A Ballarat police sergeant has told a court he punched his female neighbour, breaking her nose, because he feared what she was going to do.
Sergeant David Berry gave sworn evidence at a contested hearing at the Ballarat Magistrates Court on Friday after the prosecution closed its case.
The veteran police member has been charged with one count of unlawful assault against Ballarat woman Samantha Mitchell in the early hours of May 4, 2017.
The punch allegedly occurred in a Newington street after Ms Mitchell claimed she went to Berry's house for help because she had had an argument with her partner, who forced her out, and her children were at his house.
Berry told the court he woke to a loud bang and got out of bed immediately, put on a dressing gown and walked bare-foot out onto his porch.
He said he heard a distinctive sound coming from the meter box at the side of his house and yelled out, "who's there?".
"I had absolutely no idea what was going on," Berry told the court.
He said he then saw a figure he believed was a female run out the driveway before he started chasing this person and calling out.
Berry said the person slowed down and he took a step towards them in the darkness. He realised it was Ms Mitchell, who he had raised her arms outwards.
"I thought she was going to hit me or grab me. I had no idea what was in her hands at the time. I was fearful what was taking place and what she was going to do," Berry said.
"I punched her."
Berry told the court he was aware Ms Mitchell had been involved in violent incidents with her partner before the assault.
He said Ms Mitchell had approached him one day and asked him if he could inquire about her court case, which he did.
Defence barrister Malcolm Thomas said Ms Mitchell had a tendency to suddenly and without warning, become violent towards males.
The court was told after Berry punched Ms Mitchell and she fell to the ground, he leaned over her and asked her what her problem was and what had he done, to which she replied, "whatever Dave".
Berry then left Ms Mitchell and walked back to his house where he phoned police.
Prosecutor Matthew Cookson asked Berry if he returned to Ms Mitchell, to which he replied "no" because he did not see an injury and "certainly not" blood.
"In hindsight I probably could have asked if she was OK. I felt terrible because what I have been involved in," Berry said.
Before the punch, there had been 12 triple-0 calls relating to Ms Mitchell. One police officer, Constable James Oliver, responded to the domestic dispute in Newington.
He said Ms Mitchell was erratic, her behaviour was heightened and she was unsteady on her feet.
The prosecution will continue to cross-examination Berry on Tuesday before magistrate Frank Jones.
Have you signed up to The Courier's daily newsletter and breaking news emails? You can register below and make sure you are up to date with everything that's happening in Ballarat.