Evaluating Surrey Police's High Harm Perpetrator Unit

Research Institution / Organisation

College of Policing

In Collaboration With

University of Birmingham

Principal Researcher

Wusu Kargbo

Level of Research

Professional / Work-based

Project Start Date

February 2019

Research Context

​This evaluation project is managed by the Vulnerability and Violent Crime Programme, which was set up by the College of Policing from a grant awarded by the Police Transformation Fund. It is one of eight projects overseen by the programme.

In one district under the jurisdiction of Surrey Police, the force has developed an intervention that combines and co-locates their existing Integrated Offender Management (IOM) and Violent and Sex Offender Register (ViSOR) functions. The new ‘High Harm Perpetrator Unit’ (HHPU) deals with serious sex offences, domestic abuse, hate crime, child abuse and serious violent crime and has also developed an algorithm that supports the identification of high harm perpetrators in these areas.

The aim of the intervention is to deliver improved offender management, through development of omnicompetent offender managers (OMs) who are able to efficiently and confidently manage the risks of high harm suspects/offenders.

The research project will evaluate the implementation of the HHPU, and the application of the algorithm to identify cohorts of high harm suspects who would not be traditionally identified through IOM/ViSOR. The evaluation will also explore the range and effectiveness of interventions that are applied to manage offenders.

A cost-benefit analysis will also attempt to identify any economic benefits of the intervention.

Research Methodology

​Interviews and document reviews will yield data to be analysed.

How well the intervention is implemented (creation and running of the HHPU, algorithm and types of intervention applied) will be determined by comparing it with the previous mode of operation (separate IOM and ViSOR units). The evaluation will also explore officer views on issues such as the co-location of functions, knowledge transfer, workload distribution and capacity to process cases, identification of offenders, training, multi-agency working.

At the beginning of the evaluation, offenders identified through the algorithm will be followed for 6 months to see if they commit higher levels of reoffending (compared to similar cases under the previous means of operation). Algorithm results will also be compared against professional judgement and other risk algorithms to see if similar results are produced.

Interim reports and publications

Not available

Date due for completion

July 2021
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