The family of a Perth mother who committed suicide in Mexico with a euthanasia drug hope an inquest next month will lead to "accountability" for her death.
They believe failures in WA's mental health system allowed her to be discharged from a clinic despite evidence of her suicide plan.
The WA Coroner's Court has confirmed an inquest into Erin Berg's death will begin on February 25.
It will look at the care WA's mental health system gave the 39-year-old mother of four.
The inquest comes after a six-month review of WA's mental health services found they were overstretched, under-resourced and fragmented.
Recent cases include a man who was mistaken for an escaped Graylands patient being detained and given strong antipsychotic drugs that made him ill. Another man was wrongly locked in the psychiatric ward of a Perth hospital for more than a month.
After almost five years fighting for answers and justice, Ms Berg's sisters Sally and Chris Doyle hope the inquest will be a public examination of the "terrible mismanagement" of Ms Berg's case and expose the system they say failed her.
"Our hope is that any aspects of her care we may be unaware of come to light but primarily we would like some clear directions and recommendations that will place pressure on WA Health and the Mental Health Minister to fix up their act," Sally Doyle said. Ms Berg, a mental health outpatient with severe postnatal depression after the birth of her fourth child, flew to Mexico in April 2008 to buy Nembutal after reading right-to-die campaigner Philip Nitschke's book Killing Me Softly. She died in hospital after 10 days in a coma.
Staff at King Edward Memorial Hospital's mother-baby unit, where Ms Berg was an involuntary patient, reported evidence of her suicide plan, including a passport application, a library slip for Dr Nitschke's book, traveller's cheques and an itinerary in Mexico.
But she was still released under the care of Fremantle Hospital's Alma Street clinic.
A report by WA chief psychiatrist Rowan Davidson said the clinic gave Ms Berg only "superficial" treatment.
As social workers, the Doyle sisters believe if lessons had been learnt from Ms Berg's death, lives could have been saved.
"It kills me that this is happening again and again to other families," Chris Doyle said. "It's not about expecting a system to be perfect, it's about expecting a system to be accountable and to learn."
Ms Berg's sisters and her husband Norman Berg, on behalf of their four children, are suing the Health Department for negligence.
If you or someone you know is thinking about suicide, call Lifeline on 13 11 14.