Triple murder accused Henri van Breda will hear his fate in the Western Cape High Court on Monday.
Van Breda pleaded not guilty to axing his parents and brother to death, seriously injuring his sister Marli, and defeating the ends of justice.
He alleged that an intruder, wearing a balaclava, gloves and dark clothing, was behind the attack, and that he had heard other voices of people speaking Afrikaans in the family's Stellenbosch home in January 2015.
Van Breda claimed that, after a fight with the axe-wielding intruder who was also armed with a knife, the man had fled their home situated in the centre of the lavish De Zalze Golf Estate.
Defence advocate Pieter Botha, in closing arguments, insisted that the totality of the evidence against his client did not exclude the possibility of an unknown assailant.
He said the State had not produced evidence which proved beyond a reasonable doubt that there were no unidentified attackers in the Van Breda home that day.
Prosecutor Susan Galloway argued that there was no motive for someone, such as a hitman, to go to the Van Breda family's home and commit the crime.
She argued that circumstantial evidence pointed to the Van Breda couple's middle child being the attacker and that his injuries were self-inflicted, or inflicted by his family members during the attack.
The attack would also have been premeditated, as Van Breda would have had to arm himself before making his way to the second floor of the house to execute the murders.