Policy paper

Operation Bluestone - Tilley 2011

Main project objectives To improve the detection rate for rape and reduce the high victim declines to prosecute rates within the city of…

This was published under the 2010 to 2015 Conservative and Liberal Democrat coalition government


Operation Bluestone - Tilley 2011 (PDF file - 202kb)

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Main project objectives

  • To improve the detection rate for rape and reduce the high victim declines to prosecute rates within the city of Bristol

Organisation name:  Avon and Somerset Police
Part of a wider programme:  Tilley
Partnership agencies contributing to this project:

  • CPS
  • One25 Project
  • SARC
  • Safer Bristol
  • Bristol Drugs Project
  • Nextlink

Areas addressed by project:

  • Violence against Women and Girls
  • Rape and Sexual Assault

Did the project involve an offender?  Yes
Sex of Offender:  Male
Type of Offender:  Domestic Abuser / Sexual Abuser
Age of Offender:  Various ages
Did the project involve a victim?  Yes
Age of the victim?   Various ages
Sex of the victim?  Both
Type of victim:  Domestic violence / sexual abuse
Region where project took place:  South West
Type of area that project took place within:  Mixed
Start and end date:  Project start 21 Sept 2009 - Project now ongoing


In the years before Bluestone was formed Bristol was under-performing in terms of rape and sexual assault detection and conviction rates when compared against other forces, despite the fact that figures were low nationally.

In the financial year 2006/7 the rape detection rate in Bristol was just 21% which significantly contributed to the entire force receiving a national rating of poor.
In 2007/8 the rape detection rate increased to 25.3% following the introduction of the Sexual Assault Investigation Team (SAIT) in May 2006 but clearly there was significant room for improvement.

The low detection rate of rape and sexual violence for the city and the low conviction rate contributed to making Avon and Somerset significantly below the national average in gaining justice for victims.

In the year proceeding Bluestone’s formation over a third of all victims reporting rape or sexual assault declined to assist the police with the investigation.
In summary, the analyses indicated the following factors as causes for the poor detection rate:

  • inexperienced investigators
  • unmotivated investigators
  • lack of communication with the investigation team
  • inconsistent supervision of rapes
  • lack of evidence/failure to maximise evidential opportunities
  • poor relationship with CPS
  • lack of common approach with the CPS

And the following factors as the causes for the Victim Declines to Proceed Rates:

  • poor victim treatment in court
  • fear of reporting to the police
  • lack of support


** The Bristol response to the problems identified was the creation of Operation Bluestone, a specialist unit developed to investigate all cases of rapes and serious sexual assault in Bristol.

Five elements were the guiding principles and were incorporated into all aspects of the work that Bluestone completes:

  • Greater public awareness of what is acceptable in sexual relationships and what rape is
  • Trust and confidence in the services available sufficient for people to come forward and seek help when they have been raped
  • Excellent victim centred care, support and advocacy services that help victims get over their trauma, immediately and in the days, weeks and months that follow
  • Specialist, committed and dedicated police officers who will pursue the perpetrators with comprehensive, open minded and ethical investigations
  • Prosecutions and trials that see the police, CPS and the care givers working together in support of the victim, so that she or he can present their case in a clear and compelling way and see justice done.

Evaluation Details: 

A year after implementation an evaluation of Bluestone took place and has been collated from a number of different sources.  Interviews have been held with Bluestone managers and staff and these are supported by quantitative analysis.


** The results for the two key statistical indicators as of the 21st September 2010, were:

  • Detection rate - increased by 24% 
  • Victim Decline to Proceed rate - decreased by 38%

**Other Benefits: 

** Better confidence amongst women that we will achieve a result in court

Most important lessons:

  • Victim care is paramount to increase detection and conviction rates.  It was highlighted that victim care with ASC needed significant improvement
  • Alignment of specific offices to tackle the problem is important when investigating this type of crime.  Now dedicated SAIT officers have teamed up with third sector agencies like the CPS and have provided training so that the wider audience understand the issues surrounding a subject that has a lot of stigma attached to it.  This in turn means jurors have a wider understanding
  • Prevention and raising awareness around the issue has been a specific learning point.  Makin the wider Avon and Somerset community aware of the Force’s dedication and understanding of such issues has increased confidence.  Victims are now aware help and support is available to all

Contact Name:  Andrew Coggins (Detective Constable)
Email Address:  andrew.coggins@avonandsomerset.pnn.police.uk
Organisation:  Avon and Somerset Police
Alternative Contact:  Kate.Woolgrove@avonandsomerset.pnn.police.uk

This evaluation shows the findings of one of many successful approaches to reducing violence against women and girls. 

By promoting this material on the Effective Practice Publications area of the Home Office website we are not implying that this is the only effective approach to reducing violence against women and girls, we are merely suggesting that this is one approach that appears to yield successful outcomes.


Date: Mon Aug 22 16:05:52 BST 2011

Full Document

Published 22 August 2011