Caroline Igoe was also accused of an "act of breathtaking hypocrisy" by gathering with the distraught family of Martyn Barclay as he lay dying in hospital.
The claims were made as the prosecution summed up its case against Igoe, 32, and her brother, Paul, at the High Court in Edinburgh.
Caroline and Paul Igoe are both accused of the murder of Mr Barclay, who was shot in the head in the Inch's Hazelwood Grove in January last year.
In his address to the jury, advocate depute Alex Prentice QC said: "In regard to the charge of murder, the Crown seeks a guilty verdict on Caroline Igoe on the basis that she pulled the trigger, and on Paul Igoe on the basis that he was an active participant in the shooting."
Mr Prentice also dismissed suggestions that Mr Barclay had committed suicide, or had been the victim of a gangland hit.
Earlier in the day, Caroline Igoe had taken to the witness stand and denied having any role in Mr Barclay's death, telling the court she found him lying in a pool of blood.
She admitted that her brother had picked up a handgun from the ground next to Mr Barclay before taking it from the scene.
She told the court that she had spoken to her brother on the phone before finding her boyfriend injured, and saw him coming down the street from his home in nearby Walter Scott Avenue as she stood near the body.
Asked how she felt at the time, Igoe said: "I was frightened, didn't know what to do. I went out and tried to get Martyn up.
"I couldn't get him up, he was breathing quite heavily and had a gurgling noise coming from him."
Ms Igoe told the court that she knew Mr Barclay possessed a gun, and gave him something she believed was a dish towel to wrap it in in the days before his death.
Ms Igoe admitted telling police that a pillowcase and socks found in the street after the shooting, which forensic tests showed contained both firearms residue and her DNA, did not belong to her. She now accepted that the items had been used to "wrap" the gun and that they came from her home.
She denied knowing where the gun was kept, telling the court that she thought her boyfriend had buried it after she told him not to bring it to her parent's Hazelwood Grove home where the couple were staying.
She said that Mr Barclay had been out with his friends in the hours before the shooting and was "really drunk", and the pair had rowed over the phone during a number of calls.
Her defence advocate Jim Keegan QC asked her how she came to know Mr Barclay was lying outside.
She said: "I heard somebody shouting 'Caroline'. I ignored it. Then I thought I heard a stone getting thrown at a window.
"I looked out the window and saw Martyn lying on the ground and I thought he was drunk ."
Under cross examination, Mr Prentice said to Ms Igoe: "The truth is that you shot Martyn Barclay?"
She replied: "No I did not."
Mr Prentice said: "You then associated yourself with members of the Barclay family in an act of breathtaking hypocrisy?"
Ms Igoe said: "No I did not."
In his closing speech to the jury, Mr Prentice told the jury: "I suggest to you that was an act of cold-blooded murder executed with a chilling military precision and the answer to who was responsible for that is found in the dock at the High Court in Edinburgh."
Both Caroline and Paul Igoe deny murdering Mr Barclay and firearm charges, involving possession of a gun and attempting to pervert the course of justice.
The trial continues.