Combrink interrogated Otto about specific details pertaining to the standard operating procedures (SOPs) when analysing DNA evidence.
While under cross-examination, Otto said that of the 160 staff members at the police forensic laboratory, at least 20 if not more, had been involved in handling the Van Breda case evidence, and that the SOPs they adhere to were determined by international guidelines.
Otto faced relentless questioning by Combrink, answering every one about the SOPs and at one point she said: “It’s a pity you can’t visit our offices.”
Combrink tried to discredit Otto, referring to a certificate of Otto’s training dating back to 1997, but Otto explained that the SOPs had evolved over time and that the procedures at that time were not the same as the current ones. “We cannot deviate from the SOPs,” Otto told the court, adding that she had completed her training “with flying colours”.
She pointed out that when processing the DNA, they needed 0.005 nanograms per microlitre after qualification, in order to create a DNA profile.
They cannot have anything less, as the equipment they use would not be able to create a sufficient profile for the analyst to use.
“It’s dangerous working with too little DNA and dangerous when working with too much, which is why there is a set amount,” Otto said.
Judge Siraj Desai asked Otto if she would be comfortable discussing the SOPs if Combrink had to pick out any part in the evidence that had been submitted.
“I work closely with the SOPs. Without context it is fine, but if I need to apply context, then I would ask to place something into context,” she replied.
Otto was put through examples that tested her knowledge on the stand.
Judge Desai adjourned the proceedings after a day of technical questioning from Combrink, stating that the court will proceed today to make up for the public holiday on Wednesday.
Van Breda stands accused of the murder of his older brother, Rudi, his father Martin, and his mother Teresa.
He also faces a charge of attempting to murder his sister, Marli.