The case against a Canberra man accused of murdering his girlfriend is based on a "flimsy hypothesis of guilt", a jury has been told.
Aleksander Vojneski, 31, is accused of killing 30-year-old Paula Conlon in her Macgregor home on the evening of March 27, 2012.
The ACT Supreme Court heard Conlon died after a frenzied stabbing attack during which the knife went through her arm and a chest wound caused catastrophic internal injuries.
Both the prosecution and defence have finished giving evidence after more than a month of hearings, and the jury is expected to retire to consider its verdict on Monday.
During the trial, prosecutor Shane Drumgold outlined a circumstantial case against Vojneski.
However, defence lawyer Jack Pappas said the crown had used selective evidence and taken a quantum leap to suggest that when Vojneski could not get drugs he went about stabbing people.
"When you start to look at this hypothesis it starts to look flimsy, and that's the hypothesis of guilt," he said.
Mr Drumgold that said on the night of Conlon's death, Vojneski became aggressive and violent and that his behaviour was fuelled by alcohol, drugs and frustration at being unable to buy drugs on credit.
In an unusual move, the prosecution was allowed to present evidence to the jury which outlined Vojneski's previous involvement in violent incidents, including when he attacked his sister's boyfriend with a knife.
The court heard evidence from Vojneski's mother and brother that when he was becoming out of control, he would annoy the neighbours by being loud and throwing things around.
Mr Pappas told the court the police had been too quick to focus on his client and to reject any evidence that someone else may have been involved.
Mr Pappas also questioned whether the estimated time of Conlon's death was accurate.No knife, no definitive evidence linked Vojneski: defence
The jury has heard that no knife has been found and no definitive forensic evidence linked Vojneski to Conlon's death.
In summing up to the jury, Mr Drumgold said he had a strong circumstantial case against Vojneski and there was evidence from Conlon's friends about violence between the pair.
But Mr Pappas said there were substantial pieces missing from the forensic evidence.
"How do you commit a crime like this and leave no forensic evidence not only on your clothes, not only on your body, not only on the body of the deceased," he said.
Small amounts of Vojneski's blood were found on the door handle of the bedroom and the hallway floor.
The prosecution told the court Vojneski had cut his index finger during the attack on Conlon, and that is where the droplets of blood had come from.
But Mr Pappas said that was not plausible and the cut could have happened when Vojneski was cutting fruit in the kitchen.
Conlon's body was not found until the afternoon after her death, despite the fact her young boarder was at home playing games online in his room.
Mr Pappas reminded the jury the boy had said the pair were happy on the evening of hear death and were getting along.
The boy gave evidence he heard a scream and Conlon said "no" several times, but he did not go out of the room until much later because he was scared.
The court heard the boy had gone off to school the next day without realising Conlon lay dead in her bedroom.
During the trial, the jury was told how Vojneski and Conlon had been in a stormy six-month relationship.
The two met at a mental health facility where Conlon was receiving treatment for depression after the break-up of her marriage.
Justice John Burns will address the jury on Monday before it retires to consider its verdict.