Psychiatric patient Paul Ellis, who beat his father to death with a baseball bat after being released from compulsory mental health care, is suing health authorities for $180,000.

If his case in the High Court at Auckland, before Justice Judith Potter, succeeds it will be the first time in New Zealand a person who has killed someone is compensated because another party was negligent.

Ellis, who clubbed his father to death on October 26, 2001, was found not guilty of murder by reason of insanity and is now a fulltime patient at the Mason Clinic.

On October 11, 2001, Ellis, a father of two, was admitted to Middlemore Hospital's mental health unit, Tiaho Mai, as a compulsory patient suffering a suspected psychotic episode.

He was discharged into the care of outpatient service The Cottage the following day, after demanding a review of his status under the Mental Health (Compulsory Assessment and Treatment) Act.

A statement of claim presented by Ellis' lawyer Antonia Fisher said when Ellis was seen by the judge reviewing his status he was coherent.

The judge granted Ellis' discharge after taking into account the view of a consultant psychiatrist who, at that stage, had not even examined Ellis.

The consultant psychiatrist did examine Ellis before he left the hospital but did not deem him a risk to himself or others.

The claim said Counties Manukau District Health Board breached a number of its duties to provide Ellis reasonable and appropriate care and ensure that he did not become a risk to himself or others.

It also said staff failed to monitor his mental health while in the community and transfer him from inpatient to outpatient services with reasonable skill and care.

Counsel for the health board, Michael Ring, QC, told the court that staff followed requirements set out by the act.

An application to strike out the claim said there was no enforceable duty of care and Mr Ring said yesterday there was no legal precedent.

The court heard that between October 19 and 25, 2001, staff from The Cottage tried to contact Ellis by letter and telephone and he refused a home visit.

Ellis' statement of claim said that while that was happening, between October 14 and 24 Ellis' family repeatedly contacted outpatient services worried about his behaviour.

On different occasions Ellis' family said he thought he was "the saviour" and acted irrationally by dumping furniture and rubbish at his father-in-law's house.

His wife and two children feared for their safety, his mother was afraid of him, he chased his family down the motorway on his motorbike and was banned from a school after abusing a family member and school staff.

The abuse at the school happened two days before he killed his father.

Ellis' brother Clive, who has flown from Perth for the hearing, said outside court the treatment his brother received was abysmal.

"No one has been held accountable," he said.

"If the health system ends up a little better off for this then it's good. I just wonder how it ever happened really."

The hearing is set down for three days.