Ashleigh Wallace, 27, her brother Shaun, 19, and Patrick Herbert, 37, took 49-year-old Stephen Grant’s life in July 2018.
On Thursday, the High Court in Edinburgh heard how the trio killed Stephen at a flat in the city’s Magdalene Drive.
The trio stabbed Stephen 10 times - inflicting wounds on his head, body and legs - before repeatedly striking him with “objects” which remain unknown to police.
And neighbours heard Ashleigh shout ‘kill him, kill him, kill him” during the attack.
Herbert and Shaun Wallace removed Mr Grant from the flat and then dumped him outside on a back green for him to die.
Herbert, whose picture can not be revealed for legal reasons, then obtained his victim’s mobile phone and used it to take a series of selfie photographs of himself. He then went to sell Valium to drug users in Edinburgh city centre.
But the trio were later arrested after police found DNA evidence which linked them to the crime scene. They also discovered Mr Grant’s blood on clothing and shoes belonging to the accused.
Detective Inspector Bruce Coutts, from Corstorphine CID, said: “Mr Grant was subjected to a horrifically violent and sustained attack which cost him his life.
“He was left for dead in the back garden by Ashleigh Wallace, her brother Shaun Wallace, and Patrick Herbert, who showed complete disregard for Stephen’s life and have shown no remorse for their actions.”
On Wednesday, during the 14th day of proceedings, jurors found the three accused guilty of murder.
Judge Lady Carmichael remanded them in custody and deferred sentence for the court to obtain reports on their characters.
She said: “The sentence for this offence will inevitably be life imprisonment. I’m adjourning this sentence and ordering social enquiry reports. You will be sentenced at a future diets.”
Sentencing is due to take place on April 25th.
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