28 July 2021

Vulnerability and Violent Crime Programme: Findings from the serious violence diversion interventions

Evaluations of two interventions designed to reduce serious violence have now been published and here we share some of the main findings.

Supported by funding from the Police Transformation Fund, the College has been working with the NPCC to build the evidence base on vulnerability and violent crime. Focused on mapping and evaluating new and emerging practice, the programme is now publishing a series of reports and through July 2021, has run online seminars to disseminate the findings.

DIVERT is an intervention that at the time of the evaluation was being delivered in six custody suites across the Metropolitan Police Service, where custody is used as a "teachable moment" to divert young people away from crime. Young people (between the ages of 18 and 25) are given the opportunity to meet custody intervention coaches (CICs) for an information and guidance (IAG) meeting. At these meetings CICs engage with young people to understand their main challenges (e.g. employment, education, training, housing, etc.) and offer support and access to services.

The intervention was evaluated using a mixed-methods design. The impact evaluation used police data and DIVERT management information to test whether DIVERT participants were less likely to be re-arrested, and whether the severity of their offending changed, compared to those who did not receive the intervention. The process evaluation involved interviews with providers and participants to explore the experience of delivering the programme and the perceived impact on staff, participants and local communities. Cost analysis data was used to estimate the cost of DIVERT per participant.

The main findings from the evaluation are:

  • In the very short term (up to six months), DIVERT participants were found to be re-arrested at higher rates than those who had not participated in an IAG meeting. In the longer term, re-arrest rates were no different between groups, with the exception of the suite where the intervention had been running for the longest (Brixton), where the evaluation found a positive impact on re-arrest after 12 months. This indicates that in locations where the intervention is well-established and properly implemented, there is a positive impact on rates of re-arrest.

  • There are however issues with the comparison - all we know about those receiving the intervention is that they had a meeting with a CIC, not what happened after; we also don't know if those 'selected in' by coaches are any different (e.g. they have more complex needs) to those who did not receive the intervention.


The Community Initiative to Reduce Violence (CIRV) is delivered by Northamptonshire Police alongside a range of partners. It is open to all ages (but focused on under 18s) and works to divert people involved or at risk of becoming involved with gangs into a range of local support services. The intervention receives referrals from various sources, for example a school, parent or from police or partnership intelligence, and uses a triage process to assess individual needs. Participants are then allocated to specific services or to a CIRV navigator, who works with the participant and supporting agencies to help ensure a consistent and joined up response.

The impact evaluation drew on three sources of quantitative data: Northamptonshire Police's Serious Crime Matrix (SCM), which is used to profile people suspected, or at risk of becoming involved in gang violence or associated crime; monitoring information used by the CIRV team to track young people and adults referred to the programme; and a bespoke survey completed by a sample of programme participants to collect additional information about the profile of young people and adults engaging in CIRV.

The process evaluation included 15 in-depth interviews with CIRV strategic and operational staff and delivery partners. Five interviews were conducted with young people and adults engaged in CIRV ('programme participants') and four with their parents/carers. Interviews focused on participants' views and experiences of CIRV's set-up and delivery, and its perceived impacts and outcomes on the programme participants, their families and local community. There were also observations of key meetings and a 'call in' event run by the intervention.

The cost analysis data was collected from intervention leads and used to estimate the cost of CIRV per participant, averaged over three years to account for higher costs associated with programme setup and rollout.

The main findings from the evaluation are:

  • On average, individuals who had a CIRV navigator made statistically significant improvements on their Outcome Star/ Youth Outcome Star scores (which assess individuals on areas such as housing, health, mental health, life skills and relationships).

  • Overall indicative evidence from quantitative analysis suggests a positive change occurred for individuals who engaged with CIRV navigators, however these findings have not been compared to a control group who did not receive the intervention.

  • Findings from in-depth interviews highlighted that operational and strategic staff, programme participants and their families perceived CIRV to be a success. They felt CIRV had helped reduce offending behaviour and involvement in gangs, changed the direction of individuals' lives who were involved in criminal activity and positively changed their perceptions of the police and support services.


Both evaluations have implications for practice and implementing multi agency approaches to reducing serious violence. Future research using longer term data would help us to understand better the overall impact of the interventions.

The full reports and accompanying summaries are available for download at the bottom of the page.

To access the reports for the other interventions which were evaluated as part of the VVCP, please follow this link:

VVC intervention evaluations | What Works Centre for Crime Reduction (college.police.uk)


If you would like to receive our regular College What Works email updates, contact us at whatworks@college.pnn.police.uk and ask to be added to our mailing list.