The brother of a woman killed by an insane man released on bail after trying to kill a workmate says the justice and health systems failed his family and the killer.

Aucklander John Royal said yesterday he bore no malice towards Jesse Moore, 24, of Otaki, who killed Lorraine Patricia Royal, 43, at rural Manakau, last October 1.

Moore, whose father Graham was Lorraine Royal's former partner, was this week found not guilty of her murder by reason of insanity.

On the same grounds, he was also found not guilty of attempting to murder the workmate.

The hearing in the High Court at Palmerston North before Justice Warwick Gendall was the first to be heard under the Criminal Proceedings (Mentally Impaired Persons) Act 2003, which came into force this month.

That allowed the judge alone to determine before a trial whether the accused was not guilty due to insanity.

Justice Gendall said the new act allowed him to rule insanity on three conditions: that the accused suffers from a mental disorder; that the prosecution agrees that the only reasonable verdict is not guilty by reason of insanity, and that the judge is convinced by expert evidence that the accused was insane within the meaning of the law when the offence was carried out.

Mr Royal said he expected the verdict but it never should have got to that stage.

"The system seems to have let Jesse down as well as my sister, and allowed him to be on bail when he'd already carried out an assault on one of his best friends ...

"It's just another example of the people who do the psychiatric reports and assessments letting both our family and Jesse's family down.

"No one's listening, are they? No one appears to be listening to what the police are saying or what the professionals are saying.

"They were warned and obviously the powers-that-be that made the report believed that he was fine to be let go, but that was shown to not be the case because we lost our sister."

Lorraine was one of seven brothers and sisters.

"She had a tough life," Mr Royal said. "She found things quite difficult but she was a fighter. She definitely cared about a lot of people."

On September 30, Moore went to the home of a 49-year-old workmate in Otaki. They sat down and drank tea but, shortly afterwards, Moore smashed his mug into the other man's face.

He then knocked the man to the floor and began punching him in the head, saying: "You have to die and I have to kill you."

The man escaped and hid in nearby bush. Moore followed him with a pair of scissors and a 1.8m metal bar.

Police were called by neighbours and Moore was arrested. The workmate needed 20 stitches to his face.

Moore appeared at Porirua District Court the next morning, where Judge Barry Lovegrove released him on bail, against police opposition.

That night, Moore awoke in an agitated state and left home for Otaki beach. His partner called friends to help her to find him.

Moore's father and Ms Royal helped to look for him. They found him and took him to his father's house. He persuaded Ms Royal to leave with him and drove her to the entrance of Otaki quarry.

They left the car and Moore hit Ms Royal over the head with a large rock, put her back in the car and drove to a single-lane bridge on North Manakau Rd, 18km north of Otaki.

He then dragged her under the bridge, where he tried to strangle her before hitting her repeatedly with the rock.

When he was picked up by police, Moore said he had struck Ms Royal "to remove Satan from her".

Justin Walsh, a forensic psychiatrist, told the court he talked to Moore shortly after his arrest and found him to be in an excitable state.

"He was aroused, fearful and displayed confusion and uncertainty.

"He described a number of beliefs that were clearly delusional. They were religious in nature - he believed that he was in combat with Satan and alluded to believing that the world was coming to an end."

Dr Walsh said it was "abundantly clear" that Moore met the Crimes Act criteria for legal insanity - to be unaware of the nature and quality of his actions or whether they were right or wrong.

Associate Professor Phillip Brinded, said it would be "inconceivable" to think that Moore was not suffering from a psychotic illness at the time.

Justice Gendall remanded Moore back to the secure unit of Porirua Hospital.

Deadly days

* Jesse Moore, 24, bashed Lorraine Patricia Royal, 43, to death with a rock near Otaki last October 1.

* Two days before, he had smashed a tea mug into the face of a 49-year-old workmate, punched him in the head and chased him into bush armed with a pair of scissors and a 1.8m metal bar.

* A judge granted Moore bail, over the opposition of police.