pnodp - University of Cambridge

Offender Desistance Policing? Presentation for the 4th International Evidence Based Policing Conference

Peter Neyroud CBE QPM University of Cambridge

Overview • An outline of the theory • Turning theory into practice: a programme of experiments • The implications for practice

Context • Pressure on criminal justice budgets • Renewed emphasis on prevention and rehabilitation

Life course criminology • Growing understanding from key work such as the prizewinners, Sampson and Laub • Desistance as a process with turning points • Opportunities to focus on encouraging desistance amongst the known offenders • Particularly the “power few” who are persistent • But also to prevent others joining them

Crime Harm Forecasting • Since Meehl 1954 Clinical Versus Statistical Prediction • Statistical Prediction beats Clinical • Most contests before statistical learning • Cheap supercomputers • “Data mining” that assays every possible pattern of precursors • Identifies best prediction combinations

New Generation of Risk Forecasting • Based only on Prior Charges, Residence, Age, Sex—no PSR • Nothing qualitative • More like a short-term weather forecast • Based on huge samples • E.g., 30,000 in Philadelphia • Journal Royal Statistical Society, Series A, 2009

Richard Berk

Geoffrey Barnes (2007) 2-Year Berk Forecast Test, Philadelphia APPD Cases High Risk (2%) Neither High nor Low Risk (38%)

Low Risk (60%)

Effects of Prosecution and Prison on recidivism • “almost all of the results are negative in direction, as measured by prevalence, incidence, severity, and selfreport outcomes.” Petrosino et al. (2010) • “Growing research evidence suggests that for many if not most people put in prison for the first time, the net effect of prison may be to cause more crime than if the sentence had not been custodial” Sherman and Neyroud (forthcoming) • The deterrent effects of Prosecution and Incarceration are balanced by potentially negative treatment effects, particularly for first time entrants

Certainty and Celerity not Severity: a cause for HOPE? • Operation HOPE focused on recidivist drug offenders – Emphasis on certainty of punishment if treatment conditions breached – Trial showed a near halving of overall incarceration rate

• HOPE is being replicated in 2 mainland sites and results appear consistent • HOPE appears to be effective with lower risk offenders

Offender Focused policing • Police can replicate many of the preventive effects of HOPE but before prosecution • For example, Restorative Justice experiments (Sherman and Strang) demonstrated positive effects in reducing violent reoffending (less effective with property offenders

The Sword of Damocles • 2 Experiments in Omaha, Nebraska testing different approaches to domestic violence (Dunford et al. 1990). • “These experiments found that the mere issuance of a warrant for an offender’s arrest had a greater deterrent effect than actually arresting the offender” • The more general form of this proposition is that by communicating more certainty that some action will be taken, police may able to prevent many offences from occurring

A Programme of experiments • Stage One: constructing a Crime Harm Index • Stage Two: First Time Offender diversion to offender desistance policing • Stage Three: applying the CHI as a triage tool in police custody suites • Stage Four: testing which tactics produce the best

The Crime Harm Index • A random sample of 100,000 records from the UK Police National Computer’s Phoenix criminal records database • Produces over 3,000,000 data items about the 100,000 offenders • Replicating Berk’s model with the larger database • Using statistical analysis to model the factors predicting serious harm

First Time Offender trial • Taking a sample of offenders whom the police have decided to prosecute • Who have no previous conviction (they may have previous cautions or other diversions) • Randomly assigning them to prosecution or police offender management • Developing a standard protocol of tactics for police offender management linked to “sword of Damocles” approach

A Triage tool for custody officers • From the CHI work with the Police National Computer, developing a triage tool to guide custody decisions about investigation, prosecution and diversion • Applying that tool in a further trial linking police offender management to CHI triage • Measuring the outcome against an index of crime harm

Testing the tactics • In the later trials, testing the relative benefits of different elements of the protocol of tactics against each other • Matching interventions more effectively to offenders • Experimenting with Community, volunteer and other agency support for the tactics

Conclusions • “It is entirely possible that all of these tactics could fail to foster desistance from crime, even though the strategy of diversion or harm-forecasting could work nonetheless. There may be more general validity finding by Petrosino and his colleagues (2010) that doing nothing with juveniles was better than doing something, at least in terms of repeat offending. Yet it is very difficult to reconcile doing nothing with deeply held moral values for holding offenders accountable. Whatever works in terms of helping offenders desist should also be seen as a form of justice, one by which offenders must pay a price.” Sherman and Neyroud, forthcoming