All short-term prison sentences for young adults convicted of non-violent offences should be abolished, a charity has said.

The Transition to Adulthood (T2A) Alliance made the call as it launched a report on young adults and the criminal justice system.

The report says thousands of vulnerable young adults with mental health problems, learning difficulties, drug and alcohol addictions, and backgrounds in homelessness and care, are being funnelled unnecessarily into the criminal justice system.

The T2A Alliance argues the majority could use support services in the community before they have to enter the criminal justice system and, if sentencing is appropriate, they should be given community sentences.

The report outlines 10 policy proposals to reform the approach to young adults and calls for them to address key stages of contact the criminal justice system: diversion away from offending, sentencing, custody and resettlement after release.

A third of all offenders, a third of all those sent to prison, and a third of all those on probation are between the ages of 18 and 24, the T2A Alliance said.

Deputy Chair of the T2A Alliance Shan Nicholas said: "It is clear that the current system is failing young adults and as a result failing society. As many of us with adolescents of our own know, young people do not suddenly become mature and fully responsible adults at the age of 18.

"The ages of 18 to 24 are the most critical stage of young people's lives, as they discover their paths in life and learn to fully take on adult responsibilities. If we continue to ignore the most basic needs of young people who are caught up in criminal activity and do not have the resources or understanding to get themselves out of it, we will continue to see a large swathe of our younger generation becoming entrenched on pathways to a lifetime of crime."

The independent research, commissioned by the T2A Alliance, found that that if all low-level, non-violent young adult offenders in a typical year were made to engage with their victims and make amends via restorative conferencing rather than being sent through the criminal justice system, £275 million could be saved over their lifetimes.

The research also found that if all adult offenders between 18 and 24 given short term prison sentences in a year received community sentences instead, £12 million could be saved over their lifetimes.

In a separate piece of independent representative polling for the T2A Alliance, 151 MPs were also asked their views on the issues related to the policy paper.

It found 62% of the MPs asked support replacing all short-term prison sentences for young adult offenders convicted of non-violent and non-sexual crimes with community alternatives

The report calls for a 'triage system' where low-level offenders are assessed by police over whether they should face the criminal justice system or be dealt with in the community.

Two thirds of MPs polled (66%) support proposals for police to have more discretion on this issue.

Once in the criminal justice system, the report says that 18-24s should be treated as a distinct group when being sentenced. It also calls for the courts to assess the level of maturity and development of each young adult offender and allow some to be tried under juvenile law. Some 76% of the MPs polled supported this proposal. 

Finally, the report stresses the need for an increase in the support offered to young adult offenders once they leave custody to ensure they do not re-offend.

It recommends that Young Offender Institutions are twinned with Further Education Colleges to encourage those detained to gain qualifications.

Support should also be provided for young adult prison leavers on the same level as support given to those leaving care, it said. Some 86% of all MPs polled endorse this proposal.  

The T2A Alliance is campaigning for the 10 proposals to be endorsed in all three main political party manifestos for the 2010 general election.

Dominic Grieve, the Conservative shadow minister for justice, attended the T2A Young Adult Manifesto launch.

He said: "Many of the proposals being recommended by T2A are in fact things that I would endorse.

"That young adults are recognised as a distinct group in the criminal justice system on account of their developmental stage, I entirely endorse that. The evidence for this is overwhelming."

He said restorative justice "appears to be very effective".

On calls for offenders leaving custody to be given more support, Mr Grieve said: "People stop re-offending if they are in an environment where they can find work, security of a place to live and are not surrounded by habitual offenders. It is entirely essential that every single person being released from prison will have programmes to get them into work and housing."

The Transition to Adulthood (T2A) Alliance is convened by the Barrow Cadbury Trust and includes among its members the Centre for Crime and Justice Studies, the Criminal Justice Alliance, crime reduction charity NACRO, The Prince's Trust and The Prison Reform Trust.

To read the full report and see the 10 policy recommendations, visit www.t2a.org.uk/publications.