The parents of a woman found dead on the floor of her flat are calling for the organisation responsible for her to face corporate manslaughter charges.
Ruth Mitchell, 40, who had schizophrenia, died in September 2012 from the effects of malnourishment.
A Safeguarding Adults Review published on Thursday has found there were missed opportunities to help her.
Plymouth Community Healthcare, now Livewell Southwest, has admitted failings and apologised.
Despite her parents Russell and Anne Mitchell raising concerns in 2007 that her condition had deteriorated, her mental health care was reduced from "enhanced" to "standard", the review said.
At the time of her death she had only a kitchen chair and table, a microwave and a fridge in her home. She had been sleeping on a bare floor.
Her flat had no heating or hot water for the last four years of her life, and she had isolated herself from her family and professionals.
The review highlighted a failure of mental health services to work with other agencies such as her social housing provider and the police to understand the extent of her illness.
It said mental health professionals didn't look at the risks and were too reliant on Ms Mitchell's own description of how she was.
The review also highlighted "poor" record keeping.
Assessments, with one exception, "did not take account of third-party concerns about Ruth or observations of her environment".
'Indifference and neglect'
Mr Mitchell will write to Devon and Cornwall Police to ask them to consider a criminal investigation.
"I think professional indifference and neglect was responsible for the death of my daughter and it needn't have happened and I think that's the tragedy of it," he said.
Recommendations made in the review include improvements to information sharing among agencies and record keeping.
It also calls for support for the physical health of people with mental health problems and better understanding of a person's capacity to make decisions.
The Parliamentary and Health Service Ombudsman previously ordered Livewell Southwest to pay £7,500 to Ms Mitchell's family, and the Nursing and Midwifery Council found a mental health nurse guilty of two counts of misconduct in relation to the case.
Stephen Waite, chief executive of Livewell Southwest apologised and said: "There were failings and we have made significant progress in rectifying those failings, and the services and systems in place now are very different to what was in place a number of years ago."
Devon and Cornwall Police declined to comment as it has not yet received a letter from Mr Mitchell.