In a damning report on the state's youth justice system, Children's Commissioner Aileen Ashford said the $10 million spent each year running Ashley in the state's North would be better spent on alternative programs to help young offenders turn their lives around.

On average 25 young people are detained at the 51-bed facility on any given day and fewer young people are being locked up each year.

``Tasmania needs a secure detention facility for some serious juvenile offenders,'' Ms Ashford said.

``What it cannot afford is to continue to fund the Ashley Youth Detention Centre.''

Ms Ashford said the lack of support for young offenders once they were released meant it was more than likely they would reoffend.

``My fear is that we've got young people here at the moment who will keep coming back and forth, which they have been doing for many, many years and that they will graduate to Risdon and that they have a sense of hopelessness too, which is really sad.''

She also criticised the state government's failure to develop a comprehensive, long-term strategy for the youth justice system.

Children's Minister Michelle O'Byrne agreed with Ms Ashford's findings.

``I believe a smaller, less expensive secure facility, combined with expanded investment in alternatives to detention, would produce better outcomes for our young people and our community,'' Ms O'Byrne said.

However, any possible changes were in the very early stages of planning.

Ms O'Byrne highlighted $1.4 million of government funding allocated to the Targeted Youth Support Service that works intensively with 10- to 17-year-olds at risk of entering the youth justice or child protection systems.

Legal Aid director Norman Raeburn said early intervention would deliver wider community benefits.

``The further a young person becomes enmeshed in the standard criminal justice system the greater the likelihood they will stay enmeshed in it for significant periods of their adult life,'' he said.

Save the Children runs Hobart-based programs for young people on bail and leaving detention but there were no programs targeting youth from the North or North-West.