Spots

Inside Hot Spots: Special SEBP Issue of ICJR article Slough Non-domestic indoor violence Houses of Multiple Occupation Simon Bowden, Thames Valley Violent crime 137 times higher in HMOs Than in non-HMO dwellings Most HMOs illegal

Hot Spots of Illegitimacy: CT Humint and Survey Data

How can police target with information already collected on DV ? Best evidence to date: Suffolk UK (pop.730k). Matthew Bland, Crime Analyst Cambridge Mst thesis—brilliant job! Analysis of 36,000 DV police callouts between 2009 and 2014. Matthew Bland

Many and few callout cases Most dyads (76%) had only 1 report in 5 years BUT they had 54% of all harm, i.e. police have no priors recorded for over half of cases involving harm—and no subsequents

Crime Harm Index (CHI) Number of days imprisonment by offence type Multiply Number of offences X days in jail Not actual, but sentencing guideline Social judgement of seriousness of crime

‘Power few’ findings Half of all repeat offenders offended against multiple victims 30% of all repeat victims were victimised by more than one offender 80% of all CHI harm occurred in < 2% of all dyads (412 of 24K cases) Over half (53%) of the cases contributing to this 80% had just one reported event.

Volume of Domestic Violence Couples by Serious Harm (Sentencing Guideline Prison Days if Convicted) Highest Harm 2% of Dyads Medium Harm 18% Of dyads Low Harm 80% of dyads

Does offence seriousness escalate over time? Most dyads show no escalation in CHI harm The tiny fraction who reach four callouts do show a sharp escalation in seriousness.

What we can learn about Targeting Domestic Violence: Differentiate levels of harm Look for a “power few” that drive the total harm levels Target police resource allocation to do the most good with limited tools and time

Broader lessons: Stop treating DV as a ‘unitary’ phenomenon Recognise that: it covers a wide range of seriousness; some victims are repeatedly victimised; some offenders offend against multiple victims. Remembering that police can only act on reported incidents, we cannot assume these are the only incidents: multi-agency approaches needed to identify “hidden” cases before first, high-harm events? Think about ‘segmenting’ DV so that different policies and interventions can be applied for different kinds of case

Evidence-Based Policing of Domestic Abuse 2015 Heather Strang Cambridge University

Targeting Domestic Abuse A story about segmenting complex behaviour - Differentiating levels of harm What works for whom?

Domestic Violence Couples by Crime Harm Index (Sentencing Guideline Prison Days ) Bland, 2015 80% Total CHI Days Highest Harm 2% of Dyads Medium Harm 18% Of dyads Low Harm 80% of dyads

Testing Police Responses to DA Southampton CARA Project (Hants) – Low harm, high volume Bracknell Forest (Thames Valley) – Medium harm, repeat offending Merseyside – High harm, repeat offending

Southampton, Hampshire: ‘CARA’ conditional cautioning program Target is low-serious incidents (and strict CPS evidence test) Adult male offenders who admit the offence No violence preceding 2 years Spousal incidents only Victim indicates no safety risk through this disposal

Random Assignment: Two Types of Caution Good Behaviour Only 4 months No more Domestic Abuse Then no prosecution Criminal Record shows caution Conditional Caution/ Workshops Held in a hotel by Hampton Trust Two Sessions 3 weeks apart Saturday mornings 3 hours each All-male group Discuss domestic abuse issues ‘Motivational’ techniques e.g. What would your kids say? Not directive Encourage understanding DA Final session: set a goal for DA

Partnership Effort Cambridge Heather Strang Lawrence Sherman Barak Ariel HAMPSHIRE POLICE Alex Marshall Robin Jarman Scott Chilton Jo Rowland Nicky Cornelius Rob Braddock Tony Rowlinson

Data So Far UK’s Longest-Running Police Experiment? 137 weeks and still randomizing cases 256 cases randomised to date via Cambridge ‘Randomiser 185 cases have at least 12 months reoffending data 96 Controls (Conditional Caution alone) 89 CARA cases (CC + Hampton Trust Workshop)

X2=3.131; p=.077 54% Reduction (20/96) (10/89)

X2=4.342; p=.037 40% reduction (16/96) (6/89)

X2=1.789; p=.181 (6/96) (2/89)

X2=0.646; p=.421 (7/96) (4/89)

54% Fewer charges in DV Workshop Group (P = .028; Poisson distribution)

72% Fewer Non DV charges in DV Workshop Group (P = 72% Fewer Non DV charges in DV Workshop Group (P = .006; Poisson distribution)

29% Fewer DV arrests in DV Workshop Group (P = 29% Fewer DV arrests in DV Workshop Group (P = .294; Poisson distribution)

64% Fewer Non_DV arrests in DV Workshop Group (P = 64% Fewer Non_DV arrests in DV Workshop Group (P = .091; Poisson distribution)

Promising but for Whom? To get the 256 cases so far randomly assigned, 5562 cases assessed for eligibility so far. In catchment area between 25 and 40 DA cases each week About 50% are charged and about 50% NFA. Caseflow averaging 1.86 cases per week. What needs to happen to get more non-charged cases? – and not just in Hampshire.

Bracknell TVP DA Experiment Multi-agency services for both victims and offenders, but separately. Eligibility based on risk and frequency of calls – the most persistent cases. At least 6 months post-RA reoffending data now available.

Bracknell Results so far: Raw count of repeats similar for E and C but Major reduction in serious harm in E group after treatment but More harm in E group during treatment - mainly more RO breaches – treatment effect? Results so far ambiguous but promising – Need more cases and more follow-up time.

Merseyside Police Experiment: Chronic Offenders Police rank-ordered persistent DV offenders by frequency in callouts Selected ‘top 200’ offenders Randomly assigned 100 to experimental treatment: Police contact them, preferably face to face Inform them they are under close surveillance: any offence will be charged Close contact and monitoring of victims by DV women’s support group Outcome measure will be comparative DV reoffending

What Works For Whom? Different Effects on Different People Different N of priors Different Harm Levels

Totally-Evidenced Policing British Transport Police EBP, Analysts Trained Western Australia Police—EBPU, 100 trained Durham Police—EBPU Trinidad & Tobago—500 trained out of 6,000 Uruguay Police—300 trained

Governmental Use of EBP 2015 Professor Laurie Robinson, George Mason U.

Legitimacy, Procedural Justice, and Police Body-Cams Dr. Barak Ariel

Lawrence W. Sherman Heather Strang Cambridge University THANK YOU! Lawrence W. Sherman Heather Strang Cambridge University