A drug dealer's "tragic choice of words" to Aleksander Vojneski as he desperately searched for ice were a catalyst for him stabbing his partner to death in her Macgregor home, prosecutors say.
The jury are currently hearing closing submissions in the murder trial of Vojneski, 31, following five weeks of evidence in the ACT Supreme Court.
Vojneski is accused of stabbing his partner, mother of three Paula Conlon, to death on the night of March 27, 2012.
But barrister Jack Pappas told the jury late on Thursday that the circumstantial case against his client was "full of holes", and that police chased the easy target after forming a theory within 12 hours of the killing.
"Some policeman's theory is not enough for you to convict someone of murder," he said.
The pair's six month relationship had been marked by instability and violence in the lead up to Ms Conlon's death, the Crown say.
Vojneski was an ice user with an alleged history of violence and knife use.
On the night of the murder, he had been at Ms Conlon's home drinking and allegedly looking for drugs on credit, because he had no money.
Ms Conlon, on the other hand, was trying to wean Vojneski off ice, believing she was pregnant.
She had sent a message to Vojneski's brother the week prior, after he congratulated her on the news.
"Thanks. Bit scary hey? I told Alex he needs to stop ice before baby arrives or he'll lose us both," she wrote.
Ms Conlon had also spent the last of her money on clothes, which arrived the morning of the murder.
Crown prosecutor Shane Drumgold said Vojneski was in a state of "increasing desperation" when he called one drug dealer at 8.47pm.
The drug dealer said Vojneski had asked if he could "'tick some stuff, some gear".
"I said 'look mate, give me an hour and I'll see how I go,'" the drug dealer told him, despite having no intention of answering further calls.
That, Mr Drumgold said, was a tragic choice of words.
"Why? Because we say it gave the accused hope," he said.
"It was the gradual crushing of this hope that provided the ingredients of this tragic night."
Vojneski, frustrated by unanswered texts and calls, began "scraping the bottom of his contact barrel", the Crown say.
Not long after, Mr Drumgold said Ms Conlon was murdered by Vojneski at 10.10pm.
A teenage boarder staying at Ms Conlon's house heard arguing, the words "no, no, no", and a loud scream.
Ms Conlon's body was found the next day, as was the receipt for her clothes, which had been torn up in the sink.
Mr Drumgold also outlined the forensic case against Vojneski, the strange lack of contact he had with Ms Conlon the next day, his behaviour immediately before and after his arrest, and the absence of any alternative theories about Ms Conlon's murder.
He also pointed to the "extensive interactions" Vojneski had with his mother Julie Vojneski and brother Vladimir Vojneski on the day after the killing.
But Mr Pappas said police had a "blinkered commitment to a theory hatched in 12 hours" during their investigation of Ms Conlon's killing.
He said DNA tests of the clothes Vojneski was found in after the murder were not done, despite a belief he had changed from what he was wearing after the alleged crime.
Mr Pappas criticised the Crown's "scattergun approach" to Vojneski's supposed motive, and said police had stopped investigating an acceleration mark found on the road outside Ms Conlon's home when they realised Vojneski didn't drive.
He warned the jury that Vojneski had the presumption of innocence, and that it was not enough for them to merely be suspicious that he might have killed Ms Conlon.
Mr Pappas also urged them to analyse the evidence, and not look at the case through the lens of prejudice or emotion.
His closing submission will continue on Friday before Justice John Burns.