A Melbourne man has admitted in the witness box that he "snapped" on the night he drowned his ex-lover in a bathtub and that it wasn't part of a pre-arranged suicide pact.
Murat Davsanoglu, 43, pleaded not guilty to murdering 34-year-old Ozlem "Ozzie" Karakoc in Dandenong in July last year, based on a claim her death was part of an agreement they'd been discussing for months beforehand.
"I just snapped that night, okay, that's it," he told the jury under cross-examination by prosecutor Diana Piekusis SC on Thursday.
Davsanoglu and Ms Karakoc had been in a relationship over an 18-year period before her death at Dandenong on July 14 last year.
He told the jury it was an open relationship and she had been seeing two other men and he was with another woman at the time.
Davsanoglu agreed he snapped at her because she was starting a new relationship with Ozden Gonullu, and he was angry at the thought of losing her.
"That's the reason you killed her," Ms Piekusis said.
"That is correct, miss, yes," he said.
Justice Lex Lasry sought clarification.
"So there was no suicide pact on that night," he asked.
"Not on that night, no," Davsanoglu replied.
Until Thursday's admission, Davsanoglu had denied murderous intent.
His lawyer John Desmond said the "tragic case" involved "two people who are in love" and saw no way out of their situation other than to kill themselves.
"He killed her, drowned her, pursuant to that agreement," Mr Desmond said previously.
In the witness box on Thursday, Davsanoglu maintained a suicide pact had existed between them in the months leading up to Ms Karakoc's death.
He said they discussed plans face to face in February and March last year, and over WhatsApp messages between April and May.
They were going to buy a gun and he would shoot her and then himself, he said.
Davsanoglu said he had deleted those messages and police were unable to retrieve any messages between the pair prior to June 5 last year.
The trial has previously heard Ms Karakoc had a major depressive disorder with psychotic episodes, but her psychologist Semra Durmaz said she had never expressed suicidal thoughts to her.
She spoke to Ms Karakoc on the phone days before her death.
"It was the first time I heard her sound so happy," she told the jury last week.
The prosecution says Davsanoglu drowned Ms Karakoc, drove the body to South Australia and returned, placing her body in a suburban garage before handing himself in to police.
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