Cape Town - The blood on Henri van Breda's grey pyjama pants, T-shirt and elsewhere in the luxury De Zalze home could help solve the mystery surrounding the axe murders of the Van Breda family in the coming weeks.
The murder case against Henri resumes in the Western Cape High Court in Cape Town on Monday with the State's forensic testimony.
Witnesses' memories sometimes are unreliable, but blood doesn't lie, two forensic experts told Netwerk24 last week.
The State's forensic evidence includes the long grey pyjama pants which Henri said in his statement he'd worn on the night his father, Martin, mother Teresa and brother Rudi were hacked to death with an axe. The police had kept the pants because they seemingly had blood on them.
The evidence included black women's panties which possibly also had blood on them.
The independent experts Netwerk24 spoke to said the State and Henri's version of what happened would depend on the testimony of blood spatter experts particularly.
Captain Marius Joubert of the police's forensic laboratory in Cape Town, who also testified in the Oscar Pistorius murder trial, will probably be called to testify.
Wes van der Westhuizen of Wesco Forensic Services in Pretoria, who helped analyse the blood spatter patterns in the Pistorius case, said: "Blood spatter patterns and DNA will find the accused in the axe murders guilty or acquit him.
"The victims all had head wounds, so there was a lot of blood. The attacker would obviously also have been full of blood and if he had walked around in the house, there would have been blood dripping from the murder weapon."
It is probably possible to determine where the attacker had stood, how the blood had got on the grey pants and where blood might possibly have been washed off in the house, Van der Westhuizen said.
According to the State's list of evidence a mop and nine dishcloths were analysed, although there hadn't been obvious blood stains on them.
There was, however, blood in the corner of the shower and on a towel, State witness Warrant Officer Lorraine Nel said in a statement.
The State alleges that Henri tampered with the scene after murdering his family.
Another independent expert who, for professional reasons didn't want to be identified, said if there was DNA from Henri's sister Marli, who survived the attack, on the clothes the accused was wearing that night, it would raise many questions.
"Nowhere in his statement did the accused say that he tried to help the victims or that he touched them."
Henri claims he was in the bathroom when the assailant first attacked Rudi, then his father and then the two women. He and the attacker wrestled and he seized the axe, Henri said.
The experts say Henri's explanations can in all probability be tested with the forensic evidence, as was the case in other high profile cases.
In the Griekwastad murder case, Don Steenkamp alleged that his clothes had blood on because he was holding his dying sister. However, it was expert police testimony which convinced Judge Frans Kgomo that it couldn't be possible.
The patterns in which the blood had been transferred did not correspond with Steenkamp's account, the court found.
In the Inge Lotz case, it was expert testimony on a shoe print in blood that scuppered the State's case.
Because of the essential importance of this kind of testimony, it is common for the defence to appoint their own forensic experts.
Henri has acquired the services of Dr Reggie Perumal, a pathologist, Cobus Steyl, a ballistics expert who can testify about the projection of the axe which allegedly was thrown, and Dr Mike du Trevou, a neurosurgeon who can testify about Henri's injuries which apparently left him unconscious.