Killer father, Greg Anderson, was capable of murder and not mentally ill, a police officer has told the coronial inquiry into Luke Batty’s death.

Senior Constable Paul Topham said the Anderson-Batty family was a tragedy waiting to happen but Anderson was not mentally ill.

· Parliament ready for attacks: PM
· Canada parliament attack: eye-witness account

Sen Const Topham told the inquest Anderson was never diagnosed with mental illness and he saw no signs of mental instability.

“Without a question in my mind, as we say, he was 100 per cent bad… not mad,” he told the court.

“His demeanour… he had no regards for authority whatsoever… whatever we did for this guy, he didn’t care.

“He knew what he was doing.”

However, Sen Const Topham also told the inquest that Anderson’s behaviour was deteriorating every time he saw him and that he believed he was capable of killing.

“If he didn’t do it on the 12th of February he would’ve done it further down the track,” he told the inquest.

“The writing was on the wall.”

Sen Const Topham was one of the first police on the scene the day Luke died and said he immediately realised what had happened when he heard his mum, Rosie Batty, screaming.

Anderson clubbed his 11-year-old son Luke with a cricket bat then attacked him with a knife as they played together in the nets after cricket training at Tyabb on February 12, 2014.

At the coronial inquest into Luke’s death, Ms Batty accused authorities of not doing enough to protect her son. She broke down repeatedly while giving evidence earlier this week.

Sen Const Topham told the inquest today he had “a large number” of conversations with Ms Batty in the year before Anderson killed Luke and was aware Anderson consistently failed to turn up to court hearings about their son.

He said he believed Anderson was highly intelligent and knew how to work the system.

The court heard that he arrested Anderson in January 2013 and a video recording of Anderson’s police interview with him was played at the inquest, in which Anderson appeared aggressive and refused to answer questions.

Ms Batty sobbed quietly as she watched the interview with Anderson 13 months before he murdered their son, in which he said “You have nothing, I wish to leave”.

The interview ended when Anderson sat cross-legged in the corner of the room, facing the wall.

“You’re supporting a lie by someone who has done it to me before,” he told police.

Sen Const Topham said he was stunned when a magistrate granted Anderson bail the day after the interview despite a courtroom rant and him having no fixed address.

“He is nuts,” Sen Const Topham said of Anderson in an email to a colleague.

“He is contesting all matters and will only answer to Jesus, he even told the magistrate that and still got bail.”

He said police had worked hard to arrest Anderson and keep him in custody, but were continually frustrated by the courts and mental health system which kept releasing him.

“What do we do with someone like this?”

“We put him up against the courts, the courts let him out.”

He also bemoaned a “glitch” in the former police database system which meant an officer could be holding a warrant which wasn’t recorded in the database and available to other officers.

The inquest has heard that four police officers missed the opportunity to arrest Anderson two weeks before he killed Luke because of the incomplete police data system.

– with ABC, AAP