A young Aboriginal woman, the victim of fetal alcohol syndrome, has spent 18 months locked up in an WA jail, despite having not been convicted of a crime.

An Aboriginal woman born brain-damaged with fetal alcohol syndrome is stuck in limbo in a West Australian prison after the Northern Territory government reneged on a promised offer of a place in a special care home.

Former NT policeman Ian McKinlay, who is Roseanne Fulton’s adult guardian, said she had been locked up without conviction in a Kalgoorlie prison for 18 months.

The WA court system declared her unfit to be tried after the 24-year-old was charged with driving offence.

She grew up in an abusive home in Alice Springs and spent her teenage years homeless and sleeping in a river bed, Mr McKinlay said.

Mr McKinlay said the NT government had promised her a place in a secure group home in Alice Springs called Kwiyernpe House.

“Just weeks ago they backflipped on their commitment,” he told AAP.

“They’re claiming she’s incompatible with the two male clients in that facility.”

He speaks to her daily by phone.

“She’s just bewildered, she doesn’t know why she’s there and why she’s stayed so long,” Mr McKinlay said.

“She’s very child-like … but she’s very open to receiving help.”

Mr McKinlay estimated there were about 30 other intellectually disabled Aboriginal people in jails across the NT, Queensland and WA because of a lack of proper facilities to care for them.

“Governments have been happy to let this be cloaked (in secrecy) because of the silence of the high-needs people,” he said.

Victoria and NSW instead operate disability services and special accommodation and support services for such cases.

A spokeswoman for NT Health Minister Robyn Lambley declined to comment.

The NT health department said it held the health and wellbeing of clients as paramount but could not comment on specific cases for privacy reasons.