Lord Bradley's report on people with mental health problems and learning disabilities in the criminal justice system (The Bradley Report, 2009) recommended that all police custody suites and criminal courts should have access to liasion and diversion services. 

This recommendation has been supported by successive governments and, in March 2016, liaison and diversion services provided around 53% population coverage across England. A further investment of £12 million was announced in July 2016, which will result in 75% population coverage by 2018. Subject to full business case approval by HM Treasury, 100% roll out is expected by 2020. Similar services exisit in Wales and these are known as criminal justice liaison services. 

Liaison and diversion is a process whereby people of all ages with mental health or substance misuse problems, learning disabilities, autism, and other needs are identified and assessed by appropriately qualified staff as early as possible as they enter the criminal justice system. 

Liason and diversion services seek to improve health outcomes and reduce re-offending by providing early intervention for vulnerable people as they first come to the attention of the criminal justice system. Information from liaison and diversion assessments is shared appropriately and proportionately with members of the judiciary and court staff to help inform criminal justice decision making and reasonable adjustments to court proceedings, where necessary. Where appropriate, information should also be used to inform pre-sentence reports.

 A 2015 survey undertaken by the Magistrates' Association found that where liaison and diversion services exist, magistrates say they receive information from assessments concerning defendants at an earlier stage, are more confident that they are getting the information they need, and are more confident in asking further questions about the defendant-each of which impacts their decision making. 

Police custody and court staff may recognise when an individual has a particular vulnerability and can make a referral to their local liaison and diversion service. Individuals who have been seen by liaison and diversion and criminal justice liaison services will either continue through the criminal justice system, with the necessary support, or be diverted away from criminal justice and into healthcare for treatment and care. 

In England, liaison and diversion services are commissioned by NHS England, and reflect a common service specification, which includes children and adults, and a wide range of mental health, disability, substance misuse and social vulnerabilities. In November 2013, following a period of consultation, implementation guidance for criminal justice liaison services was issues by the Welsh Assembly Government.

A major role for liaison and diversion services in England, and criminal justice liaison services in Wales, is to help identify and, where necessary, assess people who might have mental health conditions, learning disabilities and other vulnerabilities when they first come into contact with the criminal justice system, and to make referrals to appropriate services. Police custody and court staff may recognise when an idividual has a particular vulnerability and can make a referral to their local liaison and diversion service. Individuals who have been seen by liaison and diversion and criminal justice liaison services will either continue through the criminal justice system, with the necessary support, or be diverted away from criminal justice and into healthcare for treatment and care.

Liaison and diversion and criminal justice liaison practitioners should be aware of the legal obligations and guidance that will help to facilitate support for vulnerable defendants; and these include:

• reasonable adjustments for defendants with disabilities, as required by the Equality Act 2010
• special measures, as provided for at section 47 of the Police and Justice Act, 2006
• relevant guidance issued to members of the judiciary and court staff, for example, the Consolidated Practice Direction and Guidance for the judiciary and HMCTS staff including the use of registered and non-registered intermediaries for vulnerable defendants and vulnerable defence and prosecution witnesses.

Liaison and diversion and criminal justice liaison practitioners should also be aware of the inherent power of members of the judiciary to ensure that necessary support is made available to defendants, according to their personal need, to help ensure their effective participation in court proceedings and to uphold their right to a fair trial.

Further information about liaison and diversion services, including whether services exist in your area, can be found at NHS Commissioning: liaison and diversion.

Further information on local services including details of a liaison and diversion team working in your court should be available from your local mental health and learning disability champion. More information on a champions' role can be found in 'Magistrates' Association Mental Health and Learning Disability Champions'.