"I didn't understand the evidence, and all the stuff police give you, or legal aid," he said. "Sometimes people with a disability or mental health problem are uncomfortable speaking with police and legal people.

"Of course [I was] scared and also I've got low self-esteem.

"I'd spent lots of my teenage years and adult time in courthouses because I didn't recognise I had a disability 'til later on in life," he said.

His predicament could have ended in remand, again, or worse, but on this occasion, a few years ago, Mr Thomas received help that turned his life around.

He got the support of the Intellectual Disability Rights Service, a small advocacy group that helps over 600 people a year with intellectual or cognitive disabilities navigate the police and court systems. They do things like ensure everyone understands what is going on and that people show up to court on time, often steering them to cost-effective, diversionary measures that keep particularly vulnerable people out of jail.

It runs on volunteers and $1 million a year from the Department of Family and Community Services' (FACS) Ageing, Disability and Home Care arm.

"The criminal justice system is often adversarial, and doesn't have the protection of a person with an intellectual disability at its heart," said Mike Sprange???, chairman of the group and a volunteer himself.

"People with an intellectual disability tend to get a very negative outcome with police or courts unless they get a support person."

But the future of the IDRS, and many other small disability advocacy organisations like it, are in doubt as they are set to lose their state government funding from July next year.

Under the terms of NSW's National Disability Insurance Scheme deal with the federal government, it is handing all its disability budget to the Commonwealth from July 1, 2018.

The problem is that the NDIS has a narrower definition of disability support, and excludes advocacy and health-related services.

Advocates say they have been flagging this problem to the state government for two years, but have got nowhere.

"There are a range of community-based and collective support services which are responsive to crisis which haven't been included in the NDIS," said Associate Professor Leanne Dowse, a disability expert from UNSW. "Organisations like this have been caught up in the move to individualised funding and a market-based solution."

Other states have cut different deals, keeping "residual" funding to cover advocacy and health services, Professor Dowse said.

NSW programs including a network of specialist nurses who help people with disabilities in the hospital system; regional specialist psychiatry services; and advocacy services from Disability Advocacy NSW which helps 1800 people a year are among those falling through the gap with the IDRS's criminal justice support service.

Mark Grierson, the CEO of Disability Advocacy NSW, said they will have to close several regional offices and make staff redundant from next year without the current state government funds of about $700,000 a year.

"I've tried to talk to all the relevant ministers," he said. "I say, it's a very small pot of money, and parts of the state are going to be empty of advocacy all together when this happens. I just don't get a response."

Or, as Janene Cootes, the executive officer of the IDRS puts it, "We are very supportive of the NDIS and think it would deliver some really good things for people, but we happen to be collateral damage."

Asked if the state government would find the funds for the affected programs, a spokesman for FACS said "from July 2018, the NSW government will transfer every dollar of our disability budget directly into the NDIS, where it will be used to provide supports to the people who need them.

"Systemic advocacy, legal review and representation will be funded outside the NDIS ??? through Commonwealth funded programs."

The NSW Department of Justice declined to comment on whether it would take over supporting the IDRS's criminal justice service.

Since the network helped him out of his legal problem, Mr Thomas has made it his mission to help people with similar disabilities.

"I'm able to help others now," he said. "I've created workshops and I'm teaching younger generations how to set themselves a goal and take steps to achieve it. And to speak up if they feel they've been discriminated against."