The absence of Marli Van Breda's blood on the axe used to hack her parents and brother to death appeared to revive the defence's argument that two different axes may have been used in the De Zalze triple murders, the Western Cape High Court heard on Wednesday.
Advocate Pieter Botha, for Henri Van Breda, further questioned why the teenager's blood was not on the shorts and socks her murder-accused brother had been wearing at the time of the gruesome attacks.
Botha, during cross examination of blood spatter analysis expert Captain Marius Joubert, referred back to his client's plea explanation in which he said he had heard more than one person in their house. He argued that if Marli was attacked with another similar object, it would explain the blood absence from the axe.
Joubert countered that Marli sustained separate lacerations spread out over the head and neck, which wouldn't necessarily immediately bleed after being sustained. He explained that different areas were struck, making the possibility of blood transfer minimal as the attacker created new wounds every time.
He conceded that one would expect to find her blood on it.
"But the absence of evidence is not evidence of absence," Joubert said.
Botha referred to photos of Marli in hospital, which he says show that injuries were quite close together.
According to the neurosurgeon who treated her, she had suffered five deep lacerations to her skull, one on her wrist and one to the neck.
Joubert said the spatter from the attack on Marli would go away and not toward the attacker as his position and other variables may influence this.
Pathologist Dr Daphne Anthony during her testimony had said the then 16-year-old appeared to have had a more severe altercation with the attacker and had fought back, leading to Botha asking why her blood had then not transferred onto his client's clothes.
The defence's advocate Matthys Combrink earlier in the trial pointed out that only the family's domestic worker, Precious Munyongani said she recognised the axe used in the gruesome attack as the one she had seen stored on a shelf in the scullery of 12 Goske Street.
Marli's ex-boyfriend James Reade-Jahn during his testimony remembered a black axe being used in the house.
Judge Siraj Desai at the time appeared incredulous at the notion of another axe.
Van Breda, 22, pleaded not guilty to the murder of his parents and brother, attempted murder of Marli and defeating the ends of justice.
He claimed that an intruder wearing a balaclava, gloves and dark clothes was behind the attack, and that he had heard other voices of people speaking Afrikaans in their home in the De Zalze Estate in Stellenbosch in January 2015.
Van Breda claimed that, after a fight with the axe-wielding intruder, the man had escaped.
The trial resumes on Thursday.