The father of a woman beaten to death in a Melbourne park is suing Corrections Victoria for alleged negligence in letting her killer walk free beforehand.

Henry Hammond was on a community correction order when he attacked 25-year-old Courtney Herron with a tree branch for 50 minutes at Royal Park in May 2019.

He was in the grip of schizophrenia and last year found not guilty of murder by way of mental impairment. Hammond was ordered to spend 25 years in a psychiatric facility.

The victim’s father, John Herron, is suing the Commissioner for Corrections Victoria for alleged negligence over the release of Hammond from custody the month before the attack.

In a writ lodged in Victoria’s Supreme Court on Tuesday, Mr Herron said Corrections Victoria was also negligent in its supervision of Hammond while he was on the order.

Hammond had been released on appeal against a 10-month jail sentence for offences including making a threat to kill.

Ms Herron had been sleeping rough after battling mental health and drug issues. Photo: Victoria Police

He should not have been assessed as suitable for a 12-month community order because he was homeless and required help for substance abuse, the writ said.

It also said Hammond lacked family support, had refused counselling in custody and there was no psychiatric evaluation of him while he was there.

“No reasonable corrections officer” would have concluded a community order was suitable in those circumstances, the writ said.

There were conditions that Hammond be assessed and receive treatment for drug, alcohol and mental health issues as directed by corrections authorities.

The writ said this didn’t happen and Hammond was not in regular contact with his supervisors between his release on April 1 and Ms Herron’s death on May 25.

She met Hammond the day before and invited him to join her friends in smoking ice.

The group was uneasy about Hammond tagging along. Early the next morning, he and Ms Herron went for a walk.

Hundreds of people gathered at a vigil for Ms Herron after her death. Photo: AAP

Hammond picked up a tree branch and Ms Herron asked, “Are you going to kill me?”

He spent the next 50 minutes beating the woman to death before tying her legs together and dragging her body into a clearing.

Mr Herron wants damages for chronic post-traumatic stress disorder and adjustment disorder following his daughter’s death.

He worked as a lawyer and for the justice department at the time but said his psychiatric injuries had caused him economic loss.

The Corrections Victoria commissioner when Ms Herron died was Emma Cassar. She is now the head of COVID-19 Quarantine Victoria.