Prosecutor Candy Kander argued that acting Judge Louis Barnard should convict Jabulani Ngobese, 28, of the murder of Micky Hampson, 68, and the attempted murder of his son Murray Hampson, 34, of Eston.
She said he had associated himself with the actual killer, Sibuniso Mtolo, 26.
Mtolo, who pleaded guilty to the crimes, was jailed for life by Judge Isaac Madondo on 14 March, but co-accused Ngobese pleaded not guilty to the charges of aggravated robbery, murder and attempted murder.
Evidence was given that in last September, Ngobese and Mtolo of the Amanzimtoti area had walked to the Hampsons' farm in daylight to steal a vehicle, even though workers and the Hampsons saw them walking on their farm.
The Hampsons asked what they were doing on the farm and made them get onto their bakkie because there had been a burglary on a neighbour's farm.
They intended to hand them to the police to make investigations.
Murray Hampson, armed with a shotgun, sat in the bin of the bakkie with the intruders.
After a fracas the gun was taken from Murray and Mtolo pointed it at Murray who was on the ground.
Murray said he saw Mtolo's finger squeezing the trigger but was saved because the safety catch was on.
Murray said during the struggle Ngobese tried to stab him but the knife blade passed between his side and his arm.
Kander said Ngobese helped Mtolo to get hold of the shotgun.
Mtolo pursued Micky Hampson who was driving away and shot him at point-blank range. He died sitting at the steering wheel.
Murray ran into the sugar-cane as he thought that Mtolo would also shoot him.
Ngobese's defence counsel Mahen Rajcumar asked Barnard to apply caution in his judgment.
He said that what started as an amateurish attempt to steal set off a chain of events not sufficient to link Ngobese to the murder, attempted murder and robbery.
Barnard would give judgment on Thursday.