Jon Venables – The Offender Assessment System


James Bulger, Jon Venables and the Offender Assessment System

Jon Venables and his accomplice Robert Thompson were 10 years old when they abducted and murdered James Bulger. They were released on licence in 2001 after eight years, having never served time in an adult prison.

The Guardian recently reported that a psychiatric evaluation of Jon Venables carried out before his release from prison concluded that he posed a “trivial” risk to the public and that the likelihood of him re-offending was “so negligible as to not amount to a serious consideration”.

They were told then that if they breached the conditions of their release they could spend the rest of their lives in jail.

A Ministry of Justice spokeswoman said: “We can confirm that Jon Venables has been recalled to custody following a breach of licence conditions.”

Details of the breach have not been given, but the conditions of the murderers’ release stated that they could not return to Merseyside without permission, and that they could not contact each other or members of the Bulger family. Any criminal offence would also result in a return to prison. So, how is risk assessed?

OASys – Offender Assessment System
It is vital the risk a prisoner poses is properly assessed if they are to progress through the prison system. It is also important prisoners understand how they can demonstrate a reduction in risk, especially if they are subject to release by the Parole Board.

OASys is the abbreviated term for the Offender Assessment System, used in England and Wales by HM Prison Service and the National Probation Service. It is considered to be the most advanced system of its kind in the world. It is the foremost risk assessment tool for the purposes of sentence management and resettlement.

This risk assessment tool was rolled out in 2002 to measure the risks and needs of criminal offenders under their supervision. It also has an important part to play in reducing re-offending and improved public protection. A similar system known as ASSET is used for offenders under 18 years of age.

The OASys is a sequence of computer based forms which are broken down into ten different areas addressing each of the factors listed below:

Offending history and current offence
Social and economic factors: including access to accommodation; education, training and employability; financial management and income; lifestyle and associates; relationships, drug and/or alcohol misuse
Personal factors: thinking and behaviour; attitude towards offending and towards supervision; emotional factors such as anxiety and depression.
The main part of the OASys document examines the above factors which research has shown can predict the likelihood of an offender being reconvicted and the risk of harm he or she poses to the public. This is carried out by way of two offending predictors; the OASys general reoffending predictor (OGP) and the OASys violence predictor (OVP). OASys also contains a section on sentence planning as well as a self-assessment questionnaire which the offender is asked to complete. The questionnaire gives an important opportunity for the offender to comment on how he or she sees himself/herself and his/her offending.

The OASys document is based on previous documentary records and an interview with the prisoner. It scores the offender on both the risk of re-offending and the factors that have contributed to their criminal behaviour, whether it’s a lack of a job or home, or a problem connected to drug or alcohol abuse. Scores are attributed to each of the areas and totalled together. Up until August 2009 the maximum achievable score was 168 based on responses to 73 questions. Now the total score will be out of 100 and is based on 40 questions. The scores are then placed into ‘bands’ identifying the level of the risk of harm to the public. The levels of risk of harm used in OASys are:

Low – No significant, current indicators of harm.
Medium – There are identifiable indicators of risk of harm. The offender has the potential to cause harm but is unlikely to do so unless there is a change in circumstances, e.g. loss of accommodation, a lapse back to drug or alcohol misuse.
High – There are identifiable indicators of risk of harm. The potential event could happen at any time and the impact would be serious.
Very high – There is an imminent risk of harm. The potential event is more likely than not to happen imminently and the impact would be serious.
An OASys assessment will be carried out at the stage that the pre-sentence report (PSR) is produced, with further assessments conducted periodically throughout the sentence (whether in custody or in the community) and at the end of the sentence when an offender may be on licence . Typically this is carried out every 16 weeks for offenders in the community or annually for IPP prisoners. Any prisoner subject to release by the Parole Board can expect to have an OASys document included within the parole dossier.
PSO 2205 states that the key aims of OASys are to:

Assess how likely an offender is to re-offend
Identify and classify offending-related needs, including basic personality characteristics and cognitive behavioural problems
Assess risk of serious harm, risks to the individual and other risks e.g. to the public at large
Assist with management of risk of harm
Link assessments, supervision and sentence plans
Indicate the need for further specialist assessments or intervention
Measure change in risk during the period of supervision or sentence
The difficulty with an OASys assessment is it is highly subjective. This means that one qualified probation officer may not interpret the same information in the same way as another qualified probation officer. Risk assessment is not an exact science and not set in stone. Unfortunately this results in an inconsistent approach. Continuing on from this, is that historically, the responsibility for preparing an OASys used to lie with the prison. The prison assessed on what the position was there and then i.e. in prison. A different criteria has been adopted by probation who assume for the exercise the offender is to be released into the community on the day of the assessment. It is not surprising therefore that when the prison undertook assessment the scores obtained were often lower than when it was undertaken by probation.

In these instances it is important to consider both the previous and current OASys, to check for obvious errors. Given that several people have access to the document over a period of time it is important the ‘opinions’ don’t suddenly turn into ‘facts’! I have seen OASys assessments that have been over-scored and contain factually incorrect information that offenders have been trying to challenge for years.

When that happens it is important to contact a specialist prison law solicitor to assist in challenging the contents of the document. The OASys is often referred to as a ‘locked document’ which means any information stored on it cannot be removed. It can however be amended by way of further entries by the probation officer. A probation officer is entitled to express their professional opinion within the document which can be challenged by way of representations, however factually incorrect material which affects the assessment of risk should be challenged at the earliest opportunity.

For more information about prison law, please contact us.

Share this article…

  • Linkedin
  • Google+


We want people to have access to a local Hine solicitor, and we choose each office with care so that we can make a genuine contribution to the local community. Growing customer numbers mean that we are opening offices in new UK locations to meet increased demand.

Find your nearest Hine Solicitors office here …



“My solicitor was a pleasure to work with, very professional and information. It was nice to know I could trust her” “I was…

Prison Law

“You have been fantastic in dealing with my case and I am really happy that it has now gone to an oral hearing….


How can we help? Request a callback...

    Please refer to our Privacy Policy for details of how and why we process your data.

    You can also view our GDPR Recruitment Policy here.