Keith Cowell, his son Matthew and a third man were shot dead
Three men killed at a house in Hertfordshire all died from shots to the head, a court has heard.
Keith Cowell, 52, and his son Matthew, 17, had six bullet wounds and Tony Dulieu, 33, from Essex, had two, but was also stabbed and hit with "force".
Kevan Thakrar, 21, of Stevenage, and Miran Thakrar, 24, of no fixed address, deny murder at St Albans Crown Court.
Pathologist Nat Carey told the court all would have died rapidly and Dulieu was possibly hit with a gun butt.
All three were killed about 2130 BST on 28 August last year at a house in Plaw Hatch Close, Bishop's Stortford, in an underworld drug deal which had gone wrong, the prosecution claims.
Consultant forensic pathologist Mr Carey said he visited the scene the day after the killings and saw Tony Dulieu's body in front of the fireplace in the lounge.
Matthew Cowell's body was close by, in front of the sofa.
Keith Cowell was lying "awkwardly" on the kitchen floor with his head through the threshold of the doorway into the dining area of the through lounge.
The jury was shown photographs of the victims and were given a "body map" indicating the different bullet wounds and the tracks of their entry and exit points.
Toxicology tests showed Dulieu, who died from multiple brain injuries, had previously taken cocaine.
Keith Cowell had taken cocaine, cannabis and a painkiller and his cause of death was a shot to his head.
Matthew Cowell suffered a fractured skull causing brain damage and a bullet, which lodged in the spine of his neck, and partially severed the spinal cord.
He had previously taken cocaine and cannabis and died from multiple bullet wounds.
Three other men and a woman are also on trial for offences linked to the attack.
The trial continues.