"Porsche is prone to aquaplane. Porsche acknowledged the defect. They had to tell drivers that there was this defect and take measures to fix it."
However, prosecutor Yusuf Baba said Zuma had a case to answer. He argued that the onus was on the driver to act responsibly on the road. "Drivers must always be aware that they are in control of an instrument that can take life.
"Any car can aquaplane, the point is what actions you took prior. It does not remove the duty of the driver," said Baba.
Earlier in the day, accident investigator Johan van Loggerenberg said he concluded during the investigation that the crash may have been caused by human error. But he said he could not rule out the fact that aquaplane could have caused the crash.
One of the crash survivors, Charlotte Ndlangisa, relived the day she lost her friend Dube in the crash. She said she was sitting next to Dube in the taxi when it was hit by Zuma's Porsche.
"[After the crash] she was hanging on the window, her hair and eyes were full of blood. I realised that she was dead when she did not respond when I called her name," said Ndlangisa.
Ndlangisa said after the crash Zuma helped her into his luxury car to shield her from the rain.
Zuma Snr, who attended part of the proceedings, said it was difficult to tell if his son's prosecution was a way of getting back at him. Duduzane's twin sister, Duduzile, was also in court. The case was postponed to tomorrow for judgment.